Re: [GENERAL] Lag in asynchronous replication

On Thu, Mar 23, 2017 at 11:37 PM, Subhankar Chattopadhyay
<subho.atg@gmail.com> wrote:
> in case of automated failover i want to check if slave is lagging from
> master and only if it is in sync, i want to do failover. But I am working in
> a virtual cloud environment so by that time the master VM may not be
> available to me. How can i check the lag in that case ?

Is your environment switching dynamically to async if the lag is too
important? If not, once you have reached a sync state, the master
would wait for all transactions commits to complete on the slave, so
once the client has received a commit confirmation you have the
guarantee that the data is already flushed on the slave. In this case
you don't need to know what happens on the master.
--
Michael