How to Exclude or Include Postfix from Future Updates on CWP / AlmaLinux 8

Hello,

I wanted to share a useful server maintenance note for anyone using CWP / Control Web Panel on AlmaLinux 8.

Sometimes, after a system update, Postfix-related packages can create dependency issues, especially when postfix and postfix-mysql need to stay on compatible versions.

In this case, it may be safer to temporarily exclude or lock Postfix packages from future updates until you are ready to update them carefully.

First, check the currently installed Postfix packages:

Example output may look like:

It is important to keep related Postfix packages compatible with each other.

Option 1: Use DNF Versionlock

This is usually the cleaner method because it locks the currently installed package versions.

First, make sure the versionlock plugin is available:

If that package is not available, try:

Then lock Postfix and Postfix MySQL packages:

Check the active version locks:

Now future system updates should not upgrade those locked Postfix packages.

You can safely run updates as usual:

Postfix should remain on the locked version.

How to Allow Postfix Updates Again

When you want to include Postfix in future updates again, remove the version lock:

Then check that the locks were removed:

After that, Postfix can be updated again with:

or with a normal full update:

Option 2: Exclude Postfix in dnf.conf

Another method is to exclude Postfix packages globally from DNF updates.

Edit the DNF configuration file:

Add this line under the main section:

Then save the file.

After this, DNF will skip Postfix packages during updates.

To confirm, you can run:

If you later want to allow Postfix updates again, edit the file:

Remove or comment this line:

For example:

Then run:

Important Notes

Do not update only one Postfix package while leaving related packages behind.

For example, avoid updating only:

while leaving:

on a different version.

On CWP servers, Postfix is connected with mail services and MySQL maps, so mismatched versions can cause mail service or dependency problems.

A good safety check before and after updates is:

You can also check failed services with:

Quick Summary

To exclude Postfix from future updates using versionlock:

To include Postfix in updates again:

This is useful when you want to avoid unexpected Postfix updates on a production CWP mail server until you are ready to handle the update safely.