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--- docs:tips_n_tricks:dovecot.html [22.10.2017 23:11 CEST] – [Troubleshooting replication] peter
+++ docs:tips_n_tricks:dovecot.html [01.02.2019 13:36 CET] (current) – [Remediation] peter
@@ Line 5: / Line 5: @@
 According to [[http://wiki2.dovecot.org/MailLocation/mbox#dotlocks|wiki2.dovecot.org]] the problem is solved by removing the write persmissions to the group on ''/var/spool/mail///username//''.
-===== Troubleshooting replication =====
+===== Replication =====
+==== Troubleshooting ====
 **Note:** The locally running replicator allways pushes the local changes to the far side (provided it is running without the ''-R'' flag)
@@ Line 11: / Line 12: @@
   doveadm replicator status <username pattern>
 //<username pattern>// is something like ''*@example.com'', ''user@example.com'', ''u*'' or just ''*''
+Run
+  doveadm replicator status '*' | fgrep ' y'
+to find failing mailboxes.
 Times shown are the time passed since last fast/full sync.
@@ Line 17: / Line 24: @@
 Accepts a username pattern as well, but works without it.
-  doveadmin replicator replicate -f <username pattern>
+  doveadm replicator replicate -f <username pattern>
 triggers a new full sync. (Needs to be called twice sometimes?)
-:!: ''doveadm force-resync'' is not related to replication!
+<note tip>''doveadm force-resync'' is not related to replication!</note>
 Credits:
   * https://wiki.dovecot.org/Replication
-===== Monitoring Replication =====
-Maybe
+==== Deduplication ====
+Sometimes, root cause of replication troubles seem to be duplicated emails. Those might be cleaned up in mailboxes //INBOX// and //Spam// for account //user@example.com// by
+<code bash deduplicate.sh>
+while doveadm deduplicate -u user@example.com mailbox INBOX OR mailbox Spam
+do
+  fgrep -c Message-ID: example.com/user/mail/Spam xid.at/xen/mail/INBOX
+  echo "++++ `date` +++++"
+done
+</code>
+This will run forever ans should be stopped when numbers do not change any more.
+==== Monitoring ====
+//This solution is for nagios-like monitoring systems//
+This needs a //sudo// entry to allow //nagios// running ''doveadm'' as //dovecot//
+<file bash check_dovecot.sh>
+  #! /bin/sh
+  # LANG=C doveadm replicator status|fgrep "'failed'"
+  repl_n_wait_fail="`LANG=C sudo -u dovecot doveadm replicator status|sed -ne \"s/^Waiting 'failed' requests *\([0-9]\+\) *$/\1/pg\"`"
+  # LANG=C doveadm replicator status|fgrep "'failed'"
+  # echo "\"$repl_n_wait_fail\""
+  case "$repl_n_wait_fail" in
+  "0") echo "OK: doveadm replicator status: Waiting 'failed' requests $repl_n_wait_fail"
+       exit 0 ;;
+  "1") echo "WARN: doveadm replicator status: Waiting 'failed' requests $repl_n_wait_fail"
+       exit 1 ;;
+  *)   if [ "$repl_n_wait_fail" -gt 1 ]
+       then
+          echo "CRIT: doveadm replicator status: Waiting 'failed' requests $repl_n_wait_fail"
+          exit 2
+       fi ;;
+  esac
+  echo "UNKNOWN: Strange value in doveadm replicator status for  waiting 'failed' requests: $repl_n_wait_fail"
+  exit 3
+</file>
+{{tag>monitoring nagios}}
+{{entry>monitoring}}
+{{entry>nagios}}
+==== Remediation ====
+Most cases I observed replication failures could be remedied by forcing deduplication. To my experience, ''dovecot deduplicate'' had to be run several times until all duplicate emails were removed.
+  dovecot deduplicate -u <user> '*'
+Repeat until
-  if doveadm replicator status  | fgrep "Waiting 'failed' requests     0"
+<file bash>
-  then
+  grep -c '^Message-ID:' path/to/mailbox
-    echo "OK"
+  grep '^Message-ID:' path/to/mailbox | sort -u | wc -l
-  else
+</file>
-    echo "ALARM"
-  fi
+show the same number.
 ======  ======
 {{tag>imap email dovecot}}
 {{entry>imap}}
 {{entry>email}}
-{{entry>dovect}}
+{{entry>dovecot}}