If you’re like me you don’t allocate all disks to a SAN out of the gate.  I like to keep a little in reserve so I can add capacity when needed.  Then, once all the disks are added I’ll usually pickup a couple more disks and keep those in reserve.  In either case once it comes time to add capacity to a virtual disk on a Dell MD 3000i SAN it can be a little tricky.

This will be accomplished in two steps.  First add the capacity of one or more physical disks to a disk group.  Next expand the virtual disk.  The first step is rather easy and done through the Modular Disk Storage Manager utility.  Step two is a little tricky as it uses the Dell smcli command line utility.

Step 1 – add one or more drives to a Disk Group

• Open the Dell Modular Disk Storage Manager utility
• Click the Modify tab
• Under the Storage subsection click Add Free Capacity (Physical Disks)
• Select your disk group, click next
• Select the capacity/number of disks, click finish

NOTE: This step can take some time to complete. Depending on the size and type of RAID you are running, it may take several hours or more (even days!) to complete. It will not take the disk group down, but may slow things a bit.  Also, this MUST complete before you can perform the next step!  If you jump the gun and run step two prematurely you’ll receive the message, “Error 11 – The operation cannot complete because a virtual disk is performing a modification operation…”

Step 2- Expanding a Virtual Disk

• Decide how much space to add in Bytes.  You could use a calculator such as this or this bit calculator.
• On the computer running Dell Modular Disk Storage Manger, open a command prompt.
• Navigate to Program FilesDellMD Storage Managerclient OR Program Files (x86)DellMD Storage Managerclient if you are on a 64 bit machine.
• Use the smcli command to expand the disk. Examples below.

smcli Syntax: smcli ArrayName -c "set virtualDisk ["virtualdiskname"] addCapacity=virtualdiskcapacityinbytes;"

Example smcli command – assumes the following:

• MD3000i named SAN1
• Virtual Disk named Disk1
• Want to add 500GB to virtual disk

smcli -n SAN1 -c "set virtualdisk ["Data1"] addCapacity=536870912000;"

While this expands the capacity of the SAN virtual disk the operating system may not automatically recognize it.  On Windows 2008 server perform the following:

• Open Server Manager 
• Go to Storage, Disk Management
• Right-click the desired Windows volume and select Expand Volume
• Follow the prompts in the Extend Volume Wizard