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SnapCenter on SQL cluster active-active

Hi,

   I have installed SnapCenter 4.2.0 agents in two node SQL Server cluster with active-active configuration. But SnapCenter only can access to the instances running in the node which own cluster name resource. Does anybody know how can I work with the instances on the secod cluster node?

8 REPLIES 8

Re: SnapCenter on SQL cluster active-active

Hi,

 

Interesting query, Is that not a normal behavior ?

 

SQL Cluster supports a Failover Clustering only where only one node is active at a certain point of time and next node takes up the work post a failover happens automatically/manually triggered.

 

Considering that , SnapCenter agent will only see the resources for the Node that is active.

 

Does SQL Server support 'true' Active/Active Clustering?
https://social.msdn.microsoft.com/Forums/sqlserver/en-US/a367a0cb-9231-42ae-9ddb-d59b9aa83ab9/does-sql-server-support-true-activeactive-clustering?for...


Could someone from SnapCreator team confirm this ?

 

Thanks!

 

Re: SnapCenter on SQL cluster active-active

When I say active/active I mean that each node runs different instances of SQL Server. For example:

 

  - Node 1 executes instances A and B
  - Node 2 executes instances C and D

 

SnapCenter can only access instances that run on the node that has the cluster name. If the cluster name is on node 1, SnapCenter only accesses instances A and B. If the cluster name is on node 2, SnapCenter only accesses instances C and D.

 

Re: SnapCenter on SQL cluster active-active

Thanks for clearing that for me, that makes sense when you say 'active/active'.

 

I guess, the question now is : Is it supported with SnapCenter ?

 

I will try to find this out.

 

Thanks!

Re: SnapCenter on SQL cluster active-active

Hi,

 

There is a reference of installing plug-in on SQL cluster.

 

Adding hosts and installing SnapCenter Plug-in for Microsoft Windows:
http://docs.netapp.com/ocsc-40/index.jsp?topic=%2Fcom.netapp.doc.ocsc-isg%2FGUID-8674BCB1-0CA6-4B2B-8D07-146E1AB9AE79.html

 

Installing plug-ins on a cluster: (I don't know if AlwaysOn means Active/Active)
If you install plug-ins on a cluster (WSFC, Oracle RAC, SQL Always OnAvailability Groups, or Exchange DAG), they are installed on all of the nodes of the cluster.


Could you ensure this:
SnapCenter depends on the proper configuration of the DNS. Therefore, the best practice is to enter the fully qualified domain name (FQDN). If you are adding a host using SnapCenter and it is part of a subdomain, you must provide the FQDN.

 

Thanks!

Re: SnapCenter on SQL cluster active-active

It is possible that the problem lies in the resolution names. We have a disjoint Windows namespace: the domain FQDN is "usc.es" but the servers FQDN is "server1.rpso.usc.es" being "rpso.usc.es", not a Windows subdomain , but a DNS zone.

SnapCenter doesn't understand that and insists on always resolving "server1.usc.es" so we have to fool it with a "hosts" file establishiong alias like "server1.usc.es".

 

But after installing the agents we find this problem.

 

Re: SnapCenter on SQL cluster active-active

Thanks for the update. Yes, it could well be.

 

I think looking at the version of the SnapCenter, you should be able to raise a ticket with NetApp. Have you already raised one regarding this issue ?  If not, I suggest please do so, chances are your issue will get resolved sooner.

 

Also, I come across this KB, talking about DNS issue. I guess you have acces to KBs. Please take a look.

SnapCenter Resource "Availability Group":
https://kb.netapp.com/app/answers/answer_view/a_id/1087384/loc/en_US

 

Thanks!

Re: SnapCenter on SQL cluster active-active

Yes, I have raised a ticket with NetApp.

 

Thanks for your help.

Re: SnapCenter on SQL cluster active-active

I added an sql server that is not clustered and the server registers correctly. The DNS resolution error only occurs with clustered computers.

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