Most changes in Enswitch 4.2 purely add functionality, but some change or remove functionality. Here is a list of such changes. If any of these adversely affect you, please contact support as soon as possible.

• MySQL replication with statement based or mixed replication is no longer supported. Replication must be changed to row based replication.
• Asterisk voicemail is deprecated. Please switch to Enswitch voicemail by setting the "Voicemail uses Asterisk" setting to no.
• The names of executables in /opt/enswitch/current/bin and /opt/enswitch/current/sbin have changed. Please update any scripts, cron entries, etc, that invoke them.
• As in version 4.1, the behavior of the exec() subroutine in lib/Database.pm is to NOT die() when there is an SQL error. This will allow the execution of the script calling sql() or any other database-altering subroutine from lib/Database.pm to continue execution. To revert to the previous behavior where the script would die() in case of an SQL error, the global configuration variable "Die on SQL errors" has been introduced.
• As usual, some JSON API functions have changed. If using the JSON API, these should be reviewed before upgrading.