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 <plugin-fts_solr_soft_commits>.

  • When creating home directories, the permissions are copied from the parent directory if it has setgid-bit set. For full details, see https://wiki.dovecot.org/SharedMailboxes/Permissions.

  • 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 Mailbox settings 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”.