How to stop SPAM with Postfix RBL

To stop spam using RBL in postfix, edit


Restart postfix

See postfix […]

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Postfix enable Maildir

To enable postfix, run

You can do it by editing /etc/postfix/


if home_mailbox entry already in file, then modify instead of adding a new entry. Virtual Mailbox If you are using virtual mailbox, make sure you spedify folder in your virtual_mailbox_maps. Here is what i have in

in […]

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fatal: open /etc/postfix/ Permission denied

On a CentOS server, when sending mail from PHP scripts, mail failed to work. On checking postfix log file (/var/log/maillog), i see following error.

To fix this, disable selinux

To permanantly disable SELinux, run


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Postfix email forward

postfix mail server

On an Ubuntu Server, i done following to setup email forwarding. Install postfix

Edit /etc/postfix/, add following


Create Virtual mailbox


Create alias file, used for mail forwarding


Wth above configuration, mail coming to [email protected] will get forwarded to [email protected] Email coming to [email protected] get delivered […]

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iredmail increase mail attachment size

Default mail attachment size in iredmail is 10 MB. To increase mail attachment size, login to server as user root, run following commands

Here 104857600 is 100 MB in bytes (100 * 1024 * 1024). Change this as required. Sending very large file using mail attachment is not recommended, it is better use file […]

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Zimbra webmail not working on port 80/443

On Zimbra mail server, webmail stopped working on Port 80/443. Admin interface worked properly on url https://hostname:7071/. There is no errors displayed under monitor tab of Zimbra Admin. To fix, run

After running this, netstat -lntp start showing nginx running on port 80 and 443


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Zimbra Mail Server CentOS firewall settings

On CentOS 7 server with firewalld running, used following command to open ports used by Zimbra Mail Server.

See Zimbra, firewall-cmd […]

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Zimbra redirect webmail http to https

After Zimbra mail server installed, webmail work on url https://SERVER-HOSTNAME-HERE/ If you access webmail with out HTTPS, it won’t work. To set HTTP to redirect to HTTPS, login to server as root, switch to user zimbra


Wait few minutes, HTTP link will redirect to HTTPS.

You need to wait few minutes […]

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Install SSL Certificate on Zimbra mail server

Zimbra SSL install

To install SSL certificate for Zimbra Mail Server, login to server, switch to user zimbra

Now create file commercial.key, paste your Private key.

In commercial.crt, paste your SSL certificate.

Create commercial_ca.crt with content of your ca-bundle file.

Verify SSL cerificate

If SSL verified sucessfully, you can install it with command […]

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