dovecot - May 2021 - NFS Locking Question

Hi!

I'm hoping to get some clarification on NFS locking before deploying a new
setup.

We have a single exim server that delivers mail to mbox files in /var/mail. We
have a separate
server running dovecot that reads mail from these mbox files. So only one exim
server and one
dovecot server, but they're separate VMs and handle locking with dotlocks.

I was noticing frequent mbox file corruption. I then set "mail_nfs_storage
= yes", and have seen no
mbox corruption since. However, I'm now seeing messages like this in the
logs for every read...

Error: nfs_flush_fcntl: fcntl(/var/mail/username, F_RDLCK) failed: Bad file
descriptor

Is there a configuration change that needs to be made on the dovecot or the NFS
servers, or are these
messages harmless.

Thanks!
ZZ

On 25/05/2021 16:46, Zane Zak wrote:
> We have a single exim server that delivers mail to mbox files in /var/mail.
We have a separate
> server running dovecot that reads mail from these mbox files.
...
> Is there a configuration change that needs to be made on the dovecot
I don't know about the NFS problem but change your configuration to use 
LMTP delivery.

https://wiki.dovecot.org/LMTP/Exim

Plus there are plenty of reasons to not use mbox.