[Dovecot] No failover from director to backend?

[Patrick Westenberg]

Hi,

no one here who is able to reply to my questions?

Regards
Patrick



Patrick Westenberg schrieb:
> Hi everyone,
>
> short version:
> Is there no built in failover mechanism for the director service to
> handle a backend failure?
>
> Long version:
> I have a frontend server running the director service and two backends.
> Due to maintenance I had to shut down one of the backends which caused
> connection errors for the users being directed to this backend.
>
> I was very surprised as I expected the director to redirect these users
> to the remaining backend.
>
> Am I wrong or is the director not working as expected?
>
> Regards
> Patrick
>
>
>
> # 2.1.6: /usr/local/etc/dovecot/dovecot.conf
> # OS: Linux 2.6.32-5-amd64 x86_64 Debian 6.0.5
> auth_mechanisms = plain login
> director_mail_servers = 172.17.1.1 172.17.1.2
> director_servers = 172.17.1.3 172.17.1.4
> lmtp_proxy = yes
> log_path = /var/log/dovecot.log
> managesieve_notify_capability = mailto
> managesieve_sieve_capability = fileinto reject envelope
> encoded-character vacation subaddress comparator-i;ascii-numeric
> relational regex imap4flags copy include variables body enotify
> environment mailbox date ihave
> protocols = imap pop3 lmtp sieve
> service auth {
>    unix_listener /var/spool/postfix/private/auth {
>      group = postfix
>      mode = 0666
>      user = postfix
>    }
>    unix_listener auth-userdb {
>      user = dovecot
>    }
> }
> service director {
>    fifo_listener login/proxy-notify {
>      mode = 0666
>    }
>    inet_listener {
>      address = 172.17.1.3
>      port = 9090
>    }
>    unix_listener director-userdb {
>      mode = 0600
>    }
>    unix_listener login/director {
>      mode = 0666
>    }
> }
> service imap-login {
>    executable = imap-login director
> }
> service lmtp {
>    inet_listener lmtp {
>      address = 172.17.1.3
>      port = 24
>    }
> }
> service managesieve-login {
>    executable = managesieve-login director
>    inet_listener sieve {
>      port = 4190
>    }
> }
> service pop3-login {
>    executable = pop3-login director
> }
> ssl_cert = </etc/ssl/certs/imap.xx.crt
> ssl_key = </etc/ssl/private/imap.xx.key
> protocol !smtp {
>    passdb {
>      args = proxy=y nopassword=y starttls=any-cert
>      driver = static
>    }
> }
> protocol smtp {
>    passdb {
>      args = /usr/local/etc/dovecot/dovecot-sql.conf.ext
>      driver = sql
>    }
>    userdb {
>      args = /usr/local/etc/dovecot/dovecot-sql.conf.ext
>      driver = sql
>    }
> }
> protocol lmtp {
>    auth_socket_path = director-userdb
> }