Buried in the massive amount of new features introduced with vSphere 5 there are several new API methods on the HostStorageSystem managed object.
Two of these API methods will allow you to automate the new Attach/Detach LUN feature from the vSphere Client. It concerns the AttachScsiLun and DetachScsiLun methods. Until this new feature is available natively in PowerCLI, you can use the following functions.
An interesting question arrived in my mailbox this morning. Robert wanted to know what was the most efficient way to create a new property, called lunID, for the objects returned by the Get-ScsiLun cmdlet.
The new property had to show the lunID, as it is returned in the LUN column in the vSphere client.
A quick post that is triggered by a tweet from @GernotNusshall I saw passing today. He wanted to know how to find the maximum IOPS values over the last 5 minutes for a number of VMs. The IOPS values are readily available from the vSphere statistics but the problem is that the values are returned as summation values over the measuring interval and that you have a read and a write value.
An ideal job for PowerShell to get the values Gernot was after.
When you are running multi-node vSphere clusters, you probably already had the experience that one or more of your LUNs were not visible on all nodes. Now you can try to find out which LUN is missing on which node the hard way through the vSphere client. Or you can use the force of PowerCLI and run a script that will report all this in a handy spreadsheet.
To make the script as flexible as possible it should be able to handle any n-node cluster. And as you some of you might know, the Export-CSV cmdlet has some problems with variable length rows. Luckily there is a handy solution I already used in my yadr – A vDisk reporter post.
