When you fail over you have to open resetlogs. Switchover is a clean
switch, no resetlogs required.
On Thu, Jun 4, 2015 at 4:23 PM, max scalf <oracle.blog3@xxxxxxxxx> wrote:
okay make sense, one question when we FAILOVER why does the DBID changes
?? or is it also doing a resetlogs ?
On Thu, Jun 4, 2015 at 3:16 PM, Andrew Kerber <andrew.kerber@xxxxxxxxx>
wrote:
I am referring to the original primary in that case. As I understand it,
with flashback turned on, the reinstate command in dgmgrl will flash the
original primary back to an earlier point, then apply the logs from the
current primary to put the original primary into standby mode, ready for a
clean switchover.
On Thu, Jun 4, 2015 at 2:57 PM, max scalf <oracle.blog3@xxxxxxxxx> wrote:
Thanks Andrew, i did not realized that. Also looks like the log seq#
resets back to 1 on the new primary(DC-B).
Also when you mentioned "flashback allows you to flash the PRIMARY back
to an instance before the divergence and start the apply"...are you talking
in this situation the CURRENT PRIMARY (DC-B) which has been up for 4 hours
now will be flashed back to noon followed by rollforward ?? Wouldnt that
be on the standby ??
On Thu, Jun 4, 2015 at 2:40 PM, Andrew Kerber <andrew.kerber@xxxxxxxxx>
wrote:
Nope. At that point, if you have a done failover, the dbid on the
standby is different from the primary. In effect, at that point its a
completely different database. Flashback allows you to flash the primary
back to an instant before the divergence, and you can apply the logs from
that point, but you have to flash it back for that to work.
On Thu, Jun 4, 2015 at 1:29 PM, max scalf <oracle.blog3@xxxxxxxxx>
wrote:
Hello list,
I am trying to get my head around reinstating a database in dataguard
scenario, i am very new to DG and hence having issue trying to understand
this.
So lets say i have datacenter DC-A and Datacenter DC-B and i have
setup DG between the two(Max Perf mode). Now lets say DC-A goes down
unexpectedly (and lets assume that DC-A will come back up in 3-4 hours as
know we know whats wrong and network team is trying to fix that), also
lets
assume this happened at noon and my log seq# at primary was 300.
Obviously
in the mean time i am going to FAILOVER to standby in DC-B and everything
is happy. Time passes along and now its 4PM and lets assume now my
primary
in DC-B is at log seq# 320.
Now at 4PM, my DC-A is back and i want to bring the former primary
into standby mode. I can either use flashback(if enabled earlier) or
recreate my standby again to do that. My question is, instead of using
flashback or rman to recreate my standby(DC-A), cant i just mount my
database in DC-A, copy over logs from seq# 300-320 from DC-B on to DC-A,
roll forward DC-A and then start my redo apply instead of recreating
standby(or using flashback)??
I guess in short i am asking y do we have to use flashback or use
RMAN/re-create to reinstate my standby database? is there any other way
to
reinstate my database(fromer primary).
--
Andrew W. Kerber
'If at first you dont succeed, dont take up skydiving.'
--
Andrew W. Kerber
'If at first you dont succeed, dont take up skydiving.'
