Linux Postfix Troubleshooting

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Linux Postfix Troubleshooting

 Question : Some users of the monitoring app have reported issues with xFusionCorp Industries mail server. They have a mail server in Stork DC where they are using postfix mail transfer agent. Postfix service seems to fail. Try to identify the root cause and fix it.

Please Note :-  Perform the below commands based on your question  server,  user name & other details might differ . So please read task carefully before executing. All the Best 👍

Solution:  

1. Login on   Mail  server as per the task and switch root user

thor@jump_host /$ ssh groot@stmail01

The authenticity of host 'stmail01 (172.16.238.11)' can't be established.

ECDSA key fingerprint is SHA256:SySamszyWhhLGFiybhGBqfrr8g55wS/3e37ZpBOvICs.

ECDSA key fingerprint is MD5:6d:31:18:2a:f9:07:f3:29:dd:0a:d3:1f:6e:04:0a:db.

Are you sure you want to continue connecting (yes/no)? yes

Warning: Permanently added 'stmail01,172.16.238.17' (ECDSA) to the list of known hosts.

groot@stmail01's password:

[groot@stmail01 ~]$ sudo su -

 We trust you have received the usual lecture from the local System

Administrator. It usually boils down to these three things:

     #1) Respect the privacy of others.

    #2) Think before you type.

    #3) With great power comes great responsibility.

 [sudo] password for groot:

[root@stmail01 ~]#

2. Start postfix service , check status with -l for details error output 

[root@stmail01 ~]# systemctl start postfix

Job for postfix.service failed because the control process exited with error code. See "systemctl status postfix.service" and "journalctl -xe" for details.

[root@stmail01 ~]#

[root@stmail01 ~]# systemctl status postfix -l

● postfix.service - Postfix Mail Transport Agent

   Loaded: loaded (/usr/lib/systemd/system/postfix.service; enabled; vendor preset: disabled)

   Active: failed (Result: exit-code) since Tue 2021-06-22 14:55:33 UTC; 6s ago

  Process: 383 ExecStart=/usr/sbin/postfix start (code=exited, status=1/FAILURE)

  Process: 382 ExecStartPre=/usr/libexec/postfix/chroot-update (code=exited, status=0/SUCCESS)

  Process: 379 ExecStartPre=/usr/libexec/postfix/aliasesdb (code=exited, status=75)

 

Jun 22 14:55:31 stmail01.stratos.xfusioncorp.com systemd[1]: Starting Postfix Mail Transport Agent...

Jun 22 14:55:31 stmail01.stratos.xfusioncorp.com aliasesdb[379]: /usr/sbin/postconf: fatal: parameter inet_interfaces: no local interface found for ::1

Jun 22 14:55:32 stmail01.stratos.xfusioncorp.com aliasesdb[379]: newaliases: fatal: parameter inet_interfaces: no local interface found for ::1

Jun 22 14:55:32 stmail01.stratos.xfusioncorp.com postfix/sendmail[381]: fatal: parameter inet_interfaces: no local interface found for ::1

Jun 22 14:55:32 stmail01.stratos.xfusioncorp.com postfix[383]: fatal: parameter inet_interfaces: no local interface found for ::1

Jun 22 14:55:33 stmail01.stratos.xfusioncorp.com systemd[1]: postfix.service: control process exited, code=exited status=1

Jun 22 14:55:33 stmail01.stratos.xfusioncorp.com systemd[1]: Failed to start Postfix Mail Transport Agent.

Jun 22 14:55:33 stmail01.stratos.xfusioncorp.com systemd[1]: Unit postfix.service entered failed state.

Jun 22 14:55:33 stmail01.stratos.xfusioncorp.com systemd[1]: postfix.service failed.

[root@stmail01 ~]#

3. As we identify the issue in configuration file edit and do the changes

[root@stmail01 ~]# cat /etc/postfix/main.cf |grep inet_interface

# The inet_interfaces parameter specifies the network interface

inet_interfaces = all

#inet_interfaces = $myhostname

#inet_interfaces = $myhostname, localhost

inet_interfaces = localhost

# the address list specified with the inet_interfaces parameter.

# receives mail on (see the inet_interfaces parameter).

# to $mydestination, $inet_interfaces or $proxy_interfaces.

# - destinations that match $inet_interfaces or $proxy_interfaces,

# unknown@[$inet_interfaces] or unknown@[$proxy_interfaces] is returned

[root@stmail01 ~]#

[root@stmail01 ~]# vi /etc/postfix/main.cf

[root@stmail01 ~]# cat /etc/postfix/main.cf |grep inet_interface

# The inet_interfaces parameter specifies the network interface

inet_interfaces = all

#inet_interfaces = $myhostname

#inet_interfaces = $myhostname, localhost

#inet_interfaces = localhost

# the address list specified with the inet_interfaces parameter.

# receives mail on (see the inet_interfaces parameter).

# to $mydestination, $inet_interfaces or $proxy_interfaces.

# - destinations that match $inet_interfaces or $proxy_interfaces,

# unknown@[$inet_interfaces] or unknown@[$proxy_interfaces] is returned

[root@stmail01 ~]#

4. Post configuration saved start the services and check the status 

[root@stmail01 ~]# systemctl start postfix

[root@stmail01 ~]#

[root@stmail01 ~]# systemctl status postfix

● postfix.service - Postfix Mail Transport Agent

   Loaded: loaded (/usr/lib/systemd/system/postfix.service; enabled; vendor preset: disabled)

   Active: active (running) since Tue 2021-06-22 14:59:45 UTC; 16s ago

  Process: 475 ExecStop=/usr/sbin/postfix stop (code=exited, status=0/SUCCESS)

  Process: 504 ExecStart=/usr/sbin/postfix start (code=exited, status=0/SUCCESS)

  Process: 503 ExecStartPre=/usr/libexec/postfix/chroot-update (code=exited, status=0/SUCCESS)

  Process: 501 ExecStartPre=/usr/libexec/postfix/aliasesdb (code=exited, status=0/SUCCESS)

 Main PID: 575 (master)

   CGroup: /docker/050a5d787eedc1731e809d002d6f548be599723012d6b80fd344d807a45da4db/system.slice/postfix.service

           575 /usr/libexec/postfix/master -w

           576 pickup -l -t unix -u

           └─577 qmgr -l -t unix -u

 Jun 22 14:59:45 stmail01.stratos.xfusioncorp.com systemd[1]: Starting Postfix Mail Transport Agent...

Jun 22 14:59:45 stmail01.stratos.xfusioncorp.com postfix/master[575]: daemon started -- version 2.10.1, configuration /e...fix

Jun 22 14:59:45 stmail01.stratos.xfusioncorp.com systemd[1]: Started Postfix Mail Transport Agent.

Hint: Some lines were ellipsized, use -l to show in full.

[root@stmail01 ~]#

5. validate the task by telnet the port 25 

thor@jump_host /$ telnet stmail01 25

Trying 172.16.238.17...

Connected to stmail01.

Escape character is '^]'.

220 stmail01.stratos.xfusioncorp.com ESMTP Postfix

Connection closed by foreign host.

thor@jump_host /$


6. Click on Finish & Confirm to complete the task successful

Happy Learning!!!!


Apart from this if you need more clarity,  I have made a  tutorial video on this , please go through and share your comments. Like and share the knowledge



Post a Comment

4 Comments

  1. How to know password for stmail01 ?

    ReplyDelete
    Replies
    1. you can get all the servers password from wiki page. https://kodekloudhub.github.io/kodekloud-engineer/docs/projects/nautilus

      apart form that i have shared all password for you

      Server Name IP Hostname User Password Purpose
      stapp01 172.16.238.10 stapp01.stratos.xfusioncorp.com tony Ir0nM@n Nautilus App 1
      stapp02 172.16.238.11 stapp02.stratos.xfusioncorp.com steve Am3ric@ Nautilus App 2
      stapp03 172.16.238.12 stapp03.stratos.xfusioncorp.com banner BigGr33n Nautilus App 3
      stlb01 172.16.238.14 stlb01.stratos.xfusioncorp.com loki Mischi3f Nautilus HTTP LBR
      stdb01 172.16.239.10 stdb01.stratos.xfusioncorp.com peter Sp!dy Nautilus DB Server
      ststor01 172.16.238.15 ststor01.stratos.xfusioncorp.com natasha Bl@kW Stork DC Storage Filer
      stbkp01 172.16.238.16 stbkp01.stratos.xfusioncorp.com clint H@wk3y3 Nautilus Backup Server
      stmail01 172.16.238.17 stmail01.stratos.xfusioncorp.com groot Gr00T123 Nautilus Mail Server
      jump_host Dynamic jump_host.stratos.xfusioncorp.com thor mjolnir123 Jump Server to Access Stork DC
      jenkins 172.16.238.19 jenkins.stratos.xfusioncorp.com jenkins j@rv!s Jenkins Server for CI/CD

      Delete
  2. How did you find the problem is with main.conf using logs?

    ReplyDelete
    Replies
    1. Through Log you can find the problem , Even we can check the Error code. by See "systemctl status postfix.service" and "journalctl -xe" for more details you can refer my video to troubleshot the error https://youtu.be/DsgjN1GXXJ0

      Delete

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