Dsync and network issues

[Danilo G. Baio via dovecot]

Hi.

Our scenario:
    dovecot-2.3.4.1
    Two FreeBSD servers, A (master) and B (slave).
    replication_max_conns = 10
    doveadm_port = 60025

All mails are received on server A and replicated to server B.

Sometimes we get these messages on server B:

Feb 18 08:27:35 dsync-server(XX@XX): Error: client_connection_tcp_free:
close((&conn->fd)) @ client-connection-tcp.c:632 failed (fd=15): Connection
reset by peer
Feb 18 08:28:00 dsync-server(XZ@XZ): Error: client_connection_tcp_free:
close((&conn->fd)) @ client-connection-tcp.c:632 failed (fd=15): Connection
reset by peer
Feb 18 08:33:14 dsync-server(XY@XY): Error: client_connection_tcp_free:
close((&conn->fd)) @ client-connection-tcp.c:632 failed (fd=15): Connection
reset by peer
Feb 18 08:44:07 dsync-server(XW@XW): Error: client_connection_tcp_free:
close((&conn->fd)) @ client-connection-tcp.c:632 failed (fd=15): Connection
reset by peer

It happens sometimes (usually early morning) when users are syncing their
mailboxes.

Is there a way to debug this and find what is happening?

Thanks for your time.
-- 
Danilo G. Baio