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+Timeouts
+========
+
+Dovecot has a lot of timeouts in various components. Most of them have
+hardcoded values, because there's normally no need to change them. Here are
+some of them listed:
+
+IMAP
+----
+
+ * Before login: CLIENT_LOGIN_TIMEOUT_MSECS = MASTER_LOGIN_TIMEOUT_SECS*1000 =
+   3 minutes (login-common/client-common.h and lib-master/master-interface.h)
+    * This may be shorter if all the available connections are in use (service
+      imap-login { client_limit * process_limit }). In that case the oldest
+      non-logged in connection is disconnected.
+ * After login: CLIENT_IDLE_TIMEOUT_MSECS = 30 minutes (minimum required by
+   IMAP RFC)
+    * If IDLE command is started, Dovecot never disconnects. Only if the
+      connection is lost there will be a disconnection. A dead connection is
+      detected by Dovecot periodically sending "I'm still here" notifications
+      to client (imap_idle_notify_interval setting - default every 2 minutes).
+       * IMAP clients are supposed to send something before 30 minutes are up,
+         but several clients don't do this. Some Outlook versions even stop
+         receiving new mails entirely until manual intervention if IMAP server
+         disconnects the client.
+ * Dovecot also disconnects an IMAP client that sends too many invalid
+   commands:
+    * Before login: Disconnect on 3rd invalid command (CLIENT_MAX_BAD_COMMANDS
+      in imap-login/client.c)
+    * After login: Disconnect on 20th invalid command (CLIENT_MAX_BAD_COMMANDS
+      in imap/imap-common.h)
+
+POP3
+----
+
+ * Before login: CLIENT_LOGIN_TIMEOUT_MSECS = MASTER_LOGIN_TIMEOUT_SECS*1000 =
+   3 minutes (common with IMAP code)
+    * This may be shorter if all the available connections are in use (service
+      imap-login { client_limit * process_limit }). In that case the oldest
+      non-logged in connection is disconnected.
+ * After login: CLIENT_IDLE_TIMEOUT_MSECS = 10 minutes
+ * Dovecot also disconnects an POP3 client that sends too many invalid
+   commands:
+    * Before login: Disconnect on 3rd invalid command in v2.2.16+, 11th on
+      earlier versions (CLIENT_MAX_BAD_COMMANDS in pop3-login/client.c)
+    * After login: Disconnect on 20th invalid command (CLIENT_MAX_BAD_COMMANDS
+      in pop3/pop3-client.c)
+
+IMAP & POP3 proxies
+-------------------
+
+ * Dovecot proxy handles IMAP and POP3 pre-login timeouts and invalid error
+   command handling the same as Dovecot backend. After login the proxy will
+   continue proxying until the client or the backend disconnects.
+ * Connect timeout to backend is PROXY_DEFAULT_TIMEOUT_MSECS = 30 secs by
+   default. Can be overridden by proxy_timeout passdb extra field.
+ * After connection has been established, there's still a login timeout
+   CLIENT_LOGIN_TIMEOUT_MSECS = MASTER_LOGIN_TIMEOUT_SECS*1000 = 3 minutes
+   (login-common/client-common.h and lib-master/master-interface.h)
+
+(This file was created from the wiki on 2019-06-19 12:42)