I meant to write this almost a year ago, but then I was asked to take a look at high cluster service privileged time usage and realized I had forgotten! I guess better late than never? If you’re using WSFC integrated AGs (cluster_type = WSFC) then the cluster database is the location in which availability […]
Read Scale Availability Groups can be pretty useful in the right places and for the right things and were a latest feature update for AGs until Contained AGs came along in 2022. Read Scale AGs don’t integrate with clustering of any type and they behave somewhat as mirroring used to where there is no real […]
The first video olved stery! In this one we look at an FCI node that will not come online after patching. Issue Introduction This was an issue I almost forgot about, during the patching of an FCI to a new CU, the inactive server patches without an issue – all is well. Upon attempting a […]
Setup If you’re using availability groups with read-scale or linux (cluster type = None/External), you might want to watch the number of databases put into a single availability group. There seems to be an issue where having a very large number (~200) of databases in an AG works without issue, however going higher may result […]
I was recently asked a question, while fixing a cluster connectivity issue, about how the cluster resource dll knows on which port to connect to SQL Server. It’s not a very exciting answer, which is, “It doesn’t.”. After some days passed I was thinking about the question and answer as though the response I had […]
I’ve been asked this question a few times, so I feel it’s worth writing about, which is, “Are Distributed Network Names (DNN) supported for SQL Server?”. The short version is, it’s not supported. The long version is, it’s not supported, but if you’re using a vanilla AG (not distributed) and aren’t using things like replication […]
I won’t say I told you so… I will, however, point out common AG question #8… I’m not sure why so many of these are coming up lately, but I’ve not had to troubleshoot a few, and I think it’s worth documenting this behavior. Let’s say you have Windows cluster which might have FCI’s, AG’s, […]
Update 5/24/2022: I’ve updated the DMV to reflect the various node and witness dynamic settings with a new column at the end of the DMV called number_of_current_votes. This is only in 2022 and will not be backported. Background I’ve now run across a few different instances where the monitoring for quorum was done via this […]
