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SQL 2012 - AlwaysOn FCI + AG

[ Edited ]

Hi,

Is the following setup supported / doable from a SQL 2012, SnapDrive & SMSQL perspective:

A local 2-node SQL 2012 AlwaysOn Failover Cluster Instance, stretched to a 3rd, remote node via AlwaysOn Availability Group?

Regards,
Radek

Re: SQL 2012 - AlwaysOn FCI + AG

While I have seen this run, it was set up via a workaround.  As stated below, it is not supported.

Re: SQL 2012 - AlwaysOn FCI + AG

Hi Justin,

Many thanks for your response.

In practical terms though - how do we provision LUNs with SnapDrive? AlwaysOn AG operates on top of a 3-node MS cluster, which includes 2 local & 1 remote node. SnapDrive plainly refuses to create a drive associated with local nodes only.

Thanks,
Radek

Re: SQL 2012 - AlwaysOn FCI + AG

In the meantime I figured out following workaround for creating LUNs:

  • MS cluster nodes at both sides need to have visibility of both local & remote filer and they need to establish iSCSI sessions with them
  • Create a LUN on a given node using SnapDrive – it has to be associated with all MS cluster nodes at this point
  • In MS Failover Cluster Manager, select storage object representing created LUN, open Properties, select Advanced Policies tab & limit Possible Owners to local nodes only
  • On the filer remove LUN mappings to remote nodes
  • Repeat for all required LUNs

Can anyone tell me if there is a less clunky method of achieving this?

Re: SQL 2012 - AlwaysOn FCI + AG

All,

     I don't want to create any confusion and I mean no disrespect, but the statement from "Welch" that this is a supported configuration is incorrect.  The IMT has no stated support for this configuration and I have run this post and question by 2 different Senior Support Engineers and this is their response:

"Combining a SQL FCI with an availability group is not supported in SnapDrive/SMSQL.  This is due to a limitation within SnapDrive that attempts to communicate with all nodes defined within the cluster object.

Typically, we would suggest that for these three nodes, each node have dedicated storage, rather than use a failover instance (with shared storage) in the primary location."

Re: SQL 2012 - AlwaysOn FCI + AG

Well, many thanks for your input - not the news I was hoping for, but at least we have some movement in this thread!

Re: SQL 2012 - AlwaysOn FCI + AG

Has this situation changed? Has been that Snapshot Limitation been corrected? FCI provides some benefits different to the AlwaysOn. How can we raise the important of this support?

Re: SQL 2012 - AlwaysOn FCI + AG

We are looking at aquiring NetApp as our SAN solution and our planned configuration for the SQL\cluster architecture was the same\similar as described here.  Of course the sales people said it i was no issue.  It sounds like it actually is.    I am interested in more information on what you did as a solution, or was it just a work around?  Since I am in the beginning stages I want to make sure I set this up right the first time.