August 12, 2014 at 5:55 am
Hi,
Since I don't have a testing environment, I am seeking help on this.
In a 2-node SQL Cluster, if Node-1 is on SQL 2008 SP3 and Node-2 is running on SP1 will instance gets failover irrepective of service pack level?
Thank you.
August 12, 2014 at 6:22 am
vsamantha35 (8/12/2014)
Hi,Since I don't have a testing environment, I am seeking help on this.
In a 2-node SQL Cluster, if Node-1 is on SQL 2008 SP3 and Node-2 is running on SP1 will instance gets failover irrepective of service pack level?
Thank you.
Yes, it will also perform a downgrade of the SQL server instance. For this reason follow the MS patch guide here
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"Ya can't make an omelette without breaking just a few eggs" 😉
August 12, 2014 at 6:31 am
Thank you Sir.
August 13, 2014 at 11:19 am
The way I have applied SPs and CUs is apply it to the inactive node, restart that node. Once you ahve time for an outage fail SQL Server over to the newly updated Node... make sure SQL Server is upgraded and is functional. Then apply the SP or CU to that now inactive node. Restart it. Fail SQL Server back over to that node to make sure it is all functional.
I have never removed a node from the cluster Admin.
August 13, 2014 at 12:07 pm
The Microsoft recommendation removes any unpatched nodes from the possible owners of the VNN resource to prevent a failover causing a downgrade.
In most scenarios not all nodes are patched in one sitting.
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"Ya can't make an omelette without breaking just a few eggs" 😉
September 28, 2017 at 1:09 pm
Sorry for this act of thread necromancy. And thread-jacking, I guess. Yay for first posts!
Perry, if you are still out there, would you be able to point me to any documentation that confirms the downgrade will occur? I'm trying to confirm that if we apply a service pack to an inactive node then failover to it, we can safely failback to an unpatched node if things go south.
I'm having trouble finding confirmation one way or the other online. The link you provided mentions possible data corruption by having mixed versions as possible owners. This makes me think I want to avoid the scenario? I guess we could try to uninstall the service pack instead, although the Microsoft rep we had on site a while back told us uninstalling SQL Server service packs was something we really wanted to avoid. Anecdotes among the team seem to support that view.
September 29, 2017 at 8:50 am
vsamantha35 - Tuesday, August 12, 2014 5:55 AMHi,Since I don't have a testing environment, I am seeking help on this.In a 2-node SQL Cluster, if Node-1 is on SQL 2008 SP3 and Node-2 is running on SP1 will instance gets failover irrepective of service pack level?Thank you.
I suppose the cluster setup would have failed first-up , had there been any incompatibility / disagreements between the two instances.
October 2, 2017 at 8:39 am
Mike W aka Mike W - Thursday, September 28, 2017 1:09 PMSorry for this act of thread necromancy. And thread-jacking, I guess. Yay for first posts!Perry, if you are still out there, would you be able to point me to any documentation that confirms the downgrade will occur? I'm trying to confirm that if we apply a service pack to an inactive node then failover to it, we can safely failback to an unpatched node if things go south.
I'm having trouble finding confirmation one way or the other online. The link you provided mentions possible data corruption by having mixed versions as possible owners. This makes me think I want to avoid the scenario? I guess we could try to uninstall the service pack instead, although the Microsoft rep we had on site a while back told us uninstalling SQL Server service packs was something we really wanted to avoid. Anecdotes among the team seem to support that view.
The link i posted details how to carry out a rolling upgrade. It informs you of how to downgrade\rollback, by uninstalling the update and then moving the instance to a downgraded node. Check the logs on your instance when you fail back to a lower level version you'll see the downgrade recorded there
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"Ya can't make an omelette without breaking just a few eggs" 😉
October 2, 2017 at 8:57 am
This was removed by the editor as SPAM
October 2, 2017 at 9:03 am
I think you have to be careful here about failing to a lower SP version. Some SP versions will rev the database level, which means a previous version of SQL can't read the files. You'll have issues.
You should apply an SP to a node, fail over, and then apply to the first (now secondary) node. If you cannot apply patches to a node, then you want to remove the SP patch, but if you've already moved the dbs to this node, SQL doesn't downgrade the database. Most Service Packs don't rev the internal database revision, but some do.
Perry, I'm not sure what you see in that kb, but am I missing something. Doesn't appear to say SQL will downgrade. The admin needs to downgrade before running SQL Server on the node that's been updated. IIRC, SQL Server 2008 SP2 introduced the 15k partition limit, which rev'd the database internal version level, so SP3 shouldn't be able to go to SP1.
October 20, 2017 at 12:30 pm
Sorry, got sidetracked!
Thanks Perry, I somehow missed that entire section on removing patches!
Thanks for your reply too Steve! I had not considered what might happen if an SP introduced a new feature. Aaron Bertrand has a write up about moving databases between SP's and mentions the SP you bring up. According to his test, you can downgrade a 2008 database from SP2 to SP1 provided you do not enable the new partition limit on any databases. Perhaps this will hold true for failover downgrades as well?
Still, his blog mentions a number of caveats and seems to suggest caution. Sounds like the message here is to test it first (of course!), but I unfortunately do not have an environment to do so on. Thanks for your input everyone!
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