Load balancer for dovecot servers - Not able to send emails

[Alexander Dalloz]

Am 22.04.2020 um 15:12 schrieb Kishore Potnuru:
> Hi All,
> 
> I need your help on one of the issue in Dovecot.

Why do you send that request to me personally in Cc:?

> I have the dovecot version 2.0.9 installed on RHEL linux 6.10 version. It's
> a single/standalone Live server.
> 
> Now I have created another server with the same configuration for the
> resilince purpose. I also tested and I am able to send the emails to both
> of the dovecot servers separately/individually. They are working fine.
> 
> Now I have added those two servers under a F5 load balancer and created a
> FQDN (example: testing.test.com). I changed the rules to send the traffic
> to FQDN "testing.test.com", where it should redirect the email to one of
> those 2 servers.
> 
> When I sent the email to FQDN "testing.test.com", I am getting the below
> error.
> 
> pf1_inbd/smtp[30292]: 66A5F5F6: to=<xxxxx at yyy.com>,
> relay=testing.test.com[xxx.xxx.xxx.xxx]:25,
> delay=13, delays=0.09/0.08/13/0, dsn=4.4.2, status=deferred (lost
> connection with testing.test.com [xxx.xxx.xxx.xxx] while receiving the
> initial server greeting)

That's the MTA on port 25 not reacting as it should. That's no dovecot 
iisue.

> Could you please let me know how to fix this issue? It's a great help for
> me.
> 
> Thanks & Regards,
> Kishore Potnuru

Alexander