Look into continuent.com solutions, specifically tungsten replicator. If you have a budget involved, enterprise version of tungsten replicator can do master-master and handle conflicts. The pricing is not outrageous either.
> -----Original Message----- > From: Marty Sweet [mailto:msweet....@gmail.com] > Sent: Tuesday, November 05, 2013 5:43 PM > To: users@cloudstack.apache.org > Subject: Re: Multi-master MySQL Setup > > The issue with plain MySQL replication (espically in master-master) is that a > failed query will stop replication. A good example of this is when an record > is > added onto each master at the same time (within a second), say a new > record which gets the same primary key and replication will stop, on both > hosts. That then leaves a split brain situation when you have one master > writing its own data and another writing to itself, all with identical primary > keys. Absolute nightmare. This can how ever be migrated with the methods > the OP mentioned (I assume - but don't have experience of). > > I don't think file curroption is much of an issue with DRDB, but you can only > have one host write to it at anyone time (limitation of file system used), > which makes the master-slave or master-backup setup ideal when coupled > with HA service management software such as Pacemaker. You then have > the database files in both places without the dreaded MySQL replication > stories. > > I think the main question lyes with if the cloud admin wants a simple > redundant setup or a load balanced service - it may also we worth writing > some documentation for this to help future installations, although they will > have to be detailed. > > I have never used Percona/MariaDB, does it resolve the master-master > issues I mentioned earlier? > > Marty > > On Tuesday, November 5, 2013, Adrian Lewis wrote: > > > Seems like the Percona solution also uses Galera for their > > multi-master cluster. Starting to wonder whether to go MariaDB-Galera > > now. Tempted just to leave it as master slave replicated on MySQL > > though. Scale really not an issue right now. Ho hum, fun to be had if I had > the time to play. > > > > Assuming no Galera (with either MySQL/Percona/MariaDB) and just using > > Centos version of MySQL - does anyone have any input as to whether to > > go for replicating between two hosts using DRBD vs native MySQL > replication? > > I get the impression that MySQL replication is an > > eventually-consistent near-realtime kind of replication whereas DRBD > > can be set to be completely synchronous replication. MySQL replication > > just seems a lot less fiddly than using DRBD and DRBD would replicate > > file corruption that MySQL replication would be largely safe from. > > > > -----Original Message----- > > From: Patrick Miller [mailto:patrick.mil...@sungard.com > > <javascript:;>] > > Sent: 05 November 2013 21:51 > > To: users@cloudstack.apache.org <javascript:;> > > Subject: Re: Multi-master MySQL Setup > > > > Take a look at the percona [1] implementation of mysql and there > > clustered version. > > Round robin reads and writes supported. > > > > 1] http://www.percona.com/ > > > > Patrick > > > > > > On Tue, Nov 5, 2013 at 9:55 AM, Adrian Lewis > > <adr...@alsiconsulting.co.uk <javascript:;>>wrote: > > > > > Hi Marty/Nux!, > > > > > > Thanks for the feedback - sounds like multi-master is not a good > > > thing then! Load will likely be very small for at least the next 6 > > > months but I figured that it was one of those things that could be > > > set easily now (still setting up) that I might appreciate later. > > > > > > Based on both your responses, I think I'll just leave it well alone! > > > Need to get to grips with pacemaker/corosync anyway for other > > > reasons so I'll just try that with either DRBD replication or MySQL > replication. > > > > > > Cheers, > > > > > > Adrian > > > > > > -----Original Message----- > > > From: Marty Sweet [mailto:msweet....@gmail.com <javascript:;>] > > > Sent: 05 November 2013 17:23 > > > To: users@cloudstack.apache.org <javascript:;> > > > Subject: Re: Multi-master MySQL Setup > > > > > > Others may have had more success with this but from experience of > > > MySQL in multi-master setups I would avoid this entirely. > > > > > > A common setup is using DRDB to provide a master/slave: > > > Management 1 (MySQL Master) w/ virtual IP Management 2 (MySQL > Slave) > > > > > > HA IP Address (for agents/services requiring DB write) which is > > > assigned to the master (using Pacemaker). > > > > > > You can then send web management client to the HA IP Address as well. > > > > > > It may be worth considering if you need load balancing, depending on > > > your setup - what loads are you experiencing? > > > > > > Marty > > > > > > > > > > > > On Tue, Nov 5, 2013 at 5:13 PM, Adrian Lewis > > > <adr...@alsiconsulting.co.uk <javascript:;>>wrote: > > > > > > > Hi All, > > > > > > > > > > > > > > > > Just wondering if anyone is using a MySQL multi-master > > > > configuration with auto_increment_offset (e.g.10) and > > > > auto_increment_increment (1 for server 1, 2 for server 2 etc)? > > > > Does it work? Does anyone know a reason why it doesn't or wouldn't > > > > work? Is there anything from an application point of view that > > > > could/would trip up CS if auto_increment values are set as more than > 1? > > > > > > > > > > > > > > > > Not planning on deploying multimaster just yet but if I at least > > > > start with an auto_increment of 10, I'd have the option of adding > > > > a second master later and being able to load-balance more effectively. > > > > > > > > > > > > > > > > Thanks in advance, > > > > > > > > > > > > > > > > Adrian > > > > > > > > > > > >
