Hello,
On Fri, 6 Oct 2017, Jozsef Kadlecsik wrote:
We upgraded one of our dovecot servers to debian stretch with dovecot 2.2.27 and since then one of our users has been experiencing random IMAP failures.
We enabled raw logging at the server side and it shows normal IMAP commands/responses:
1507292522.222427 * 6 FETCH (FLAGS () BODYSTRUCTURE ("text" "plain" ("charset" "us-ascii") NIL NIL "7bit" 4645 112 NIL NIL NIL NIL)) 1507292522.222653 00000011 OK Fetch completed (0.006 + 0.000 secs).
On the client side the user runs alpine and the corresponding debug lines:
IMAP DEBUG 14:22:02.216167: 00000011 FETCH 6 (BODYSTRUCTURE FLAGS)
14:22:02.217396 IMAP 14:22:02 10/6 mm_notify bye: {[127.0.0.1]:1555/imap/user="ha4aa"}INBOX: [CLOSED] IMAP connection broken (server response)
14:22:02.217471 IMAP 14:22:02 10/6 mm_log error: [CLOSED] IMAP connection broken (server response)
The "[127.0.0.1]:1555/imap/user="ha4aa" part in the log comes from an socat inserted between the client and the server to check independently the imap session. According to socat, the server response didn't reach the client!:
00000010 OK Fetch completed (0.005 + 0.000 secs).\r
2017/10/06 14:22:02.216299 length=40 from=845 to=884 00000011 FETCH 6 (BODYSTRUCTURE FLAGS)\r
and here ends the socat log.
The date of the last rawlog line corresponds to an ssl debug log of dovecot (from the last run):
Oct 20 18:50:05 mail2 dovecot: imap-login: Debug: SSL error: SSL_read() failed: error:140E0197:SSL routines:SSL_shutdown:shutdown while in init
I added the patch "openssl: Clear error queue after an incomplete SSL_shutdown", recompiled the package but it did not help.
Any help is highly welcomed!
Best regards, Jozsef
E-mail : kadlecsik.jozsef@wigner.mta.hu PGP key: http://www.kfki.hu/~kadlec/pgp_public_key.txt Address: Wigner Research Centre for Physics, Hungarian Academy of Sciences H-1525 Budapest 114, POB. 49, Hungary