sarma pisapati

Any service pack upgrade to the SQL server cluster will
halt the SQL resource group on the participating nodes.
This is not acceptable for today's need for five nines. We
should minimize the impact on availability due to patches.
For example, if there is just code updates (where code can
reside on the local drive), why don't we upgrade node by
node to make the SQL resource group highly available?

Comments are most welcome.

SP

mike epprecht [sql server mvp]

I see that one of the issues is that certain scripts run during a SP
installation process. They need to run against the master, model, msdb and
distribution databases so in effect, the active node needs to be upgraded,
resulting in it being unavailable.

SQL SP's are released on a near 9 month cycle whilst Windows gets it more
often, and with all the Windows patches, it is monthly.

I see no issue with having a SQL server offline for 3-5 minutes every 9
months. I think it is acceptable, and based on the complexity of SQL, I
think it is good. I'd hate to have a cluster go south because one node was
not on the same version/revision number as the rest.

You don't get to five nine's with just a 2 or 4-node cluster, you start to
talk multiple clusters etc.

Regards
--
--------------------------------
Mike Epprecht, Microsoft SQL Server MVP
Epprecht Consulting (PTY) LTD
Johannesburg, South Africa
Mobile: +27-82-552-0268
IM: mike@NOSPAMepprecht.net

Specialist SQL Server Solutions and Consulting

sarma pisapati

Does it happen with hot-fixes too? With the frequency of
security patches, I am glad that there is no impact to OS.

BTW, do you recommend SQL software to go on to shared
disks?

during a SP

master, model, msdb and

needs to be upgraded,

Windows gets it more

minutes every 9

complexity of SQL, I

because one node was

cluster, you start to

mike epprecht [sql server mvp]

SQL Server binaries must always be installed on the local disks of each
cluster node.

SQL hotfixes are usually applied manually (read as: re-name a file and copy
the newer version to the same location etc), but it is a real bad idea to
have different nodes on different versions. You never know what side effects
you may have. Some hotfixes require you to run scripts, so it still affects
the uptime of the cluster.

Regards
--
--------------------------------
Mike Epprecht, Microsoft SQL Server MVP
Epprecht Consulting (PTY) LTD
Johannesburg, South Africa
Mobile: +27-82-552-0268
IM: mike@NOSPAMepprecht.net

Specialist SQL Server Solutions and Consulting

sarma pisapati

I fully agree with you on maintaining single version
across all nodes. My question is totally related to High-
Availability. I am going to run a 24x7x365 app. I want to
minimize the downtime whereever it is feasible. if hot-
fixes can be applied in a sequence so that atleast one
node will be available for SQL services, I would love to
implement in the support process.

disks of each

name a file and copy

real bad idea to

know what side effects

so it still affects