Hi,
I need to organise to patch an SQL 2008 R2 environment up to SP2 level. It is a 4 node active/active/active/active configuration, with 4 named instances. One of the named instances is a distributor, the rest are both publishers and subscriber
I understand that the 'method' of patching replicated servers is distributor -> publisher -> subscriber - however my main question in this scenario is around timeframes and affects on replication.
If I was to patch the distributor first, how long could I leave the distributor at a different version from the publisher and subscriber? I'm assuming for patching the distributor like a normal cluster patch installation I will need to patch and failover to each node in order to ensure they are all patched which I can do - can the distributor be 'left' for potentially a few days to a week on a different SP than the publishers/subscribers?
More than 1 of the named instances are a publisher and a subscriber as well, so would I need to patch all the publishers first, then the subscribers - or should I patch the whole lot (publishers and subscribers) at once? What is the risk of the publishers/subscribers being on different SP levels - is it only changes to the publication that could affect the replicated environment?
I'm pretty much after a solution with least downtime, and potentially a solution where the 'downtime' can be 'staged', as well as potentially the work so I am not patching for 24 hours straight!
Thanks!
Melissa