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• Currently Monitoring of Slave by admin is not possible
• Monitoring events are not integrated with MS

FAQs

Q: How fast the fail over will happen if master goes down?

A: It is actually the piing time out which controls this factor. The mysql connector property that controls this is "loadBalancePingTimeout".
     Currently this property is not exposed through db.properties so it uses the default pint time out value which is 0(Mean no ping time out)

Q:  What Mysql DB Versions are supported when DB HA is enabled?

A: The RHEL/CentOS versions supported by the Current ACS versions will get mysql versions of 5.1.X. So by defualt DB HA is also supported for these mysql versions only.

Q: Asynchronous replication V/S Semi-Synchronous Replication which one to use?

A: As Semi-Synchronous replication is supported by 5.5+ on wards so currently we support only Asynchronous replication only.

Q: How much latency is expected in syncing up when DB-HA is enabled?

A: The Synchronization between 2 master nodes is immediate and latency is depending on the actual network latency between 2 master nodes

Q: What Network topologies(Same Zone, Multiple Zones) are suggested?

A: .As mentioned in previous question, as long as we make sure the network latency between 2 master nodes is as much less as possible we can use any topology.

Appendix

• What if I want to do a Manual Switch over from Master-1 to Master-2?
  • Put a 2 way replication as above and do not enable the db ha in db.properties. I.e put the value false against the following property in db.properties
    db.ha.enabled=false

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