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HBase >> mail # dev >> Can master initialization be done after postStartMaster is called?

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Re: Can master initialization be done after postStartMaster is called?
Hi Ram,

The MasterObserver.postStartMaster() hook was added after we ran into
a case where we wanted a single initialization point as soon as the
active master was up for security implementation.  In AccessController
we use it to create the "_acl_" table if it doesn't exist.  So in this
case it made sense to wait until the active master was fully up.

This is admittedly a pretty specific case, so it may be worth
rethinking some things as we generalize it.  If you're looking to have
a coprocessor perform some setup work required _before_ the active
master is available, maybe we should also look at adding a
MasterObserver.preStartMaster() hook?

Can you describe more how you're looking at applying this so we can
all understand the interactions?


On Mon, Mar 19, 2012 at 6:05 AM, Ramkrishna.S.Vasudevan
> Hi devs
> Currently we set HMaster initialized=true before calling postStartMaster.
> But if thro coprocessor we add some more code for some additional
> initialization or some cleanup work the master gets initialized even before
> that?
> Can we initialize the master after postStartMaster?  If it is ok I can file
> a JIRA for the same?
> Regards
> Ram