We have configured Dataguard in our environment, now looking forward for broker. But we have some queries.
1- What happens if Primary goes down (failover or switchover)?
2- If failover occurs, do we have to go back manually when primary is available?
3- If standby goes down, how'd broker reacts?
4- If network goes down (because of any reason) for some time, observer cant find primary and standby both, how'd it reacts then?
Please assist me with your advise.
Thanks & Regards,
First of all - Data Guard Broker can run without FSFO option enabled and can be used for manual operations as well.
If you have FSFO enabled the followed actions will happen.
If primary goes down (server failure or shutdown abort) - observer will wait until threshold and will failover to standby and open it as primary
You can use reinstate database feature and convert old primary into new standby
If standby is down there is no action in FSFO configuration
That's depend on configuration. If primary will be isolated from observer and standby it will be shut down, if there will be no link between observer and databases but primary can talk to standby there will be no actions.
Hi Sharjeel Mojib,
1) If you configure FSFO, and if primary goes down, failover will happen. If FSFO is not configured, then manual failover should be performed
2) Yes, You need to reinstate so that old primary will act as standby since failover happened. When both primary and standby is in sync, you can do a switchover, to have the standby as primary again(which was already a primary)
3) If standby goes down, and if you check the broker configuration, it ll show the down status of standby database. primary database wont be affected
4) If observer goes down, FSFO cannot happen, No log shipping will happen
Hello Marcin & Pradeep,
Many thanks for your reply. Just one more question, extension of question 2.
I have broker+observer configured in my environment, FSFO occured. Later, primary comes back alive. Now what happens? Should I have to manually reinstate or the observer is capable of doing it automatically?
Thanks & Regards,
Let me put in a way whether i understand your question. So you have broker+observer configured in your environment. FSFO occurred which means your standby becomes primary and is up and running. Then after some time the real primary is alive and what will the observer will do here.? right.?,...
If my understanding is right, here is the answer,
i) When the old primary is alive, just bring it back to mount state. The observer will automatically reinstate( if its running) the database, bounce the old primary and synchronize with the new primary (which is your old standby database). But remember your old primary will be having standby role still...
After the above process,
ii) If you want your old primary again, we need to do manual switchover to get your old setup.
Hope it would've cleared you.!!