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Bir sunucumda Postfix MTA kullanıyorum. Bu aralar oldukça fazla spam e-posta gelmeye başladı.

Gerekli olan paketi kuralım.

sudo apt-get install postfix-policyd-spf-python

yapılandırma dosyamızı düzenleyelim.

cd /etc/postfix-policyd-spf-python

~# nano policyd-spf.conf

dosya içeriğin  temizleyip aşağıdaki içeriği yapıştırın.

debugLevel = 1
TestOnly = 1
HELO_reject = Fail

Mail_From_reject = Softfail

PermError_reject = False

TempError_Defer = False

skip_addresses = 127.0.0.0/8,::ffff:127.0.0.0/104,::1

Hide_Receiver = Yes

Authserv_Id = HEADER
içeriği kaydedip kapatın.

 

~# nano /etc/postfix/master.cf


#------------- SPF ---------------------------------------------------
policy-spf  unix  -       n       n       -       -       spawn
     user=policyd-spf argv=/usr/bin/policyd-spf
#------------- SPF ---------------------------------------------------

 

En alta satıra inip ekleyip kaydedin.

 

~# nano /etc/postfix/main.cf

#------------- SPF --------------------
policy-spf_time_limit = 3600s

smtpd_recipient_restrictions = permit_sasl_authenticated,permit_mynetworks,reject_unauth_destination,check_policy_service unix:private/policy-spf
#------------- SPF --------------------

~# service postfix restart


Sonuç

root@battalgazi:~# grep www.openspf.net /var/log/mail.log
Jun 24 01:03:49 battalgazi policyd-spf[10618]: 550 5.7.23 Message rejected due to: SPF fail - not authorized. Please see http://www.openspf.net/Why?s=helo;id=microsoft.com;ip=94.102.15.233;r=<UNKNOWN>
Jun 24 01:03:49 battalgazi postfix/smtpd[10552]: NOQUEUE: reject: RCPT from server.wegagroup.com[94.102.15.233]: 550 5.7.23 <caylak@truvalinux.org.tr>: Recipient address rejected: Message rejected due to: SPF fail - not authorized. Please see http://www.openspf.net/Why?s=helo;id=microsoft.com;ip=94.102.15.233;r=<UNKNOWN>; from=<gates@microsoft.com> to=<caylak@truvalinux.org.tr> proto=SMTP helo=<microsoft.com>
Jun 24 01:13:57 battalgazi policyd-spf[12010]: 550 5.7.23 Message rejected due to: domain owner discourages use of this host. Please see http://www.openspf.net/Why?s=mfrom;id=gates@gmail.com;ip=94.102.15.233;r=<UNKNOWN>
Jun 24 01:13:58 battalgazi postfix/smtpd[11837]: NOQUEUE: reject: RCPT from server.wegagroup.com[94.102.15.233]: 550 5.7.23 <caylak@truvalinux.org.tr>: Recipient address rejected: Message rejected due to: domain owner discourages use of this host. Please see http://www.openspf.net/Why?s=mfrom;id=gates@gmail.com;ip=94.102.15.233;r=<UNKNOWN>; from=<gates@gmail.com> to=<caylak@truvalinux.org.tr> proto=SMTP helo=<smtp.gmail.com>
Jun 24 01:17:30 battalgazi policyd-spf[12674]: 550 5.7.23 Message rejected due to: domain owner discourages use of this host. Please see http://www.openspf.net/Why?s=mfrom;id=finansmerkezi03@aol.com;ip=94.102.15.233;r=<UNKNOWN>
Jun 24 01:17:30 battalgazi postfix/smtpd[12599]: NOQUEUE: reject: RCPT from server.wegagroup.com[94.102.15.233]: 550 5.7.23 <caylak@truvalinux.org.tr>: Recipient address rejected: Message rejected due to: domain owner discourages use of this host. Please see http://www.openspf.net/Why?s=mfrom;id=finansmerkezi03@aol.com;ip=94.102.15.233;r=<UNKNOWN>; from=<finansmerkezi03@aol.com> to=<caylak@truvalinux.org.tr> proto=SMTP helo=<smtp.aol.com>
root@battalgazi:~# 

 Başarılı :)

Perl versiyonu için 

http://www.serdarkok.com/linux/postfix-spf-entegrasyonu


 


 

WebP yeni bir format olduğu için olmalı ki Linux altında bile çalışmak bazen çok zor olabiliyor.

Daha da darlayan ise bu formatı nautilus üstünde küçük resim olarak gösterebilmek. Çok takla attım, lakin neyi nerede çözdüğümü de unuttum. Şimdi sırf bu yazıyı yazabilmek için tüm WebP desteğini kaldırıp, yeniden başlıyorum. Kıymetini bilin.

Baştan belirtelim, resim formatı olduğu için doğal olarak GIMP bu formatı da destekliyor ve açabiliyor, değiştirebiliyor, kaydedebiliyor. Lakin 300 resmi tek tek GIMP ile açıp kontrol etmek çok saçma bir çaba. Hem de bunu küçük resim (thumbnail) ortada yokken yapmak çok daha zor. 

İlk önce GNOME/Ubuntu ortamındaki sorunu çözelim. Korktuğunuz kadar zor değil, sadece bir PPA ekliyoruz ve küçük bir kurulum yapıyoruz. Tedbir amaçlı en son dosyalar uygulamasını yani nautilus’u kapatıyoruz.


sudo add-apt-repository ppa:krifa75/eog-ordissimo
sudo apt update && sudo apt install webp-pixbuf-loader

 

 


Yazının devamı için tıklayınız.

 

Kaynak: http://www.yakusha.net/ubuntu-20-04-icin-webp-destegi-eklemek/

 

[full-post]

 



How to Install a Mail Server with PostfixAdmin on Ubuntu 20.04

 

In this tutorial, we’ll be covering the process of setting up a mail server with Postfix, Dovecot, Postfixadmin and MariaDB on an Ubuntu 20.04 VPS. But first, what is PostfixAdmin?

PostfixAdmin is an open-source web-based application written in PHP that’s used to create virtual domains and email accounts for a Postfix mail server. Using PostfixAdmin, we can manage mailboxes & aliases, set quotas, configure vacation/out-of-the-office messages, and more. Plus, the web-based interface gives you the user-friendliness of a browser window with a UI.

PostfixAdmin allows us to use virtual email addresses and virtual mailboxes, so we do not need to create a new system user account for each email address. Considering all of these details, PostfixAdmin is a versatile tool and can be used for almost all of your mailing needs. This tutorial goes quite in-depth and may take some time to configure everything properly. Let’s get started with the installation steps.


Hardware/Software Requirements

  • An Ubuntu 20.04 server or VPS with root access enabled, or a user with sudo privileges. We provide all of our users will full root access on their VPSes.
  • Postfix mail transfer agent (MTA) and Dovecot IMAP/POP3 Mail Delivery Agent need to be installed.
  • A database server (MySQL/MariaDB, PostgreSQL or SQLite) needs to be installed.
  • Apache web server needs to be installed with the mod_rewrite module enabled.
  • PHP 7.1 or greater must be installed with the imap, mbstring and mysql extensions all enabled.

Step 1. Getting Started

To begin, we’re going to need to log into our server using SSH. You can do that by entering this command:

ssh root@IP_Address -p Port_Number

Remember to replace “root” with your username if you are not using the root user. Change the values in red according to your server’s IP address and SSH port number (the default number is 22, so try that first unless your server uses a custom port number).

Once you are logged in, you should update all of your packages to their latest available versions.

apt-get update -y
apt-get upgrade -y

Once all the packages are up-to-date, restart your server to apply the configuration changes and ensure that all software is running on their latest versions.

Step 2. Create a System User Account

PostfixAdmin has the ability to create multiple virtual domains, users and aliases. This saves us the hassle of having to create new system users whenever we need a new email account added. For security reasons, we will create a new user named ‘vmail’ with permissions to store the emails in the /var/vmail directory:

useradd -r -u 150 -g mail -d /var/vmail -s /sbin/nologin -c "Virtual Mail User" vmail
mkdir -p /var/vmail
chmod -R 770 /var/vmail
chown -R vmail:mail /var/vmail

Step 3. Install PHP, Apache and Required Extensions

PHP 7.4 and Apache2 are included in the default Ubuntu repository for 20.04. We can install Apache 2, PHP 7.4 and the required PHP extensions using the following command. We also included the required PHP and Apache modules in the command:

apt-get install apache libapache2-mod-php php php-common php-mbstring php-imap php-mysql

Step 4. Install MariaDB Server

PostfixAdmin requires a database in order to be able to store the email account and domain information. For the purpose of this tutorial, we will use a MariaDB database system, an open-source version of MySQL that maintains feature parity. We can install the MariaDB server using the following command:

apt-get install mariadb-server mariadb-client mariadb-common

Start the MariaDB service and enable it to start on server boot using the following commands:

systemctl start mariadb 
systemctl enable mariadb

In order to improve the security of your MariaDB installation, run the mysql_secure_installation script:

mysql_secure_installation

When prompted, you can set the MariaDB root password and safely answer ‘Y’ to all questions.

Enter current password for root (enter for none): Just press the [Enter] key since there is no default password
Set root password? [Y/n]: Y
New password: Enter a strong password
Re-enter new password: Repeat the same password from before
Remove anonymous users? [Y/n]: Y
Disallow root login remotely? [Y/n]: Y
Remove test database and access to it? [Y/n]: Y
Reload privilege tables now? [Y/n]: Y

If you followed the above steps, then you will have a password set for the MariaDB root user.

Run this command to access the MySQL console:

mysql -u root -p

And enter the root password you set previously using the mysql_secure_installation script. If you chose not to run that script, there is no password set, so you just need to press the [Enter] key once.

Next, create a MariaDB user and database for PostfixAdmin:

MariaDB [(none)]> CREATE USER 'postfixadmin'@'localhost' IDENTIFIED BY 'Strong_Password';
MariaDB [(none)]> CREATE DATABASE postfixadmin;
MariaDB [(none)]> GRANT ALL PRIVILEGES ON postfixadmin.* TO 'postfixadmin'@'localhost';
MariaDB [(none)]> FLUSH PRIVILEGES;
MariaDB [(none)]> \q

Do not forget to replace ‘Strong_Password‘ with a good and unique password.

Step 5. Install Postfix

Install Postfix and postfix-mysql packages by running the command below:

apt-get install postfix postfix-mysql

During the Postfix installation, you will be asked for the type of mail configuration. Select ‘Internet Site’ and click on OK to continue. Then, enter the server’s hostname in the ‘system mail name’ field.

Once the Postfix installation is complete, we have to create several Postfix configuration files. This will take a while as there are quite a few files that have to be made and configured.

mkdir -p /etc/postfix/sql/

Define the database connection settings for querying the virtual alias domain catchall maps by creating this file. We’re using vi, but you can use any text editor that you prefer:

vi /etc/postfix/sql/mysql_virtual_alias_domain_catchall_maps.cf

Once the file is created, insert these contents:

user = postfixadmin
password = Strong_Password
hosts = localhost
dbname = postfixadmin
query = SELECT goto FROM alias,alias_domain WHERE alias_domain.alias_domain = '%d' and alias.address = CONCAT('@', alias_domain.target_domain) AND alias.active = 1 AND alias_domain.active='1'

Create this file so we can set the database connection settings for querying the virtual alias domain mailbox maps:

vi /etc/postfix/sql/mysql_virtual_alias_domain_mailbox_maps.cf

Then insert these contents:

user = postfixadmin
password = Strong_Password
hosts = localhost
dbname = postfixadmin
query = SELECT maildir FROM mailbox,alias_domain WHERE alias_domain.alias_domain = '%d' and mailbox.username = CONCAT('%u', '@', alias_domain.target_domain) AND mailbox.active = 1 AND alias_domain.active='1'

After that, define the database connection settings for querying the virtual alias domain maps by creating this file:

vi /etc/postfix/sql/mysql_virtual_alias_domain_maps.cf

Add the following:

user = postfixadmin
password = Strong_Password
hosts = localhost
dbname = postfixadmin
query = SELECT goto FROM alias,alias_domain WHERE alias_domain.alias_domain = '%d' and alias.address = CONCAT('%u', '@', alias_domain.target_domain) AND alias.active = 1 AND alias_domain.active='1'

The next settings are for the database connection settings for querying the virtual alias maps. Create this file:

vi /etc/postfix/sql/mysql_virtual_alias_maps.cf

Add this text:

user = postfixadmin
password = Strong_Password
hosts = localhost
dbname = postfixadmin
query = SELECT goto FROM alias WHERE address='%s' AND active = '1'

There are a few more to go. Now, create a file for the database connection settings for querying the virtual domain maps:

vi /etc/postfix/sql/mysql_virtual_domains_maps.cf

Make sure you set the passwords on all of these files that you have been adding. Add the contents:

user = postfixadmin
password = Strong_Password
hosts = localhost
dbname = postfixadmin
query = SELECT domain FROM domain WHERE domain='%s' AND active = '1'

Onto the next file. Create it and add the database connection settings for querying the virtual mailbox limit maps:

vi /etc/postfix/sql/mysql_virtual_mailbox_limit_maps.cf

Insert this and change the password:

user = postfixadmin
password = Strong_Password
hosts = localhost
dbname = postfixadmin
query = SELECT quota FROM mailbox WHERE username='%s' AND active = '1'

Finally, create this file and add the database connection settings for querying the virtual mailbox maps:

vi /etc/postfix/sql/mysql_virtual_mailbox_maps.cf
user = postfixadmin
password = Strong_Password
hosts = localhost
dbname = postfixadmin
query = SELECT maildir FROM mailbox WHERE username='%s' AND active = '1'

NOTE: Do not forget to replace ‘Strong_Password‘ with your own password in all of the configuration files above.

Modify the main.cf Postfix configuration file, which is the core of the Postfix configuration. Run these commands to edit each setting:

postconf -e "myhostname = $(hostname -f)"
postconf -e "virtual_mailbox_domains = proxy:mysql:/etc/postfix/sql/mysql_virtual_domains_maps.cf"
postconf -e "virtual_alias_maps = proxy:mysql:/etc/postfix/sql/mysql_virtual_alias_maps.cf, proxy:mysql:/etc/postfix/sql/mysql_virtual_alias_domain_maps.cf, proxy:mysql:/etc/postfix/sql/mysql_virtual_alias_domain_catchall_maps.cf"
postconf -e "virtual_mailbox_maps = proxy:mysql:/etc/postfix/sql/mysql_virtual_mailbox_maps.cf, proxy:mysql:/etc/postfix/sql/mysql_virtual_alias_domain_mailbox_maps.cf"
postconf -e "smtpd_tls_cert_file = /etc/ssl/certs/ssl-cert-snakeoil.pem"
postconf -e "smtpd_tls_key_file = /etc/ssl/private/ssl-cert-snakeoil.key"
postconf -e "smtpd_use_tls = yes"
postconf -e "smtpd_tls_auth_only = yes"
postconf -e "smtpd_sasl_type = dovecot"
postconf -e "smtpd_sasl_path = private/auth"
postconf -e "smtpd_sasl_auth_enable = yes"
postconf -e "smtpd_recipient_restrictions = permit_sasl_authenticated, permit_mynetworks, reject_unauth_destination"
postconf -e "mydestination = localhost"
postconf -e "mynetworks = 127.0.0.0/8"
postconf -e "inet_protocols = ipv4"
postconf -e "inet_interfaces = all"
postconf -e "virtual_transport = lmtp:unix:private/dovecot-lmtp"

We can also install Certbot, then install a new Let’s encrypt SSL certificate for the server hostname and replace /etc/ssl/certs/ssl-cert-snakeoil.pem and /etc/ssl/private/ssl-cert-snakeoil.key with the newly created SSL certificate and public key files.

Then, edit the the master.cf Postfix configuration file, and modify it as follows:

vi /etc/postfix/master.cf

Add or change the contents so that the file looks like this:

smtp inet n - y - - smtpd
#smtp inet n - y - 1 postscreen
#smtpd pass - - y - - smtpd
#dnsblog unix - - y - 0 dnsblog
#tlsproxy unix - - y - 0 tlsproxy
submission inet n - y - - smtpd
-o syslog_name=postfix/submission
-o smtpd_tls_security_level=encrypt
-o smtpd_sasl_auth_enable=yes
# -o smtpd_reject_unlisted_recipient=no
# -o smtpd_client_restrictions=$mua_client_restrictions
# -o smtpd_helo_restrictions=$mua_helo_restrictions
# -o smtpd_sender_restrictions=$mua_sender_restrictions
# -o smtpd_recipient_restrictions=
# -o smtpd_relay_restrictions=permit_sasl_authenticated,reject
-o smtpd_client_restrictions=permit_sasl_authenticated,reject
-o milter_macro_daemon_name=ORIGINATING
smtps inet n - y - - smtpd
-o syslog_name=postfix/smtps
# -o smtpd_tls_wrappermode=yes
-o smtpd_sasl_auth_enable=yes
# -o smtpd_reject_unlisted_recipient=no
-o smtpd_client_restrictions=permit_sasl_authenticated,reject
# -o smtpd_client_restrictions=$mua_client_restrictions
# -o smtpd_helo_restrictions=$mua_helo_restrictions
# -o smtpd_sender_restrictions=$mua_sender_restrictions
# -o smtpd_recipient_restrictions=
# -o smtpd_relay_restrictions=permit_sasl_authenticated,reject
-o milter_macro_daemon_name=ORIGINATING

Enable the Postfix service to start on server boot and restart the Postfix service:

systemctl enable postfix
systemctl restart postfix

Postfix is finally installed and configured.

Step 6. Install Dovecot

Dovecot is a Mail Delivery Agent which allows a user to receive emails in complete security through IMAP and/or POP3 protocols. We can install Dovecot and the dovecot-mysql package using the command below:

apt-get install dovecot-core dovecot-lmtpd dovecot-imapd dovecot-pop3d dovecot-mysql

Edit the /etc/dovecot/conf.d/10-mail.conf file:

vi /etc/dovecot/conf.d/10-mail.conf

Insert this as the content:

mail_location = maildir:/var/vmail/%d/%n
mail_privileged_group = mail
mail_uid = vmail
mail_gid = mail
first_valid_uid = 150
last_valid_uid = 150

Open the /etc/dovecot/conf.d/10-auth.conf file:

vi /etc/dovecot/conf.d/10-auth.conf

Edit it so that the file looks like this:

auth_mechanisms = plain login
#!include auth-system.conf.ext
!include auth-sql.conf.ext

Then edit the dovecot-sql.conf.ext file, and add these lines:

vi /etc/dovecot/dovecot-sql.conf.ext
driver = mysql
connect = host=localhost dbname=postfixadmin user=postfixadmin password=Strong_Password
default_pass_scheme = MD5-CRYPT
password_query = SELECT username as user, password, '/var/vmail/%d/%n' as userdb_home, 'maildir:/var/vmail/%d/%n' as userdb_mail, 150 as userdb_uid, 8 as userdb_gid FROM mailbox WHERE username = '%u' AND active = '1'
user_query = SELECT '/var/vmail/%d/%u' as home, 'maildir:/var/vmail/%d/%u' as mail, 150 AS uid, 8 AS gid, concat('dirsize:storage=', quota) AS quota FROM mailbox WHERE username = '%u' AND active = '1'

Do not forget to replace Strong_Password with the actual password that you set previously in Step 4 when creating the MariaDB user.

Edit the /etc/dovecot/conf.d/10-ssl.conf file, and enable SSL support:

vi /etc/dovecot/conf.d/10-ssl.conf
ssl = yes

Save and close that file, then edit the /etc/dovecot/conf.d/15-lda.conf file and set the postmaster_address email address.

vi /etc/dovecot/conf.d/15-lda.conf
postmaster_address = postmaster@yourdomain.com

Make sure that you change yourdomain.com to the actual domain name that points to your server.

Edit the /etc/dovecot/conf.d/10-master.conf file, find the service lmtp section and replace it with the following lines:

vi /etc/dovecot/conf.d/10-master.conf
service lmtp {
     unix_listener /var/spool/postfix/private/dovecot-lmtp {
     mode = 0600
     user = postfix
     group = postfix
     }
}

Once that part is edited, find the service auth section and replace it with the following snippet:

service auth {
     unix_listener /var/spool/postfix/private/auth {
     mode = 0666
     user = postfix
     group = postfix
}

unix_listener auth-userdb {
     mode = 0600
     user = vmail

}
user = dovecot
}

Then change the service auth-worker section to the following:

service auth-worker {
user = vmail
}

Save and close the file.

Set the correct permissions of the Dovecot configuration files:

chown -R vmail:dovecot /etc/dovecot 
chmod -R o-rwx /etc/dovecot

Enable the Dovecot service to start on server boot, and restart Dovecot so that all of these new configuration files are in effect:

systemctl enable dovecot
systemctl restart dovecot

Step 7. Install PostfixAdmin

Now that all of our required software is installed and configured, let’s install and configure PostfixAdmin and finish this tutorial.

Download the latest available version of PostfixAdmin from Github and extract it in the /var/www/html/postfixadmin directory.

apt-get install git
cd  /var/www/html/
git clone https://github.com/postfixadmin/postfixadmin.git

Edit the /var/www/html/postfixadmin/config.local.php file and add these lines:

vi /var/www/html/postfixadmin/config.local.php
<?php
$CONF['database_type'] = 'mysqli';
$CONF['database_host'] = 'localhost';
$CONF['database_user'] = 'postfixadmin';
$CONF['database_password'] = 'Strong_Password';
$CONF['database_name'] = 'postfixadmin';
$CONF['configured'] = true;
$CONF['encrypt'] = 'md5crypt';
?>

Replace Strong_Password with the MariaDB user password.

mkdir /var/www/html/postfixadmin/templates_c

chown -R www-data: /var/www/html/postfixadmin

Open http://your_server_IP/postfixadmin/public/setup.php . Check if everything is okay and make sure that there are no errors:

Scroll down and enter your new setup password twice. Make sure to choose a strong one:

Then click on the ‘Generate password hash’ button.

Edit the config.local.php file and add the generated hash to it:

$CONF['setup_password'] = '0584cbe2b03cad2e29c8be0127361e37:d41ceb2689b747cf143d1809aec7b8e6bdde983e';

Replace the hash shown in the example with the one generated for your instance.

Save the config.local.php file, open the setup page once again and create a PostfixAdmin admin user account. The setup password in that page is the same password you used in the previous step, so fill the other required fields such as the admin email address and password, then click on the ‘Add admin’ button.

That’s it! The PostfixAdmin installation is complete.

Open http://your_server_IP/postfixadmin/login.php in your preferred web browser. You’ll see the login page:

Log in as the admin user and add the domains hosted on the server:

Once you do that, then you can create email addresses, set a mail quota, and so on:

That is everything you’ll need to install, configure, and start using your PostfixAdmin install on your Ubuntu 20.04 VPS.


This install process is very involved and is quite easy to mess up and end up with a botched install of Postfix, Dovecot, or both. However, if you have a Managed Ubuntu VPS hosting with us, you won’t need to do anything more than ask us to install it for you, Our team of support experts will completely install and configure all aspects of your server so that Postfix, Dovecot, and PostfixAdmin all work flawlessly. They can also help set up routine maintenance and optimize your server to maximize its speed.

We would appreciate you sharing this on social media if you found this tutorial useful. Or, you can write a comment letting us know how the install went, and if PostfixAdmin helped you manage your mail server more easily. Thanks!



 Kaynak: https://www.rosehosting.com/blog/how-to-install-a-mail-server-with-postfixadmin-on-ubuntu-20-04

 


Linux için önyükleyici olarak grub2 kullanılır.

arayüzü oldukça sade olduğu için değiştirmek isteyebilirsiniz.

bu nedenle burg temaları kullanılır.

Benim de kullanmakta olduğum burg temasını bu bağlantıdan indiriniz.

https://disk.yandex.com.tr/d/p3TCtLLGSjkWPA

root olarak konsolda

sudo mkdir -p /boot/grub/themes/

 

sudo tar -xvpf breeze.tar.gz -C /boot/grub/themes/

 

daha sonra grub default dosyasına tema dosyamızı ekleyelim.

sudo nano /etc/default/grub

açılan dosyanın en alt kısmına

GRUB_THEME=/boot/grub/themes/breeze/theme.txt

yazıp kaydedin.

ctrl+x tuşların basın kaydetmek için sorulan soruya evet  deyin.

temayı aktif etmek için son bir işlem kaldı.terminalde

sudo update-grub

komutunu verin.

Grub yapılandırma dosyası oluşturuluyor …
Bulunan tema: /boot/grub/themes/breeze/theme.txt
Bulunan linux kalıbı: /boot/vmlinuz-5.4.0-80-generic

işlem başarılı.

Yeni açılış temanızın Keyfini sürün 🙂

 

Proxmox VE (Virtual Environment) bilindiği üzere; Debian tabanlı, açık kaynak kodlu  Hypervizor Tip 1 (Bare Metal) bir sanallaştırma aracı. Bu araç ile ilgili detaylı bilgi için Proxmox VE adresini ziyaret edebilirsiniz.

Bu dökümanda kurulumunu yaptığımız Proxmox VE tarafından bize gönderilecek e-posta mesajlarının harici bir e-posta sunucusuna yönlendirilmesini sağlayacağız. 

 

 Yazının devamı için tıklayınız

 

13 Aralık 2017’de hayatını kaybeden Türkiye’de internetin yaygınlaşmasına öncülük eden önemli isimlerden biri olan Doç. Dr. Mustafa Akgül; ölümünün 4. yıldönümünde anılıyor. Bilindiği gibi, Doç. Dr. Mustafa Akgül, Linux Kullanıcıları Derneği’nin kurucularından ve onursal başkanıydı. 10 Mayıs 1948 tarihinde doğan Mustafa Akgül, 1970’te ODTÜ İnşaat Mühendisliği Bölümünden, 1974 yılında ODTÜ Matematik Bölümünden mezun oldu, 1981’de Waterloo University’den (Kanada) Kombinatorik ve Optimizasyon üzerine doktora derecesini aldı. ABD’de Delaware ve North Carolina State üniversitelerinde misafir öğretim üyesi olarak çalıştı. 1987’den itibaren Bilkent Üniversitesi öğretim üyesi olarak görev yaptı. Yurt dışında iken internet ile tanışıp kullanan Akgül, 12 Nisan 1993’te Türkiye internete bağlandıktan sonra ülkede internetin yaygınlaşmasına öncülük etti. İnternet konusunda basılı ilk Türkçe yayınlardan olan “İnternet: Bilgiye Erişimin Yeni Araç ve Olanakları”‘ adlı kitabı 1995 yılında yayımlandı.

İnternet Kurulu, Kamunet Teknik Kurulu, TOBB Sektör Kurulu ve Türkiye Bilişim Derneği yönetim kurulu üyeliği yaptı. 2000 yılında Linux Kullanıcıları Derneği’nin kurulmasının ardından ilk sekiz yılında yönetim kurulu başkanlığı görevini yürüttü. Derneğin Özgür Yazılım ve Linux Günleri (Şenliği), Akademik Bilişim Öncesi Kurslar, Linux Yaz Kampı etkinliklerinin öncüsü ve destekleyicisi oldu. Akgül Hoca, 13 Aralık 2017’de hayatını kaybetti.

 Aydın Akademik Bilişim 2016 dan kalan bir hatıra.

 



 

Çalışan canlı bir sistemi yedeklemek için onlarca yöntem var.

Bir tabiki opensource kaynak kullandığımız için yine açık kaynak yönemini değerlendireceğiz.

Çalışmakta olan Pfsense sistemi canlı halde iken uzak bir linux sistem üzerinden diske bire bir klonlayacağız..



teminalden pfsenseye login olalım.

8 e basıp pfsense komut satırına düşelim.

 

 
 

mount komutu ile bağlı diski görebiliriz.

Canlı olarak çalışan Pfsense bu komutla Linux sisteme bağlı olan diske birebir klonyacağız.

 

dd if=/dev/ad0 | ssh root@192.168.0.26 "dd of=/dev/sda"

 


  Hedef Linux Sistemimiz.



Klonlama işlemi biraz vakit alsada tamamlandı.

işlem ile ilgili bilgiler.

Hedef linux sistemimizi diskten boot ediyoruz.



İşte Sonuç.

Mac adresi değiştiği için Pfsense hedef sistemin ip adresi ile çalışmaya devam ediyor.

https://fatihyegin.files.wordpress.com/2013/07/pfsense_in-abc_si.pdf


[full-post]


 

Kaynak:  https://www.linuxbabe.com/mail-server/postfix-send-only-multiple-domains-ubuntu

In this article, I will show you how to set up Postfix as a send-only SMTP server on Ubuntu 20.04, 18.04, 16.04. I will first show you how to do it for a single domain, then you can apply the steps for multiple domains if you need to.

Use Case

You have a website/web application that needs to send transactional emails to users (such as password-reset email). Most likely, there’s no need for users to reply to these emails, or if they reply, the reply emails will be sent to your dedicated mail server. In this case, you can set up a send-only SMTP server on the web server using Postfix, which is a popular SMTP server software.

Prerequisites

In order to send emails from your server, port 25 (outbound) must be open. Many ISPs and hosting companies such as DigitalOcean block port 25 to control spam. I recommend using ScalaHosting, because it doesn’t block port 25 (outbound). Once you have a ScalaHosting server, install Ubuntu on it and follow the instructions below.

Setting up Postfix send-only SMTP server for multiple domains isn’t difficult actually. First, we need to configure it for one domain, then set it up for multiple domains.

Step 1: Install Postfix on Ubuntu

Run the following commands to install Postfix from the default Ubuntu repository.

sudo apt-get update

sudo apt-get install postfix -y

You will be asked to choose a mail server configuration type. Press the Tab key, then press Enter.

postfix send only smtp server

In the next screen, press Enter to select the default option: Internet Site.

postfix send only ubuntu

Next, enter your domain name for the system mail name, i.e. the domain name after @ symbol.

postfix send only multiple domains

Step 2: Configure Postfix

Setting the Postfix hostname

By default, Postfix SMTP server uses the OS’s hostname to identify itself when communicating with other SMTP server. However, the OS hostname might change, and some SMTP servers will reject your email if your hostname isn’t valid. So it’s a good practice to set the hostname directly in Postfix configuration file with the following command.

sudo postconf -e "myhostname = sendonly.yourdomain.com"

This hostname should have a DNS A record pointing to the IP address of your server.

Setting $mydomain Parameter

The $mydomain parameter specifies the local internet domain name. The default is to use $myhostname minus the first component. You can display the current value of $mydomain with:

postconf mydomain

It should be your apex domain name, like

linuxbabe.com

If it’s not displaying your apex domain name, then set the $mydomain parameter with:

sudo postconf -e "mydomain = yourdomain.com"

Setting $myorigin Parameter

The $myorigin parameter specifies the default domain name that is appended to sender and recipient addresses that have no @domain part. The default is to use the value of in the /etc/mailname file, as can be seen with:

postconf myorigin

Output:

myorigin = /etc/mailname

Then you can display the value in the /etc/mailname file.

cat /etc/mailname

Its value should be yourdomain.com without any subdomain.

echo "yourdomain.com" | sudo tee /etc/mailname

Restarting Postfix

Finally, we need to restart Postfix for the changes to take effect.

sudo systemctl restart postfix

Step 3: Set  PTR Record

You need to set a PTR record (aka, pointer record), which maps an IP address to an FQDN. It’s the counterpart to the A record. Many SMTP server will reject your email if your server’s IP address doesn’t have PTR record.

Because you get IP address from your hosting provider or ISP, not from your domain registrar, so you must set PTR record for your IP in the control panel of your hosting provider, or ask your ISP. For example, in ScalaHosting, you can set PTR record by opening a support ticket or use the live chat on their website. Although you can set PTR record to any hostname, for best practice, you should use the Postfix hostname in step 2

To see if your PTR record is set properly, run the following command. Replace 12.34.56.78 with your own IP address.

host 12.34.56.78

Note that if your server uses IPv6 address, it’s also a good idea to add AAAA record for your Postfix hostname and set PTR record for your IPv6 address.

Step 4: Install and Configure OpenDKIM

DKIM stands for DomainKeys Identified Mail. You can install OpenDKIM on your server and use it to add signatures to emails sent from your domain, with your private key. Receiving SMTP servers verify the signature by using the corresponding public key, which is published by you in the DNS. Adding DKIM signature is a must if you want your emails get into recipient’s inbox.

First install OpenDKIM from the default Ubuntu repository.

sudo apt-get install opendkim opendkim-tools

Then add postfix user to opendkim group.

sudo adduser postfix opendkim

Edit OpenDKIM main configuration file.

sudo nano /etc/opendkim.conf

Find the following lines.

#Canonicalization     simple
#Mode                 sv
#SubDomains           no

Uncomment them and replace simple with relaxed/simple. Change the mode from sv to s, because there’s no inbound email to verify signature.

Canonicalization     relaxed/simple
Mode                 s
SubDomains           no

Add the following lines at the end of this file. (On Ubuntu 18.04, the UserID is already set to opendkim)

#OpenDKIM user
# Remember to add user postfix to group opendkim
UserID             opendkim

# Map domains in From addresses to keys used to sign messages
KeyTable           refile:/etc/opendkim/key.table
SigningTable       refile:/etc/opendkim/signing.table

# A set of internal hosts whose mail should be signed
InternalHosts       /etc/opendkim/trusted.hosts

Save and close the file.

Create Signing Table, key Table and Trusted Hosts File

Create a directory structure for OpenDKIM.

sudo mkdir /etc/opendkim

sudo mkdir /etc/opendkim/keys

Change owner from root to opendkim and make sure only opendkim user can read and write to the keys directory.

sudo chown -R opendkim:opendkim /etc/opendkim

sudo chmod go-rw /etc/opendkim/keys

Create the signing table.

sudo nano /etc/opendkim/signing.table

Add the following line to the file. This means that if the From: header in an email contains example.com, then use the sendonly DKIM selector. You can change sendonly to your preferred DKIM selector name and it should be unique in your DNS.

*@example.com     sendonly._domainkey.example.com

Save and close the file. Then create the key table.

sudo nano /etc/opendkim/key.table

Add the following line. This means that for the sendonly DKIM selector, use the private key saved in /etc/opendkim/keys/example.com/sendonly.private to sign the email.

sendonly._domainkey.example.com    example.com:sendonly:/etc/opendkim/keys/example.com/sendonly.private

Save and close the file. Next, create the trusted hosts file.

sudo nano /etc/opendkim/trusted.hosts

Add the following lines to the newly created file.

127.0.0.1
localhost

*.example.com

The above means that messages coming from the above IP addresses and domains will be trusted and signed.

Generate Private/Public Keypair

We need to generate a private key to sign outgoing emails and a public key for receiving SMTP servers to verify the DKIM signature. Public key will be published in DNS.

Create a separate folder for the domain.

sudo mkdir /etc/opendkim/keys/example.com

Generate keys using opendkim-genkey tool.

sudo opendkim-genkey -b 2048 -d example.com -D /etc/opendkim/keys/example.com -s sendonly -v

The above command will create 2048 bits keys. -d (domain) specifies the domain. -D (directory) specifies the directory where the keys will be stored and we use sendonly as the selector (-s). Once the command is executed, the private key will be saved in sendonly.private and sendonly.txt will be the TXT record that contains public key.

Make opendkim as the owner of the private key.

sudo chown opendkim:opendkim /etc/opendkim/keys/example.com/sendonly.private

Add Public Key in DNS Records

Display the public key

sudo cat /etc/opendkim/keys/example.com/sendonly.txt

The string after the p parameter is the public key. In your DNS manager, create a TXT record for the second domain. Enter sendonly._domainkey in the Name field. Copy everything in the parentheses and paste into the value field. Delete all double quotes. (You can paste it into a text editor first, delete all double quotes, the copy it to your DNS manager. Your DNS manager may require you to delete other invalid characters, such as carriage return.)

postfix send only DKIM

Once the DNS record is published, enter the following command on your Ubuntu server to test your key.

sudo opendkim-testkey -d example.com -s sendonly -vvv

If everything is OK, you will see

key OK

If you see key not secure message, don’t panic. This is because DNSSEC isn’t enabled on your domain name.

Step 5: Connect Postfix with OpenDKIM

Postfix can talk to OpenDKIM via a Unix socket file. The default socket file used by OpenDKIM is /var/run/opendkim/opendkim.sock, as shown in /etc/opendkim.conf file. But the postfix SMTP daemon shipped with Ubuntu runs in a chroot jail, which means the SMTP daemon resolves all filenames relative to the Postfix queue directory (/var/spool/postfix). So we need to change the socket file.

Edit the OpenDKIM main configuration file.

sudo nano /etc/opendkim.conf

Find the following line:

Socket local:/var/run/opendkim/opendkim.sock

Replace it with the following line. (If you can’t find the above line, then add the following line.)

Socket local:/var/spool/postfix/opendkim/opendkim.sock

Create a directory to hold the OpenDKIM socket file and only allow opendkim user and postfix group to access it.

sudo mkdir /var/spool/postfix/opendkim

sudo chown opendkim:postfix /var/spool/postfix/opendkim

If you can find the following line in /etc/default/opendkim file.

SOCKET="local:/var/run/opendkim/opendkim.sock"

or

SOCKET=local:$RUNDIR/opendkim.sock

Change it to

SOCKET="local:/var/spool/postfix/opendkim/opendkim.sock"

After that, we need to edit Postfix main configuration file.

sudo nano /etc/postfix/main.cf

Add the following lines at the end of this file to connect Postfix with OpenDKIM.

# Milter configuration
milter_default_action = accept
milter_protocol = 6
smtpd_milters = local:opendkim/opendkim.sock
non_smtpd_milters = $smtpd_milters

Save and close the file. Restart OpenDKIM and Postfix.

sudo systemctl restart opendkim postfix

OpenDKIM won’t produce any message if it fails to restart. Run the following command to check its status. Make sure it’s running.

systemctl status opendkim

Step 6: Create SPF DNS Record

SPF (Sender Policy Framework) record specifies which hosts or IP addresses are allowed to send emails on behalf of a domain. In your DNS management interface, create a new TXT record like below. Use your own IPv4 address and IPv6 address of your server.

TXT  @   v=spf1 mx ip4:12.34.56.78 ip6:2600:3c01::f03c:93d8:f2c6:78ad ~all

Step 7: Set the From Address, From Name and Return-Path

You can set custom From address, From name and Return-Path in your website/web application. Let’s use WordPress as an example. You can add the following lines in your WordPress theme’s functions.php file to override the default From address, From name and return-path. Replace the red text as necessary.

// Function to change From email address
function wpb_sender_email( $original_email_address ) {
    return 'notifications@linuxbabe.com';
}

// Function to change sender name
function wpb_sender_name( $original_email_from ) {
    return 'LinuxBabe';
}

// Set return-path the same as From address
function fix_my_email_return_path( $phpmailer ) {
    $phpmailer->Sender = $phpmailer->From;
}

// Hooking up our functions to WordPress filters
add_filter( 'wp_mail_from', 'wpb_sender_email' );
add_filter( 'wp_mail_from_name', 'wpb_sender_name' );
add_action( 'phpmailer_init', 'fix_my_email_return_path' );

Save the file and you are done. (Be careful about the functions.php file. Do not add an empty line after ?> at the end of this file, or your WordPress XML sitemap can be corrupted.)

Step 8: Enable TLS Encryption for Outgoing Emails

By default, Postfix doesn’t use TLS encryption when sending outgoing emails. To enable TLS encryption, open the /etc/postfix/main.cf file and add the following two lines at the end of this file.

smtp_tls_security_level = may
smtp_tls_loglevel = 1

The first line enables TLS encryption for the Postfix SMTP client. The second line will log the TLS connection in /var/log/mail.log file, so you can check if TLS encryption is working. Save and close the file. Restart Postfix for the changes to take effect.

sudo systemctl restart postfix

Since Postfix doesn’t receive incoming emails, there’s no need to configure a valid TLS certificate for the Postfix SMTP daemon.

Some SMTP servers require you to use TLS. If not, they will reject your emails and you will see the following error message in the mail log.

Must issue a STARTTLS command first

Step 9: Testing Sender Score

Now go to https://www.mail-tester.com. You will see a unique email address. Send an email from your website on the Postfix SMTP server to this address and then check your score. As you can see, I got a perfect score. In the test result, you should check if your PTR record, SPF and DKIM record is valid.

imporve-email-server-reputation-dkim

You can also open the /var/log/mail.log file to check if TLS encryption is used. For example, the following line shows the connection to mail-tester.com is encrypted.

Anonymous TLS connection established to mail-tester.com[94.23.206.89]:25: TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)

What if Your Emails Are Still Being Marked as Spam?

I have more tips on email deliverability for you in this article: How to stop your emails being marked as spam. Although it will take some time and effort, your emails will eventually be placed in the inbox after applying these tips.

How to Configure Postfix Send-only SMTP Server For Multiple Domains

By default, Postfix allows you to use any domain name in the From header and return path address to send outgoing emails. If your server hosts multiple websites, you just need to create SPF DNS record for your other domains, which is very easy to do, and configure OpenDKIM for your other domains.

To configure OpenDKIM for other domains, you need to add the other domains in the signing table, key table and trusted hosts file like below.

Signing table (/etc/opendkim/signing.table)

*@example.com       sendonly._domainkey.example.com
*@example.net       sendonly._domainkey.example.net

Key table (/etc/opendkim/key.table)

sendonly._domainkey.example.com     example.com:sendonly:/etc/opendkim/keys/example.com/sendonly.private
sendonly._domainkey.example.net     example.net:sendonly:/etc/opendkim/keys/example.net/sendonly.private

Trusted hosts (/etc/opendkim/trusted.hosts)

127.0.0.1
localhost

*.example.com
*.example.net

Then generate the DKIM Private/Public keypair by following the same steps as mentioned above for other domains and add the DKIM public key in DNS. Restart OpenDKIM and you are done. Don’t forget to test your sender score.

Sending Emails From Another Server

There are two ways to allow other servers to send emails through your send-only Postfix SMTP server.

  • Use port 25 without SMTP authentication: This method requires the other server doesn’t block port 25 (outbound).
  • Use port 587 with SMTP authentication: If the other server blocks port 25 (outbound), you can use port 587.

Port 25 without SMTP Authentication

Run the following command to make Postfix listen on 0.0.0.0, so other servers can connect to the send-only Postfix SMTP server.

sudo postconf "inet_interfaces = all"

Then you need to add the IP address of the other server to the Postfix mynetworks parameter. Replace 12.34.56.78 with the real IP address.

sudo postconf "$(postconf mynetworks) 12.34.56.78"

Restart Postfix for the changes to take effect.

sudo systemctl restart postfix

Run the following commands to open port 25 (inbound) for the other server.

sudo ufw insert 1 allow in from 12.34.56.78 to any port 25 proto tcp

Now you can configure SMTP clients to use mta1.yourdomain.com and port 25 to send emails. You don’t need to specify username/password in the SMTP client.

Port 587 with SMTP Authentication

Open port 587 and 80 in firewall.

sudo ufw insert 1 allow in from 12.34.56.78 to any port 25 proto tcp
sudo ufw allow 80/tcp

Run the following command to make Postfix listen on 0.0.0.0, so other servers can connect to the send-only Postfix SMTP server.

sudo postconf "inet_interfaces = all"

Then you need to enable the submission service of Postfix so that the email client can submit emails to Postfix SMTP server. Edit the master.cf file.

sudo nano /etc/postfix/master.cf

In submission section, uncomment or add the following lines. Please allow at least one whitespace (tab or spacebar) before -o.  In postfix configurations, a preceding whitespace character means that this line is continuation of the previous line. (By default the submission section is commented out. You can copy the following lines and paste them into the file, so you don’t have to manually uncomment or add new text.)

submission     inet     n    -    y    -    -    smtpd
  -o syslog_name=postfix/submission
  -o smtpd_tls_security_level=encrypt
  -o smtpd_tls_wrappermode=no
  -o smtpd_sasl_auth_enable=yes
  -o smtpd_relay_restrictions=permit_sasl_authenticated,reject
  -o smtpd_recipient_restrictions=permit_mynetworks,permit_sasl_authenticated,reject
  -o smtpd_sasl_type=dovecot
  -o smtpd_sasl_path=private/auth

The above configuration enables the submission daemon of Postfix and requires TLS encryption. Plain text authentication will be rejected. The submission daemon listens on TCP port 587. STARTTLS is used to encrypt communications between SMTP client and the submission daemon.

Save and close the file. To enable SMTP authentication, we need to install Dovecot.

sudo apt install dovecot-core

Edit the authentication config file.

sudo nano /etc/dovecot/conf.d/10-auth.conf

Uncomment the following line.

disable_plaintext_auth = yes

It will disable plaintext authentication when there’s no SSL/TLS encryption. And if you want to use full email address (username@your-domain.com) to login, add the following line in the file.

auth_username_format = %Ln

Otherwise, you are able to login with username only (without @your-domain.com). Next, find the following line.

auth_mechanisms = plain

This line only enables the PLAIN authentication mechanism. LOGIN is another authentication mechanism you probably want to add to support older email clients.

auth_mechanisms = plain login

Save and close the file. Then edit the following file.

sudo nano /etc/dovecot/conf.d/10-master.conf

Change service auth section to the following so that Postfix can find the Dovecot authentication server.

service auth {
    unix_listener /var/spool/postfix/private/auth {
      mode = 0660
      user = postfix
      group = postfix
    }
}

postfix smtp auth ubuntu

Save and close the file. Restart Dovecot for the changes to take effect.

sudo systemctl restart dovecot

Next, we need to obtain a valid TLS certificate. We can easily obtain a free TLS certificate from Let’s Encrypt. Issue the following commands to install Let’s Encrypt client (certbot) on Ubuntu.

sudo apt install certbot

Then use the standalone plugin to obtain TLS certificate (assuming there’s no web server running on the Postfix SMTP server).

sudo certbot certonly --standalone --agree-tos --email you@example.com -d sendonly.yourdomain.com

After a while, you should see the following lines which means the certificate is successfully obtained. You can also see the directory under which your cert is stored.

Next, we need to run the following two commands to specify the location of TLS certificate and private key in Postfix configuration file. Your Let’s Encrypt certificate and private key are stored under /etc/letsencrypt/live/sendonly.your-domain.com/ directory.

sudo postconf "smtpd_tls_cert_file = /etc/letsencrypt/live/sendonly.your-domain.com/fullchain.pem"

sudo postconf "smtpd_tls_key_file = /etc/letsencrypt/live/sendonly.your-domain.com/privkey.pem"

Restart Postfix for the changes to take effect.

sudo systemctl restart postfix

Now you can configure SMTP clients to use sendonly.yourdomain.com and port 587 to send emails. Use TLS encryption type and plain as authentication mode. You need to create email account on the SMTP server. That’s very simple. Use the adduser command to add a user.

sudo adduser user1 --no-create-home

Then set a password for this user.

sudo passwd user1

The email address will be user1@yourdomain.com.

Troubleshooting

Email not Signed by DKIM

If your message is not signed and DKIM check failed, you may want to check postfix log (/var/log/mail.log) to see what’s wrong in your configuration. If you see the following message in the mail log,

warning: connect to Milter service local:opendkim/opendkim.sock: No such file or directory

you may want to check if the opendkim systemd service is actually running.

systemctl status opendkim

If opendkim is running and you still see the above error, you might need to change smtpd_milters = local:opendkim/opendkim.sock to smtpd_milters = local:/opendkim/opendkim.sock in /etc/postfix/main.cf file.

Must Issue a STARTTLS Command First

If you see the following error in the mail log (/var/log/mail.log), it’s probably because the TLS certificate is not specified correctly in /etc/postfix/main.cf file.

Must issue a STARTTLS command first (in reply to MAIL FROM command))

fatal: no SASL authentication mechanisms

If you see the following error in the mail log (/var/log/mail.log), it’s probably because you forgot to restart dovecot (sudo systemctl restart dovecot).

warning: SASL: Connect to private/auth failed: No such file or directory
fatal: no SASL authentication mechanisms

Also, check if Dovecot is running.

sudo systemctl status dovecot

Sending Bulk or Mass Emails

Can you use this SMTP server to send bulk or mass emails?

Yes, but you should send bulk email to legitimate subscribers only, that is to say, the recipients should have signed up for your mailing list. You should never send spam (unsolicited bulk email), or you SMTP server will surely be blacklisted. Before sending bulk email, I highly recommended following the advice in this article: How to Stop Your Emails Being Marked as Spam.

Disable Receiving Email in Postfix

By default, Postfix SMTP server listens on all active interfaces on the machine. Since the Postfix SMTP server is only used for sending transactional emails to users, you can block inbound connection to TCP port 25, so bad actors can’t send spam to it. Since we added the a whitelist for port 25, legitimate users won’t be affected.

Removing Sensitive Information from Email Headers

By default, Postfix SMTP server will add a Received: email header, recording the IP address of the client, which can leak the IP address of your website (If it’s behind CDN). You can tell Postfix to ignore it. Create a header check file.

sudo nano /etc/postfix/smtp_header_checks

Put the following lines into the file.

/^Received:/            IGNORE

Save and close the file. Then edit the Postfix main configuration file.

sudo nano /etc/postfix/main.cf

Add the following line at the end of the file.

smtp_header_checks = regexp:/etc/postfix/smtp_header_checks

Save and close the file. Then run the following command to rebuild hash table.

sudo postmap /etc/postfix/smtp_header_checks

Reload Postfix for the change to take effect.

sudo systemctl reload postfix

Now Postfix won’t include that sensitive information in email headers.

Auto-Renew TLS Certificate

You can create Cron job to automatically renew TLS certificate. Simply open root user’s crontab file.

sudo crontab -e

Then add the following line.

@daily certbot renew --quiet

Save and close the file.

Conclusion

I hope this tutorial helped you set up a Postfix send-only SMTP server on Ubuntu for multiple domains. As always, if you found this post useful, then subscribe to our free newsletter to get more tips and tricks. Take care 🙂

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VMWARE ESXI ONLINE YEDEKLEME VE FREENAS KURULUMU

 Kaynak site: http://ahmetorhan.com/vmware-esxi-online-yedekleme-freenas-kurulumu/

 

Bilgi işlem yöneticilerinin en korkulu rüyası günün birinde sunucularının çökmesi yada herhangi bir sebep sonucu erişilemez olmasıdır. Onlarca telefon kuyrukta bekler, çökmenin travmasıyla ömrünüzden birkaç yıl yemiş olmasına rağmen telefonda sakin sakin durumu anlatmaya çalışırsınız ..

Yazılımsal bir çökme ise elinizde daha önceden almış olduğunuz disk imajlarına güvenirsiniz ve dün geceki yedeğe. İmajı geri getirmeniz ve yedekteki dosyaları restore etmeniz en iyi ihtimalle tüm gününüzü alabilir. Eğer ki donanımınızda bir sorun oluştuysa durum daha vahimdir. Kullandığınız server yerine bir server temin etmeniz gerekir ve imaj dosyalarını bu servera yükleyemeyeceğinize göre(aynı donanım olmaması durumunda) yeniden kurulum yaparsınız ve active directory olan bir sistemde eğer ad yedekleri de çalışmıyorsa tüm terminalleri elle tekrar domaine sokmanız gerekir ki bu durumda birkaç gün sistemi tam olarak toparlayamazsınız.

Çökme bir kere başınıza geldiğinde aksiliklerinde üst üste geldiğini görmek pek vaktinizi almaz. Son aldığınız imajın çalışmaması, active directory system state yedeğinin sorun çıkarması(kesinlikle %100 güvenmeyin). Yedeklerin çok uzun sürede restore edilmesi vs..vs..

Kritik uygulamaların çalıştığı sistemlerde bu tür felaket senaryolarına karşı cluster mimarisi kurulur. Sunuculardan birinin çökmesi durumunda diğer sunucu görevi devralır ve sistem kesintisiz çalışmaya devam eder(high availability) .

Diyelim ki 100-200 bilgisayardan oluşan bir sisteminiz var ve orta ölçekli bir kuruluşsunuz. Active/Passive cluster mimarisini sisteme kurmak istiyorsunuz, bunun için iki sunucu ve Fc-SAN donanımlarına ödeyeceğiniz miktar 20-30 bin dolar arasındadır. Bu miktar birçok orta ölçekli kurumun bütçesini aşacaktır.

Sunucularınızın ve datalarının yedeğinin alınmasını bir çökme durumunda alınan yedekten herhangi bir sunucu donanımı ile sisteminizi geri yüklemek ve bu işlemi en fazla 10 dk yapmak için aşağıdaki yöntemi kullanabiliriz.

Mimarimiz şu şekilde.

 Bu mimaride vmware esxi(ücretsiz) ile sanal sunucuları kuracağız ve yedeklerini nas üzerine alacağız.
Sistemin çökmesi durumlarda ise başka bir sunucudan nas üzerindeki server imajlarını attach ederek
sistemleri çalıştıracağız. Tabiki nas tcp/ip üzerinden 1gbit bağlantı ile erişim yaptığından dosya yazma ve
okumalarda yavaşlık olacaktır.
1. FREENAS KURULUMU
Freenas ile iscsi protokolünü kullanarak bir SAN (Storage Area Network) kurulumu yapacağız. Freenas
kurulumu yapılacak olan sunucu(ya da pc) disk okuma yazma performansı açısından değerlendirilmeli ve
kullanılacak diskler buna göre seçilmelidir.
“San ve Nas kavranları bazı durumlarda birbiriyle örtüşür hale geldi.
Örneğin freenas NAS yönetim yazılımı, iscsi ise bir SAN protokolü. Bu nedenle oluşturduğumuz yapı
esasında SAN dır.”
1. http://freenas.org/downloads adresinden uygun ortam dosyasını indirip freenas kurulumu yapalım. (Biz
uygulamamızda vmware üzerine kurduk. 120 gb sanal disk alanı tanımladık.)
2. Freenas'a ip üzerinden erişelim. (ip adresi freenas kurulu sistemin konsolunda yazıyor).

 

3. Disk - Managment - Add Disk


4. Storage için kullanılacak Diski seçiyoruz.
Preformatted file system den ZFS storage pool device seçiyoruz

Disks - ZFS - Virtual Device -Add Device
 

6.
Virtual Device ekliyoruz.
 

7. Disks - ZFS - Managment - Addpool

8.
Services- iSCSI Target

9. Services-iscsi target- Portals -Add
 

10
Services-iSCSI Target- Initiators -Add

11.
Services - iSCSI Target - Targets - Extend - Add Extend

12.
Services - iSCSI Target - Targets - Target - Add Target

13.
Extent ve Target Görünümü

14. iSCSI Base name değerini değiştirip save and restart diyoruz ve kurulumuz tamam.

 
VMWARE YAPILANDIRMASI
 


2. iscsi Initiator Properties - Dynamic Discovery – Add
 

3.
Iscsi Target Adaptörlerini ara.


 


4. Storage olarak ekle

Sonraki adımda Storage için bir isim belirliyoruz(Örn : exsan ) ve kurulumu tamamlıyoruz. Artık Vmware
esxi sunucumuz oluşturmuş olduğumuz iSCSI - SAN veri deposunu /vmfs/volumes/exsan(storage ismi)
olarak görecektir.
Yedeklerimizi bu path üzerine aldıracağız.
Vmware esx sürümünde vmotion tekniğini temel alarak sanal sunucu ve disklerimizi istediğimiz sunucuya
taşıyabiliyoruz, çökme durumunda sunucular otomatik olarak storage üzerindeki imajları attach ederek
çalışmaya devam ediyor ve fiziksel sunucular arasında yük dengeleme yapılabiliyor. Ancak başta dadediğimiz gibi lisans ücretlerinin fazla olması ve böyle bir yatırım yapamayacak olmamızdan dolayı biz esxi
sürümü üzerinde çalışmakta olan bir sanal sunucunun online yedeğini nasıl alacağımıza bakacağız.
Esxi kurulumunun yapıldığını ve sanal sunucuların kurulduğunu varsayarak devam ediyoruz.

1. Vmware karşılama ekranında Alt+F1 e basıyoruz. (Karşılama Ekranı için Alt+F2)
2. unsupported yazıyoruz
3. Parola bilgisini giriyoruz ve karşımıza konsol çıkıyor. (~#)
4. Online yedekleme için GhettoVCB.sh scriptini indiriyoruz.
5.
~# wget http://communities.vmware.com/servlet/JiveServlet/download/8760-49-32036/ghettoVCB.sh
6.
# cat ghettoVCB.sh
(Eğer ghettoVCB.sh içerisindeki satırların sonunda ^M karakteri varsa script çalışmayacaktır. Bu karakter
windows new line'ı tanımlar.)
7. Şimdi Script içinde birkaç küçük değişiklik yapacağız.

# vi ghettoVCB.sh
LAST_MODIFIED_DATE=11/14/2009
# vm sanal sunucu dosyalarının yedekleneceği yol. Oluşturduğumuz SAN' a yedekliyouz
VM_BACKUP_VOLUME=/vmfs/volumes/exsan/vmyedek
DISK_BACKUP_FORMAT=zeroedthick
# Yedekleme geçmişi.
VM_BACKUP_ROTATION_COUNT=3
# Yedek almadan önce sanal makineyi kapat.
# 1=on, 0 =off
POWER_VM_DOWN_BEFORE_BACKUP=0
Sadece bu değişikleri yapmamız yeterli
8. Dosyayı çalıştırılabilir yapalım.
# chmod +x /vmfs/volumes/deppo/ghettoVCB.sh
9. Hangi sanal sunucuların yedekleneceği bilgisini vermedik. Bunun için bir dosya oluşturup yedeklenmesini
istediğimiz sanal sunucu inventory isimlerini yazıyor.
Windows 2003 Server Ent ve Freebsd 7.2 sanal sunucularımın yedeklenmesini istiyorum.

# vi yedek_liste
Windows 2003 Server Ent
Freebsd 7.210. 

 

Yedeklemeyi başlatalım
# /vmfs/volumes/deppo/ghettoVCB.sh -f yedek_liste


Bu işlemleri zamanlanmış görev olarak yapmak için


/etc/rc.local dosyasının sonuna aşağıdaki satırları ekliyoruz ve reboot ediyoruz. (Pazartesi-cumartesi
arasında her gece 12 de yedek alacak)
/bin/kill $(cat /var/run/crond.pid)
.
/bin/echo "0 0 * * 1-6 /vmfs/volumes/deppo/ghettoVCB.sh -f /vmfs/volumes/deppo/yedek_liste
> /vmfs/volumes/deppo/ghettoVCB-yedek-\$(date +\\%s).log" >> /var/spool/cron/crontabs/root
/bin/busybox crond

Eğer ki, cron yerine Windows altında zamanlanmış görev olarak yedekleme yapmak istiyorsanız vmware
üzerindeki ssh servisini aktif hale getirip aşağıdaki adımları uygulamalısınız.
1. Ssh servisini aktif hale getirmek için : 

http://www.yellow-bricks.com/2008/08/10/howto-esxi-and-ssh/


2. http://the.earth.li/~sgtatham/putty/latest/x86/plink.exe adresinden programı indirelim
3. plink.exe dosyasını c:\ altına kopyalayalım ve aşağıdaki komutu çalıştıralım. Bu sayede vmware’e ssh ile
bağlanıp yukarıdaki yedek alma komutunu giriyoruz. Plink’in güzel tarafı ise bunu tek satırda yapabilmemiz
 

c:\plink.exe -l root 192.168.0.9 -pw vmparolanız /vmfs/volumes/deppo/ghettoVCB.sh –f
/vmfs/volumes/deppo/ghettoVCB.sh -f yedek_liste

 
Artık bu komutu Windows altında zamanlanmış görev olarak çalıştırabilirsiniz.
Yedekleme işlemi bittikten sonra başka bir sunucuya Vmware esxi kurulumu yapıp, oluşturduğumuz iscsi
targetı ekleyebilir ve buradaki yedeklenen dosyayı attach ederek herhangi bir felaket anında sistemin diğer
sunucudan çalışmasını sağlayabiliriz.


Yedek Sunucumuz : esxi2
esxi2 de Storage Adapter ve iscsi storage eklenmiş durumda iken Freenas üzerindeki sanal sunucu dosyasını
attach ediyoruz(Add Ito Inventory) ve windowsumuz artık yeni sunucuda çalışıyor.


Kaynaklar:

https://docplayer.biz.tr/454207-Vmware-esxi-online-yedekleme-ve-freenas-kurulumu.html

http://www.freenas.org http://communities.vmware.com/docs/DOC-8760

Ahmet orhan 

ahmetorhan@yahoo.com

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