<html><head></head><body>I have the same Problem here.<br>All systems are running Debian 9 amd64.<br><br>My dovecot director servers are running 2.3.8, but the Mailbox Servers having sync / replication problems with 2.3.8. So i have downgraded the Mailbox Servers to 2.3.7 and now everything works fine again...<br><br><div class="gmail_quote">Am 18. Oktober 2019 13:52:37 MESZ schrieb Carsten Rosenberg via dovecot <dovecot@dovecot.org>:<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
<pre class="k9mail">Hi,<br><br>some of our customers have discovered a replication issue after<br>upgraded from 2.3.7.2 to 2.3.8.<br><br>Running 2.3.8 several replication connections are hanging until defined<br>timeout. So after some seconds there are $replication_max_conns hanging<br>connections.<br>Other replications are running fast and successful.<br><br>Also running a doveadm sync tcp:... is working fine for all users.<br><br>I can't see exactly, but I haven't seen mailboxes timeouting again and<br>again. So I would assume it's not related to the mailbox.<br><br>From the logs:<br><br>server1:<br>Oct 16 08:29:25 server1 dovecot[5715]:<br>dsync-local(username1@domain.com)<FXnVDW22pl0tGAAA1cwDxA>: Error:<br>dsync(172.16.0.1): I/O has stalled, no activity for 600 seconds (version<br>not received)<br>Oct 16 08:29:25 server1 dovecot[5715]:<br>dsync-local(username1@domain.com)<FXnVDW22pl0tGAAA1cwDxA>: Error:<br>Timeout during state=master_recv_handshake<br><br>server2:<br><br>Oct 16 08:29:25 server2 dovecot[8113]: doveadm: Error: read(server1)<br>failed: EOF (last sent=handshake, last recv=handshake)<br><br>There aren't any additional logs regarding the replication.<br><br>I have tried increasing vsz_limit or reducing replication_max_conns.<br>Nothing changed.<br><br>--<br><br>Both customers have 10k+ users. Currently I couldn't reproduce this on<br>smaller test systems.<br><br>Both installation were downgraded to 2.3.7.2 to fix the issue for now<br><br>--<br><br>I've attached a tcpdump showing the client showing the client stops<br>sending any data after the mailbox_guid table headers.<br><br><br><br>Any idea what could be wrong here or the debug this issue?<br><br>Thanks.<br><br>Carsten Rosenberg<br></pre></blockquote></div><br>-- <br>Diese Nachricht wurde von meinem Android-Gerät mit K-9 Mail gesendet.</body></html>