In this article, we are going to see how to add a new disk to an existing SQL Server failover clustered instance (which I will be referring as FCI from now on). Let’s assume a scenario where you have an existing FCI with dedicated data and log drives and you want to add a new disk (Let’s say you have a new requirement to store your backups locally).
I will be demonstrating this in my lab setup where I have a two node failover clustered SQL Server 2017 Instance, running on Windows Server 2012 R2. Below is the current state of my FCI from failover cluster manager.
As you can see I have two disk drives (E$-SQLData and F$-SQLLogs) dedicated to my SQL Server Instance. Now I would like to add a new disk with volume label SQLBacks. First thing first, we need to carve a new disk from SAN and present it to windows (This part will be typically done by Storage admins and or Windows admins depending on your organization). FYI, in my lab environment for the demo purposes, I am leveraging windows server iSCSI for building my SAN infrastructure. In order to create a new disk drive and present to both the nodes of my failover cluster, I am going to create a new iSCSI virtual disk from my SANDC machine. This is the server which acts as Domain Controller and SAN (File and Storage Services role has already been installed and configured) in my lab environment.