This is what I've to do.
The original idea was to install both Lync 2013 and SharePoint 2013 using Cluster availability.
But we discovered that Lync 2013 is no longer cluster aware.
Even like this, we want to install both product on same servers.
We came up with this idea which I would like to validate here:
1) Setup a 3 nodes SQL Server 2012 cluster for SharePoint instances with shared disks
2) On Server A (node 1 of the Cluster), install a standalone SQL Server 2012 with local disk acting as Principal server for the Lync 2013 mirror
3) On Server B (node 2 of the Cluster), install a standalone SQL Server 2012 with local disk acting as Mirror server for the Lync 2013 mirror
4) On Server C (node 3 of the Cluster), install a standalone SQL Server 2012 Express (or use existing clustered instance) with local disk acting as Witness server for the Lync 2013 mirror
Does it sound correct or did I miss something ?
I was tempted also to install Lync 2013 instances as Clustered instance on each Node (and not using Add node for node 2 and 3).
But I think the 1st option is better and simplier.