Getting a List of Stores in a PowerShell Script

In my last post, Getting a List of Storage Groups in a PowerShell Script, you saw how to use the information from the Get-StorageGroup cmdlet to discover the particular disk volumes used by a storage group and to build a list of the files that were used by the storage group.

Now, that list of files did not contain the databases contained within the storage group. Instead, it simply contained the system file (Exx.CHK) for each storage group and the log files (Exx*.LOG) for each storage group. This is because the Get-StorageGroup cmdlet does not return us that information. Instead, we use the Get-MailboxDatabase and Get-PublicFolderDatabase cmdlets to find out the name of our databases. It’s unfortunate, but there is not a single Get-ExchangeDatabase cmdlet that combines the functionality of both,

Note that in Exchange Server 2007, each database consists of a single file, with an extension of EDB. In Exchange Server 2003, there was also a second file per database called the streaming file with an extension of STM.

To remind you of the global variables being used:

• $computername is a string that contains the name of the computer on which the script is being executed.
• $volumes is a hash array that contains a list of all the disk volumes so far detected.
• $pathpattern is a hash array that contains a list of all the fully-qualified paths to all files so far discovered.

A store is always a simple filename. However, it’s important to remember that all of the file names that are used for naming stores and storage groups in Exchange Server may contain spaces and parentheses. That can lead to a requirement for special handling of file names.

When interrogating the list of stores on a particular server, any stores present in the Recovery Storage Group are also listed. These should be ignored.

Each cmdlet we use will return a collection. Get-MailboxDatabase will return a collection of all mailbox databases present on the given server. This collection could be empty even if storage groups are present. Get-PublicFolderDatabase will return a collection of all public folder databases present on the given server. This collection could also be empty (and, in fact, is more likely to be empty). The PowerShell code needs to be prepared to handle those eventualities.

In the PowerShell code below, the getStores function obtains all the stores on the server and adds the store filenames to the $pathpattern array and adds the disk volumes used by the stores to the $volumes array. Following getStores is the validateArrays function. If either the $volumes or the $pathpattern array is empty, it returns a value of 1 and displays a message on the PowerShell host. If both have contents, validateArrays returns a value of 0 and displays the contents of those arrays.

Without further ado:

function getStores
{
	## locate the databases, both mailbox and public folder

	$colMB = get-MailboxDatabase -server $computername
	$colPF = get-PublicFolderDatabase -server $computername

	## parse them for volumes too

	foreach ($mdb in $colMB)
	{
		if ($mdb.Recovery)
		{
			write-host ("Skipping RECOVERY MDB " + $mdb.Name)
			continue
		}
		write-host ($mdb.Name + "`t " + $mdb.Guid)
		write-host ("`t" + $mdb.EdbFilePath)
		write-host " "

		$pathPattern.($mdb.EdbFilePath) = 1

		$vol = $mdb.EdbFilePath.ToString().SubString(0, 1)
		$volumes.$vol += 1
	}

	foreach ($mdb in $colPF)
	{
		## a PF db can never be in a recovery storage group
		## which is why the Recovery check isn't done here

		write-host ($mdb.Name + "`t " + $mdb.Guid)
		write-host ("`t" + $mdb.EdbFilePath)
		write-host " "

		$pathPattern.($mdb.EdbFilePath) = 1

		$vol = $mdb.EdbFilePath.ToString().SubString(0, 1)
		$volumes.$vol += 1
	}

	return
}

function validateArrays
{
	$drives = $volumes.keys
	if ($drives.Count -lt 1)
	{
		write-host "No disk volumes were found. Aborting."
		return 1
	}

	write-host ("There were " + $drives.Count.ToString() + " disk volumes for Exchange server $computername. They are:")
	foreach ($drive in $drives)
	{
		write-host "`t$drive"
	}

	write-host " "

        $paths = $pathPattern.keys
        if ($paths.Count -lt 1)
        {
                write-host "No paths were found. Aborting."
                return 1
        }

	write-host ("There are " + $pathPattern.Count.ToString() + " directories to be backed up. They are:")
	foreach ($directory in $pathPattern.keys)
	{
		write-host "`t$directory"
	}
	write-host " "

	return 0
}

Until next time…

As always, if there are items you would like me to talk about, please drop me a line and let me know!

Follow me on twitter: @EssentialExch