Thanks for the suggestions!
~$ telnet server1.teststable.simplyspamfree.com 143
Try 127.0.0.1 vs ::1
I should have thought of that :) Indeed, ::1 works fine, so it is not IPv6, it is external IPv6.
Proxy/firewall/antivirus/etc in the middle?
I don't think so.
If none of that is helpful, set auth_debug_passwords=yes and see the logs.
With the successful connection to ::1 I get:
""" 2010-11-02 02:43:29 auth(default): Info: new auth connection: pid=28423 2010-11-02 02:43:35 auth(default): Info: client in: AUTH 1 PLAIN service=imap secured lip=::1 rip=::1 lport=143 rport=42445 resp=AHRyYWluaW5nAGZsaXRrWGw3bHgyQWdQemc= 2010-11-02 02:43:35 auth-worker(default): Info: sql(training,::1): query: SELECT DISTINCT "training" AS user, password FROM dovecot WHERE account="testing override"; 2010-11-02 02:43:35 auth-worker(default): Info: sql(training,::1): Password mismatch 2010-11-02 02:43:35 auth-worker(default): Error: ssha256_verify(training): SSHA256 password too short 2010-11-02 02:43:35 auth-worker(default): Warning: Invalid OTP data in passdb 2010-11-02 02:43:35 auth-worker(default): Warning: Invalid OTP data in passdb 2010-11-02 02:43:35 auth-worker(default): Info: sql(training,::1): PLAIN-MD5(XXXXXXXX) != '6e202e30677971ea4ebe5e562ae5c195' 2010-11-02 02:43:35 auth-worker(default): Info: sql(training,::1): query: SELECT DISTINCT "training" AS user, password FROM dovecot WHERE account=LOWER("training"); 2010-11-02 02:43:35 auth(default): Info: client out: OK 1 user=training 2010-11-02 02:43:35 auth(default): Info: master in: REQUEST 2 28374 1 2010-11-02 02:43:35 auth-worker(default): Info: sql(training,::1): SELECT DISTINCT CONCAT_WS("/", "/var/mail", LEFT(account, 1), LEFT(account, 2), LOWER(account)) AS home, CONCAT_WS("/", "maildir:/var/mail", LEFT(account, 1),LEFT(account, 2), LOWER(account)) AS mail, 1001 AS uid, 8 AS gid, CONCAT("*:storage=", FLOOR(quota)) AS quota_rule FROM dovecot WHERE account=LOWER("training") 2010-11-02 02:43:35 auth(default): Info: master out: USER 2 training home=/var/mail/t/tr/training mail=maildir:/var/mail/t/tr/training uid=1001 gid=8 quota_rule=*:storage=10245120 2010-11-02 02:43:35 imap-login: Info: Login: user=<training>, method=PLAIN, rip=::1, lip=::1, secured 2010-11-02 02:43:38 IMAP(training): Info: Disconnected: Logged out bytes=8/334 """
With the external connection to IPv6 nothing at all gets written to the Dovecot log. (External IPv4 works fine). If I do an SSL connection I get only this for external IPv6:
""" 2010-11-02 02:51:38 imap-login: Info: Disconnected (no auth attempts): rip=178.63.10.79, lip=188.40.178.56 2010-11-02 02:51:38 auth(default): Info: new auth connection: pid=28726 """
I'm afraid that still leaves me stumped. Any further suggestions?
Thanks, Tony