Originally Posted by erosbk
I have a multiserver setup, do I have to update first master or slaves?
Thanks for all the work guys!
Thats not trivial to answer, but I would update the master first.
A short explanation of the pros and cons of the update order and what could happen:
1) Update slaves first:
pro: As we normally add only fields to the database when applying a update and the fields are downwards compatible, changes wriiten from a older master to a newer slave should work.
con: If a new field is added where the slave needs to write data to the master and the slave tries to configure its permissions for this database field in the amster server, mysql will report a error and dont change the field permissions as the field does not exist yet.
2) Updates master first.
pro: the con of 19 can not happen.
con: changes done in the master until the slaves are updated might fail in the way that you get a replication errot. You should see then a error message in the ispconfig monitor system log. But thats easy to handle as you just have to click on the delete button in the error list to report that the error has been solved and ispconfig will try to do the replication of the failed record again.