Validating Multi-Instance Postfix
[Ref: OpenBSD 5.4, Postfix 2.11.0 (from ports)]
In general, the process for reviewing, validating the performance of your multi-instance Postfix Server is the same that would be used for a single instance Postfix Server, which we have already referenced in Validating Mail Service
- connecting to smtp, pop3, imap
- SSL/TLS Transport
The key issue with the general diagnostics tools, it that it assumes a single running instance and refers to the ‘default’ postfix configuration settings/file.
To let us manage, review multi-instance performance in a consistent command-line sequence, use the postmulti utility in the following manner.
postmulti -i instance-name -p postfix-command
postmulti -i instance-name -x shell-command
To use the postfix command-line options but to a specific instance “instance-name“ we would use the following examples:
postmulti -i instance-name -p stop
postmulti -i instance-name -p start
postmulti -i instance-name -p reload
postmulti -i instance-name -p flush
To use the postfix utilities such as mailq or postqueue we would use the following examples:
postmulti -i instance-name -x mailq
postmulti -i instance-name -x postqueue -p
postmulti -i instance-name -x qshape
All instance reporting
To run postfix commands against all instances, we use postmulti without an instance specification.
The below command, will run mailq for each instance.
postmulti -x mailq
For cursor style applications such as qshape, I find using the below command incantation a better alternative