Hello All,

We are struggling to find a solution to a problem we are encountering

with a load-balanced email setup. Currently, we have a Coyote loadbalancer, and 3 Postfix/Dovecot nodes that then get their information from a mysql database. The problem is that after a couple weeks, we start seeing NFS locking issues occur, which then takes email completely down, requiring a site visit to basically do an interactive mode reboot to shut off NFS so that we can remount the filesystem again. We have our mailstore on an Aberdeen NAS which is accessed over NFS v. 4.

Dovecot version 1.1.2

Here's the relevant mysql string:

grep -v '^ *\(#.*\)\?$' dovecot-mysql.conf driver = mysql connect = host=X.X.X.X dbname=Something user=Something password=Something password_query = SELECT username as user, password, concat('/NFS1MAILDIR/mailSysV2/', maildir) as userdb_home, concat('maildir:/NFS1MAILDIR/mailSysV2/', maildir) as userdb_mail, 143 as userdb_uid, 143 as userdb_gid, concat('*:bytes=', floor(quota*1024)) AS quota_rule FROM mailbox WHERE username = '%u' AND active = '1' user_query = SELECT concat('/NFS1MAILDIR/mailSysV2/', maildir) as home, concat('maildir:/NFS1MAILDIR/mailSysV2/', maildir) as mail, concat('maildir:/NFS1MAILDIR/mailSysV2/', maildir) as maildir, 143 AS uid, 143 AS gid, concat('*:bytes=', floor(quota*1024)) AS quota_rule FROM mailbox WHERE username = '%u' AND active = '1'

And here's what our configuration is on each of the nodes:

dovecot -n # 1.1.2: /usr/local/etc/dovecot.conf protocols: imap pop3 ssl_ca_file: /usr/local/etc/dovecot/certs/tdpserver.crt ssl_cert_file: /usr/local/etc/dovecot/certs/tdpserver.crt ssl_key_file: /usr/local/etc/dovecot/certs/tdpserver.key ssl_parameters_regenerate: 0 ssl_cipher_list: ALL:!LOW:!SSLv2 disable_plaintext_auth: no login_dir: /var/run/dovecot/login login_executable(default): /usr/local/libexec/dovecot/imap-login login_executable(imap): /usr/local/libexec/dovecot/imap-login login_executable(pop3): /usr/local/libexec/dovecot/pop3-login login_user: postfix login_greeting: Something witty here.. login_process_per_connection: no login_max_connections: 512 max_mail_processes: 2048 mail_max_userip_connections: 50 verbose_proctitle: yes first_valid_uid: 69 last_valid_uid: 500 first_valid_gid: 69 last_valid_gid: 500 mail_access_groups: postfix mail_privileged_group: postfix mail_location: mbox:/NFS1MAILDIR/mailSysV2/%d/%u:INDEX=/usr/local/mail/indexes/%d/%1n/%n mmap_disable: yes dotlock_use_excl: no mail_nfs_storage: yes mail_nfs_index: yes mail_executable(default): /usr/local/libexec/dovecot/imap mail_executable(imap): /usr/local/libexec/dovecot/imap mail_executable(pop3): /usr/local/libexec/dovecot/pop3 mail_plugins(default): quota imap_quota mail_plugins(imap): quota imap_quota mail_plugins(pop3): quota mail_plugin_dir(default): /usr/local/lib/dovecot/imap mail_plugin_dir(imap): /usr/local/lib/dovecot/imap mail_plugin_dir(pop3): /usr/local/lib/dovecot/pop3 imap_client_workarounds(default): delay-newmail netscape-eoh tb-extra-mailbox-sep imap_client_workarounds(imap): delay-newmail netscape-eoh tb-extra-mailbox-sep imap_client_workarounds(pop3): pop3_client_workarounds(default): pop3_client_workarounds(imap): pop3_client_workarounds(pop3): outlook-no-nuls oe-ns-eoh auth default: mechanisms: login plain user: dovecot passdb: driver: sql args: /usr/local/etc/dovecot-mysql.conf userdb: driver: sql args: /usr/local/etc/dovecot-mysql.conf socket: type: listen client: path: /var/spool/postfix/private/auth mode: 432 user: postfix group: postfix master: path: /var/run/dovecot/auth-master mode: 384 user: dovecot group: dovecot plugin: quota: dict:user::proxy::quota imap_quota: dict:user::proxy::quota quota_rule: *:storage=528576 dict: quota: mysql:/usr/local/etc/dovecot/dovecot-dict-quota.conf

Any help you can offer is greatly appreciated, as well as opinions on any other 'validated' postfix/dovecot email enterprise design solutions.

Thanks Very Much In Advance,

R.T