How to make an online database standby?

496 views
Skip to first unread message

ran...@sanovi.com

unread,
Apr 13, 2009, 8:49:58 AM4/13/09
to
I have a primary database that is online and a secondary database on a
different Syb server that is "online for standby_access". I am able to
dump logs from primary, copy to secondary and apply them on the
secondary db (using load transaction).

I would like to reverse the process. That is, make the primary as
standby and the secondary as online. Logs should be able to be dumped
at secondary, copied to primary and applied at primary using load
transaction.

For this, I need a way to make the primary DB which is online to
switch to standby AND also be apply to accept "load transaction". (To
make the secondary DB online from standby, is a simple "online
database" command).

Can you help? Thanks in advance.
Regards,
Ranjit

Bret_Halford

unread,
Apr 13, 2009, 12:40:28 PM4/13/09
to

Easy enough. What you would do is (ideally during down time, if there
is activity, you will lose whatever
transactions occur after the quiescent point found in step b)

a) dump primary
b) after some activity in primary (even fake activity, like creating a
table and inserting a few thousand rows),
dump tran on primary for standby access
c) load the dump of primary back into primary
d) load the tran dump of primary back into primary
e) online primary for standby_access
f) load the dump of primary into secondary
g) load the tran dump into secondary
h) online secondary
i) begin using secondary for the actual work.

ran...@sanovi.com

unread,
Apr 14, 2009, 12:58:03 AM4/14/09
to
Bert,
Can I do this without the full database dump? That is, avoid the "dump
primary" (and also the "load" step)?

When a customer wants to do the above (as part of a weekend drill) on
a huge database (10-20GB) it is going to take a long time to do the
full database dump and full database restore.

I tested this a year ago very similar to your steps and it works.
However, I want to avoid the full dump/load.

(In MSSQL, one can simply do "restore logs from .... with standby ..."
to make the primary which is online to switch to standby mode.)

Regards,
Ranjit

ran...@sanovi.com

unread,
Apr 18, 2009, 5:57:23 AM4/18/09
to

> (In MSSQL, one can simply do "restore logs from .... with standby ..."
> to make the primary which is online to switch to standby mode.)
>
> Regards,
> Ranjit

Any possibility of doing this? In MSSQL you can dump a trans log at
primary, then LOAD the same trans log at same primary to make it the
standby. Possibly the same will work for Sybase?

kande...@gmail.com

unread,
Apr 27, 2016, 5:33:18 AM4/27/16
to
Hi
Any one has solution for this. Any possibility of doing Switchover and Switchback without doing fullback and restore.
Reply all
Reply to author
Forward
0 new messages