Olav Aukan Getting information off the Internet is like taking a drink from a fire hydrant…

21Mar/11

How to backup SharePoint using PowerShell

Lately I've been reading up on - and experimenting with - PowerShell to automate alot of the tings I do in SharePoint. The original motivation was a deployment gone bad (ie. too many manual steps + too little time = too many errors) and it got me rethinking my whole approach to managing SharePoint.

My previous attempts at automating the build -> package -> deploy process with a .bat file calling MSBuild and STSADM commands had failed miserably about two years ago. It would not wait for the solution to finish retracting before trying to remove it, or it would try to activate a feature before the solution was finished deploying, etc. Also, since it was one giant monolithic script, any errors early on in the process would cause all sorts of problems.

There are ways to deal with this in .bat files, but they don't even come close to the cool stuff you can do with PowerShell! Therefore I'm planning on writing a couple of posts about using PowerShell to manage SharePoint based on the things I've been trying out so far. Keep in mind that I'm still learning and some of the stuff I write about might be stupid, inefficient or downright wrong. With that disclaimer out of the way I present my first PowerShell script: Performing a full farm backup.

# This function performs a complete backup of the local farm
function SP-Backup-Farm {

	param (
		[Parameter(Mandatory=$true, ValueFromPipeline=$true, Position=0)]
		[string]
		$BackupFolder
	)

	process {

		Write-Host "Attempting full backup of the farm."

		# Create the backup settings
		$Settings = [Microsoft.SharePoint.Administration.Backup.SPBackupRestoreSettings]::GetBackupSettings($BackupFolder, "Full");

		# Set optional operation parameters
		$Settings.IsVerbose = $true;
		$Settings.UpdateProgress = 10;
		$Settings.BackupThreads = 10;

		# File size details
		$BackupSize = New-Object UInt64
		$DiskSize = New-Object UInt64
		$DiskFreeSize = New-Object UInt64

		Write-Host "Backup Location:" $BackupFolder

		# Check that the target folder exists
		if (Test-Path $BackupFolder)
		{
			Write-Host "Backup Location Exists: True"
			Write-Host

			# Backup operation details
			$BackupID = [Microsoft.SharePoint.Administration.Backup.SPBackupRestoreConsole]::CreateBackupRestore($Settings);
			$BackupObjects = [Microsoft.SharePoint.Administration.Backup.SPBackupRestoreConsole]::FindItems($BackupID, "Farm");

			# Get file size info
			$BackupSize = [Microsoft.SharePoint.Administration.Backup.SPBackupRestoreConsole]::DiskSizeRequired($BackupID)
			[void][Microsoft.SharePoint.Administration.Backup.SPBackupRestoreConsole]::DiskSize($BackupFolder, [ref]$DiskFreeSize, [ref]$DiskSize)

			# Check if there is enough free disk space
			$HasEnoughSpace = $false
			if ($DiskFreeSize -gt $BackupSize)
			{
				$HasEnoughSpace = $true
			}

			$BackupSizeString = Util-Convert-FileSizeToString $BackupSize
			$DiskSizeString = Util-Convert-FileSizeToString $DiskSize
			$DiskFreeSizeString = Util-Convert-FileSizeToString $DiskFreeSize

			Write-Host "Total Disk Space:" $DiskSizeString
			Write-Host "Free Disk Space:" $DiskFreeSizeString
			Write-Host "Required Disk Space:" $BackupSizeString
			Write-Host

			if($HasEnoughSpace)
			{
				Write-Host "Sufficient Free Disk Space: True"

				# Set the backup as the active job and run it
				if ([Microsoft.SharePoint.Administration.Backup.SPBackupRestoreConsole]::SetActive($BackupID))
				{
					$BackupObjectCount = $BackupObjects.Count

					Write-Host "Successfully set backup job as the active job."
					Write-Host "Backup consists of $BackupObjectCount object(s)"
					Write-Host
					Write-Host "Backup Started"
					Write-Host

					foreach($BackupObject in $BackupObjects)
					{
						if (([Microsoft.SharePoint.Administration.Backup.SPBackupRestoreConsole]::Run($BackupID, $BackupObject)))
						{
							Write-Host "Backup Completed"
						}
						else
						{
							Write-host "An unexpected error occured!" -ForegroundColor Yellow
							Write-Host "Backup Failed" -ForegroundColor Yellow
						}
					}
				}
				else
				{
					Write-Host "Unable to set backup job as the active job." -ForegroundColor Yellow
					Write-Host "Backup Failed." -ForegroundColor Yellow
				}
			}
			else
			{
				Write-Host "Sufficient Free Disk Space: False" -ForegroundColor Yellow
				Write-Host "Backup Failed" -ForegroundColor Yellow
			}
		}
		else
		{
			Write-Host "Backup Location Exists: False" -ForegroundColor Yellow
			Write-Host "Backup folder doesn't exist or the service account does not have read/write access to it." -ForegroundColor Yellow
			Write-Host "Backup Failed." -ForegroundColor Yellow
		}

		Write-Host

		# Clean up the operation
		if (!$BackupID -eq $null)
		{
			[void][Microsoft.SharePoint.Administration.Backup.SPBackupRestoreConsole]::Remove($BackupID)
		}
	}
}

# This function returns a "user friendly" display value for a filesize in bytes
function Util-Convert-FileSizeToString {

    param (
		[Parameter(Mandatory=$true, ValueFromPipeline=$true, Position=0)]
		[int64]
		$sizeInBytes
	)

    switch ($sizeInBytes)
    {
        {$sizeInBytes -ge 1TB} {"{0:n$sigDigits}" -f ($sizeInBytes/1TB) + " TB" ; break}
        {$sizeInBytes -ge 1GB} {"{0:n$sigDigits}" -f ($sizeInBytes/1GB) + " GB" ; break}
        {$sizeInBytes -ge 1MB} {"{0:n$sigDigits}" -f ($sizeInBytes/1MB) + " MB" ; break}
        {$sizeInBytes -ge 1KB} {"{0:n$sigDigits}" -f ($sizeInBytes/1KB) + " KB" ; break}
        Default { "{0:n$sigDigits}" -f $sizeInBytes + " Bytes" }
    }
}

The convert bytes to string function was something I found on another blog and adapted to PowerShell, so I can't really take credit for that one. Also it took about 3 hours to do a full backup on my VMWare machine with about 50GB of content databases. Your milage may vary...

13Feb/10

Do you have a disaster recovery plan?

Do you have a disaster recovery plan?
There is a Creative Commons license attached to this image.

I did not...

A while back my Western Digital 500GB MyBook had a breakdown during the transfer of a batch of large files. This had happened to me a coupe of times before where Windows would display a Delay Write Failed error message, and some times it would have problems detecting the disk. Running scandisk and/or rebooting always seemed to fix the problem, so I didn't give it much attention, but this time it was different. The disk could no longer be detected by Windows, SpinRite or Western Digital's own maintenance tools. I tried the disk in several different computers with the same result.

When the system tried to boot the disk it would spin up and emit a series of rather loud clicking sounds before spinning down again. Many hours of googling led me to the conclusion that the disk had in fact suffered mechanical failure, and that I should have picked up the previous Delay Write Failed errors as a warning that the disk was about to fail. As it is now, the only option I have to recover the data is to have it sent to a data recovery specialist where they remove the data plates from the faulty drive housing and place them in a new one. This has to be done in a Class 100 Clean Room because even a microscopic spec of dust could lead to permanent loss of data when the disk is powered up again. Needless to say this service is not cheap.

This disk contained all my original RAW files from the last 2-3 years, and since I had never bothered to burn a backup DVD, these pictures are now most likely lost forever! The disk sits in my bookshelf as a grim reminder of my own stupidity awaiting the day I decide to fork out the big bucks and send it off for recovery. So the moral of the story is, always backup your files!