Sockets in a persistent volume

[bcroq]

We get errors when backuping the persistent volume used for /var/spool/mail because it contains a lot of sockets.

Is it a good idea to put these sockets in a persistent volume?

[bokysan]

because it contains a lot of sockets

Can you provide a bit more info? Postfix is directed to use /var/spool/mail as the mail_spool_directory.

I am not familiar with any configuration which would direct postfix to put the socket connections elsewhere.

[bcroq]

I use the 3.0.0 chart with persistence enabled.

Here is the configuration:

mail:
  fullnameOverride: mail
  config:
    general:
      ALLOWED_SENDER_DOMAINS: example.com
      RELAYHOST: "[mailhog.ns.svc.cluster.local]:1025"
      TZ: Europe/Paris
  persistence:
    enabled: true
    size: 100Mi
    existingClaim: my-claim

Here is the list of the sockets found in the volume:

$ kubectl -n ns exec -it mail-0 -- /bin/bash
bash-5.1# find /var/spool/postfix/ -type s
/var/spool/postfix/private/scache
/var/spool/postfix/private/error
/var/spool/postfix/private/tlsmgr
/var/spool/postfix/private/retry
/var/spool/postfix/private/virtual
/var/spool/postfix/private/proxymap
/var/spool/postfix/private/local
/var/spool/postfix/private/relay
/var/spool/postfix/private/smtp
/var/spool/postfix/private/lmtp
/var/spool/postfix/private/discard
/var/spool/postfix/private/proxywrite
/var/spool/postfix/private/anvil
/var/spool/postfix/private/defer
/var/spool/postfix/private/rewrite
/var/spool/postfix/private/verify
/var/spool/postfix/private/trace
/var/spool/postfix/private/bounce
/var/spool/postfix/public/pickup
/var/spool/postfix/public/qmgr
/var/spool/postfix/public/showq
/var/spool/postfix/public/cleanup
/var/spool/postfix/public/flush
/var/spool/postfix/public/postlog

[bokysan]

According to postfix documentation (emphasis mine):

Note that a chrooted daemon resolves all filenames relative to the Postfix queue directory (/var/spool/postfix). For successful use of a chroot jail, most UNIX systems require you to bring in some files or device nodes. The examples/chroot-setup directory in the source code distribution has a collection of scripts that help you set up Postfix chroot environments on different operating systems.

I will update the next version of helm chart to map /var/spool/postfix/private and /var/spool/postfix/public into tmpDir -- hopefully this will do the trick.