Veeam and PowerShell: A perfect match!

I read a really good and useful blog post a while ago from Preben Berg from Veeam describing how to use PowerShell to restore a database from backup to a dev environment. This made me think on another scenario that would be fun to script that might come in handy someday.

What if you have a SAN that you would want do snapshots on once an hour and save some of those historical snapshots rotating the oldest one.

Now for the disclaimer part, this is merely meant to showcase how you might accomplish this. There are no safety features built in. Do not use it in production and use it at your own risk. However if you’d like to do some further testing of your own, you can download a virtual SAN from HP – free of charge up to 1 TB. Nice!

First things first. We need to create a PowerShell script.

Let’s define which volume to use:
$source_vol_name = "datastore1"

Then we add a naming convention to use for the snapshots with a timestamp at the end:
$snapshot_name = "Oh_snap_"+(Get-Date -Format MMddhhmm)

Let’s count how many snapshots exist on the volume:
$snapshot_count = @(Get-HP4Volume -name $source_vol_name | Get-HP4Snapshot).Count

Now let’s create a snapshot:
$snapshot_create_session = Get-HP4Volume -name $source_vol_name | Add-HP4Snapshot -name $snapshot_name -description "Automated snapshot"

I would like to save the 4 latest snapshots on the volume and delete the oldest:
if ($snapshot_count -ge 4 {
$snapshot_remove_session = Get-HP4Volume -name $source_vol_name | Get-HP4Snapshot | Sort-Object creationtimeutc | Select-Object -First 1 | Remove-HP4Snapshot
}

If I would leave out ”Get-HP4Volume -name $source_vol_name”  in the above statement then I would delete to oldest snapshot available on any of the volumes (not just datastore1) which is not our intent.

Let’s put it all together:

Add-PSSnapin VeeamPSSnapIn -ErrorAction SilentlyContinue

$source_vol_name = ”datastore1”
$snapshot_name = ”Oh_snap_”+(Get-Date -Format MMddhhmm)
$snapshot_count = @(Get-HP4Volume -name $source_vol_name | Get-HP4Snapshot).Count

$snapshot_create_session = Get-HP4Volume -name $source_vol_name | Add-HP4Snapshot -name $snapshot_name -description ”Automated snapshot”

if ($snapshot_count -ge 4 {
$snapshot_remove_session = Get-HP4Volume -name $source_vol_name | Get-HP4Snapshot | Sort-Object creationtimeutc | Select-Object -First 1 | Remove-HP4Snapshot
}

That’s all, just a few lines of code and we can accomplish cool things.

Then all we have to do is add the script as a scheduled task on the VBR server and run it once an hour or what ever intervall we’d like.

But let’s see how the infrastructure looks prior to running the script:

1. SAN datastores

 

Open Task Scheduler and create a new task:

2. Create scheduled task

 

Let’s configure it to run once an hour starting at 10 PM:

3. Run at 1 hour intervall

 

We add and action, starting the PowerShell script:

4. Add PowerShell script to run

 

Looks ok once it’s added:

5. Scheduled task has been added

 

First time the script ran a snapshot was created as expected:

6. First run of the script

 

(I changed the script to run every 5 minutes to speed up the process), now we have 4 snapshots:

7. 4 initial snaps

 

When the fifth snapshot has been taken the oldest snapshot is deleted (the snapshot created at 10:07 PM in the previous picture):

8. 4 snaps rolling