CIDR format table in Postfix doesn't work.

  • Postfix supports CIDR tables but it is not required to run postmap command on /etc/postfix/network_table file. CIDR format is just a text format. It is not required to transform it to another format. To enable a CIDR table, create a file with the network enties which should be allowed or denied access to the mail server
  # cat /etc/postfix/network_table 
  # Rule order matters. Put more specific whitelist entries
  # before more general blacklist entries.
  127.0.0.0/8 OK
  10.0.0.0/24 OK
  192.168.0.0/24 OK
  172.16.0.0/24 REJECT
  • Add following lines in /etc/postfix/main.cf
   mynetworks = cidr:/etc/postfix/network_table
   smtpd_client_restrictions = cidr:/etc/postfix/network_tabl
  • Restart postfix service
  # service postfix restart
  • For more information on cidr_table consult the man page man cidr_table.

Comments

Post a Comment

Popular posts from this blog

How to clean all the foreman task and locked task

1.- First make su to postgres user su -s /bin/bash - postgres  2.-Execute psql psql  3.- connect to the foreman database \c foreman;  4.- Delete all the foreman task and foreman task locks delete from foreman_tasks_tasks;  delete from foreman_tasks_locks;  5.- Quit from postgres and exit \q  exit  6. Restart all the services for s in {qpidd,pulp_celerybeat,pulp_ resource_manager,pulp_workers, httpd}; do sudo service $s restart; done  Update in todays foreman you can clean the task using the following command: foreman-rake foreman_tasks:cleanup
Read more

CentOS 7 Server Hardening Guide

CentOS 7 Server Hardening Guide 1. System Settings – Disk Partitioning and Post installation 1.1 Disk Encryption with Kickstart The easiest way to encrypt a partition is during Kickstart installation. This can be achieved by adding the –encrypted and –passphrase= options to the definition of a physical LVM volume. Our Kickstart template is provided below. Note that the template requires a 32GB disk. #version=CentOS7.5 # System authorisation information auth --enableshadow --passalgo=sha512 # Use CDROM installation media cdrom ignoredisk --only-use=sda # Keyboard layouts keyboard --vckeymap=gb --xlayouts='gb' # System language lang en_GB.UTF-8 # SELinux selinux --enforcing # Network information network --bootproto=dhcp --device=eth0 --onboot=on --activate network --hostname=ks-c7.example.com # Plaintext root password: PleaseChangeMe rootpw --iscrypted $6$nS0mBJyS$q/QgCof5unWrT9W3qngTISueSDhDHVNntDqd8sOcgmHp2lq4f/niUbjCmoEzaf3EWQ2x3z/k0eIZa
Read more

How to restrict users to send only mail to the local domain in Zimbra

How to restrict users to send only mail to the local domain in Zimbra 1. Open file /opt/zimbra/conf/zmconfigd/smtpd_recipient_restrictions.cf and add this line below reject_non_fqdn_recipient. This is example on my system permit_sasl_authenticated check_sender_access lmdb:/opt/zimbra/postfix/conf/restricted_senders permit_mynetworks 2. Open file /opt/zimbra/conf/zmconfigd.cf and add those lines before RESTART mta. This is example on my system POSTCONF smtpd_restriction_classes local_only POSTCONF local_only FILE postfix_check_recipient_access.cf RESTART mta 3. Create a file /opt/zimbra/conf/postfix_check_recipient_access.cf and add the following line.  check_recipient_access lmdb:/opt/zimbra/postfix/conf/local_domains, reject 4. Create a file "/opt/zimbra/postfix/conf/restricted_senders" and list all the users, whom you want to restrict. Follow this syntax: user@yourdomain.com local_only 5. Create a file "/opt/zimbra/postfix/con
Read more