[Dovecot] Question about index reset in dovecot 2.0.15

[Maria Arrea]

I have seen some strange error log messages in our dovecot server (2.0.15, RHEL 5.7x64, mdbox+zlib, local storage, high load)

 Dec 14 22:01:27 buzon dovecot: imap(fmcarrasco): Error: /indices_dovecot/indices/07/47/fmcarrasco/mailboxes/INBOX/dovecot.index reset, view is now inconsistent
 Dec 14 22:00:27 buzon dovecot: imap(cfp): Error: /indices_dovecot/indices/16/58/cfp/mailboxes/Sent/dovecot.index reset, view is now inconsistent
 Dec 14 20:56:46 buzon dovecot: imap(rcam): Error: Corrupted index cache file /indices_dovecot/indices/03/6b/rcam/mailboxes/INBOX/dovecot.index.cache: Broken virtual size for mail UID 132197
 Dec 14 21:50:38 buzon dovecot: imap(cfp): Error: Recent flags state corrupted for mailbox INBOX

 I have been googling without luck, why does this happen? I have tried with doveadm force-resync, maybe this could solve this issues.

 doveconf -n output

 # 2.0.15: /etc/dovecot/dovecot.conf
 # OS: Linux 2.6.18-274.7.1.el5 x86_64 Red Hat Enterprise Linux Server release 5.7 (Tikanga) ext4
 auth_cache_negative_ttl = 10 secs
 auth_cache_size = 10 M
 auth_cache_ttl = 2 mins
 auth_master_user_separator = *
 auth_mechanisms = plain login
 auth_worker_max_count = 3500
 base_dir = /var/run/dovecot/
 default_client_limit = 5000
 default_process_limit = 6500
 disable_plaintext_auth = no
 imap_client_workarounds = tb-extra-mailbox-sep delay-newmail tb-lsub-flags
 lda_mailbox_autocreate = yes
 lda_mailbox_autosubscribe = yes
 mail_fsync = never
 mail_gid = entrega
 mail_home = /buzones/domain/%2.26Hn/%2.200Hn/%n/home_usuario/
 mail_location = mdbox:/buzones/domain/%2.26Hn/%2.200Hn/%n:INDEX=/indices_dovecot/indices/%2.26Hn/%2.200Hn/%n
 mail_max_userip_connections = 15000
 mail_plugins = " zlib acl quota autocreate"
 mail_uid = entrega
 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
 mdbox_rotate_interval = 1 days
 mdbox_rotate_size = 60 M
 passdb {
 args = /etc/dovecot/dovecot-ldap.conf
 driver = ldap
 }
 passdb {
 args = /etc/usuario_maestro.txt
 driver = passwd-file
 master = yes
 }
 passdb {
 args = /etc/dovecot/dovecot-ldap.conf
 driver = ldap
 }
 plugin {
 acl = vfile
 autocreate = SPAM
 autocreate2 = Sent
 autocreate3 = Drafts
 autocreate4 = Trash
 autosubscribe = SPAM
 autosubscribe2 = Sent
 autosubscribe3 = Drafts
 autosubscribe4 = Trash
 lda_mailbox_autosubscribe = yes
 quota = dict:Cuota de usuario::file:/buzones/cuotas/%n
 quota_rule2 = Trash:storage=+10%%
 quota_warning = storage=90%% aviso_cuota 90 %u
 sieve = /buzones/domain/%2.26Hn/%2.200Hn/%n/home_usuario/dovecot.sieve
 sieve_dir = /buzones/domain/%2.26Hn/%2.200Hn/%n/home_usuario/sieve/
 zlib_save = gz
 zlib_save_level = 9
 }
 pop3_no_flag_updates = yes
 protocols = pop3 imap sieve
 service anvil {
 client_limit = 25000
 }
 service auth {
 client_limit = 28000
 unix_listener auth-master {
 user = entrega
 }
 unix_listener auth-userdb {
 user = entrega
 }
 user = root
 }
 service aviso_cuota {
 executable = script /usr/local/bin/quota-warning.sh
 unix_listener aviso_cuota {
 mode = 0666
 }
 user = entrega
 }
 service imap-login {
 executable = /usr/libexec/dovecot/imap-login
 group = dovenull
 service_count = 0
 vsz_limit = 1 G
 }
 service imap {
 executable = /usr/libexec/dovecot/imap
 process_limit = 6000
 }
 service managesieve-login {
 executable = /usr/libexec/dovecot/managesieve-login
 inet_listener sieve {
 port = 2000
 }
 process_limit = 2000
 vsz_limit = 1 G
 }
 service managesieve {
 executable = /usr/libexec/dovecot/managesieve
 process_limit = 5000
 }
 service pop3-login {
 executable = /usr/libexec/dovecot/pop3-login
 process_limit = 4000
 service_count = 0
 vsz_limit = 1 G
 }
 service pop3 {
 executable = /usr/libexec/dovecot/pop3
 process_limit = 4000
 }
 ssl_ca = </etc/pki/generico/cacert.crt.pem
 ssl_cert = </etc/pki/generico/wildcard-us_es.crt
 ssl_key = </etc/pki/generico/wildcard-key.pem
 userdb {
 args = /etc/dovecot/dovecot-ldap.conf
 driver = ldap
 }
 userdb {
 args = /etc/dovecot/dovecot-ldap-userdb.conf
 driver = ldap
 }
 verbose_proctitle = yes
 protocol sieve {
 managesieve_implementation_string = dovecot
 managesieve_logout_format = bytes=%i/%o
 managesieve_max_line_length = 65536
 }
 protocol lda {
 hostname = domain
 info_log_path =
 log_path =
 mail_fsync = optimized
 mail_plugins = sieve zlib quota
 postmaster_address = evcorreo at domain
 syslog_facility = mail
 }
 protocol imap {
 mail_plugins = zlib autocreate quota imap_quota
 }
 protocol pop3 {
 mail_plugins = zlib
 pop3_enable_last = yes
 pop3_uidl_format = %g
 }


 Regards

 Maria