Thank you very much for this information. This sounds like a very good strategy. I think I
will try switching some slaves from one relay to another to familiarize myself and get
practice and them do it to deploy a new master.
Again, thank you very much.
> El Jan 18, 2014, a las 2:00 AM, Manuel Arostegui <manuel@stripped>
> 2014/1/17 Richard Reina <gatorreina@stripped>
>> I have 3 relay MySQL database servers on my small office LAN backing up a
>> master and 3 more machines backing up each relay (1 each). They are all
>> replicating all databases and all tables. The master although running fine
>> is almost eight years old. I'm thinking it's probably time to make one of
>> the relays the master, but I've never done this before.
>> I want the new master to have the IP address of the old master 192.168.0.1
>> . To make the change I was going to take the master off the LAN and
>> shutdown mysql on all the machines, change the IP address on the chosen
>> relay to that of the master 192.168.0.1, then restart mysql on all the
>> machines. I always refer to the machines by their IP addresses and never by
>> their hostnames. Once I successfully make the change I was planning on
>> making the old master a relay since it is still working fine.
>> Will this plan work ok? Is there a better or easier way?
> If the three machines are sync'ed and have consistent data I don't see the need of
> stopping MySQL:
> - Stop whatever writes to your current master
> - Once you are completely sure there are no writes in your current master, set it to
> read_only = ON
> - In the slave which will become the master, get the logfile and current position
> with: show master status;
> - Set the new IP in the new master
> Using the position taken in the new master go to the slaves machines and:
> stop slave; change master to master_host='IP',
> master_log_file='whatever_file_name_you_got', master_log_pos=whatever_number_you_got,
> master_password='replication_or_whatever_you_have'; start slave;
> - Set read_only = OFF in your new master
> - Start your application so you can start getting writes again.
> As soon as you get writes if you do a "show master status;" in the new master you
> should see the position going forward.
> I see that faster than any other thing.
> Hope this helps