Upgrading Dovecot v2.1 to v2.2
==============================

v2.2 has a couple of changes to settings since v2.1:

 * doveadm_proxy_port setting renamed to doveadm_port (but the old exists still
   as an alias)
 * imapc_ssl_ca_dir and pop3c_ssl_ca_dir settings replaced by a common
   ssl_client_ca_dir

There are also some changes you should be aware of:

 * fts-solr no longer does "hard commits" to the Solr index for performance
   reasons. <You must do this manually once in a while> [Plugins.FTS.Solr.txt].

 * When creating home directories, the permissions are copied from the parent
   directory if it has setgid-bit set. For full details, see
   <SharedMailboxes.Permissions.txt>.
 * "doveadm auth" command was renamed to "doveadm auth test"
 * IMAP: ID command now advertises server name as Dovecot by default. It was
   already trivial to guess this from command replies.
 * LDA/LMTP: If saving a mail brings user from under quota to over quota, allow
   it based on quota_grace setting (default: 10% above quota limit).
 * pop3_lock_session=yes now uses a POP3-only dovecot-pop3-session.lock file
   instead of actually locking the mailbox (and causing IMAP/LDA/LMTP to wait
   for the POP3 session to close).
 * mail_shared_explicit_inbox setting's default switched to "no".
 * dsync isn't compatible with v2.1 protocol. (The new protocol will be
   compatible with future Dovecot versions.)
 * autocreate plugin is being deprecated and it will log warnings. Convert the
   configuration to <MailboxSettings.txt> instead.

Downgrading can be done fully safely to v2.1.16.

 * v2.1.16 adds support for "attribute changes", which are used by URLAUTH
   command and dsync with ACLs and/or Sieve scripts. If none of these features
   are used, you can downgrade safely to v2.1.11.
    * The error message for these attribute changes is: 'Log synchronization
      error at seq=..,offset=.. for .../dbox-Mails/dovecot.index: Unknown
      transaction record type 0x0'
 * v2.1.11 adds support for cache file changes. Older versions may think that
   the 'dovecot.index.cache' files are corrupted and complain about "Invalid
   magic in hole header".

(This file was created from the wiki on 2019-06-19 12:42)