Here’s a quick one – you want to update the failover management servers on your agents en-mass, and don’t want to wait 12 years for it to complete. Why do you want to set it? Maybe you only want certain agents talking to certain data-centers, or specific management servers have very limited resources. Regardless of the reasons, if you do need to update the agent config, it can be a bit slow. Here is a quick little script that can make those update a LOT quicker.
First thing first – download PoshRSJob from Boe Prox. It’s about the best thing since sliced bread, and I use it constantly. Download the module and place it in one of your module directories (C:\Windows\System32\WindowsPowerShell\v1.0\Modules, for example). Next, create a CSV called FailOverPairs.csv. This should have 2 columns – Primary and Failover. For example:
Primary,Failover
MS01,MS02
MS03,MS04
MS05,MS06
You will want that header line – mainly because it saves us a couple of lines of code in PowerShell. Next, save that CSV in the same directory as the script below. This CSV will be used to set the appropriate failover partner. Save the script below in the same directory as the csv, and you are good to go! Here is the script:
Import-Module PoshRSJob -Force
Import-Module OperationsManager -Force
$modules = (Get-Module | Where-Object{ $_.Name -notlike 'Microsoft.*' -and $_.Name -ne 'PoshRSJob' -and $_.Name -ne 'ISE' }).path
try
{
$agents = Get-SCOMAgent
}
catch
{
write-verbose "Cannot load agent list"
}
$Pairs = Import-Csv -Path $PSScriptRoot + '\FailoverPairs.csv' -Header Primary,Failover
$agents|Start-RSJob -Name { $_.DisplayName } -Throttle 20 -ModulesToImport $modules -ScriptBlock {
param($agent)
$Pairs = $using:Pairs
$primary = $agent.PrimaryManagementServerName
$CurrentFailover = ($agent.GetFailoverManagementServers().DisplayName)
foreach ($Pair in $Pairs)
{
if ($Pair.Primary -eq $primary){$secondary = $Pair.Failover}
if ($Pair.Failover -eq $primary){$secondary = $Pair.primary}
}
if ($secondary -ne $CurrentFailover)
{
$AgentName = $agent.DisplayName
write-verbose "$AgentName Secondary wrong. Primary $Primary, Current Secondary $CurrentFailover, Discovered Secondary $secondary"
try
{
$Failover = Get-SCOMManagementServer | Where-Object {$_.Name -eq $secondary}
if ($Failover.IsGateway -eq $true)
{
$FailOverServerObject = Get-SCOMGatewayManagementServer | Where-Object {$_.Name -eq $secondary}
}
else
{
$FailOverServerObject = $Failover
}
Set-SCOMParentManagementServer -Agent $agent -FailoverServer $FailOverServerObject
write-verbose "$AgentName $secondary set."
}
catch
{
$ErrorText = $error[0]
write-verbose "$AgentName Failed to set failover. Current Failover $CurrentFailover, Discovered Failover $secondary.$ErrorText"
}
}
}|Out-Null
get-rsjob|Wait-RSJob|Remove-RSJob -force|Out-Null
Let’s examine some of this – the imports are obvious. If you have any issue with unblocking files or execution policy, leave a comment and I will help you through the import. The next line is different:
$modules = (Get-Module | Where-Object{ $_.Name -notlike 'Microsoft.*' -and $_.Name -ne 'PoshRSJob' -and $_.Name -ne 'ISE' }).path
What we are doing here is to get a list of the loaded modules, then exclude some of them. We are doing this because when we run this script, we are creating a ton of Runspaces. By default, these runspaces will need to know which modules to load. We don’t need them to load PoshRSJob, and we don’t need them to load things like the ISE because they are ephemeral – they will go away after they have completed their processing. This line can be modified if you don’t need to load other modules. It will load the OperationsManager module, which is the heavy lifter of this script.
Next, we get all of the agents from the management group. This script needs to be run from a SCOM server, but you could easily modify this script to run from a non-SCOM system by adding the “-computername” switch to the get-scomagent command. Then we import the CSV that contains our failover pairs.
Now the fun starts – this line starts the magic:
$agents|Start-RSJob -Name { $_.DisplayName } -Throttle 20 -ModulesToImport $modules -ScriptBlock {
This is the magic. We are feeding the list of SCOM agents (via the pipeline) to the start-rsjob cmdlet. The “-name” parameter tells the runspaces to use the Agent name as the job name, and the “-Throttle” parameter is set to control the number of runspaces we want running at once. I typically find that there isn’t a lot of benefit to going much over 2 or 3 times the number of logical cores. Maybe if you have remote processes that were very long running it might be beneficial to go up to 5-10 times the number of processors, but for this I found 2-3 to be the sweet spot. You will also see that we are telling start-rsjob what modules to import (see above).
The rest of the script is the scriptblock we want PoshRSJob to run. This is actually pretty straight forward – we set some variables (some of the we have to get with “$using:“). Then we find the current primary and failover, see if they match our pairs, and if they don’t we correct them. This isn’t a fast process, but if you are doing 20 of them at a time, it goes by a lot faster!
At the end of the script, we are simply waiting for the jobs to finish. In fact, if you want to track the progress, comment out this line:
get-rsjob|Wait-RSJob|Remove-RSJob -force|Out-Null
If you comment that line out, you can track how fast your jobs are completing by using this:
get-rsjob|group -property state
We’ve been able to check several thousand systems daily in very little time to make sure our primary and failover pairs are set correctly. I hope you guys get some use from this, and go give Boe some love for his awesome module! Leave a comment if you have any questions, or hit me up on Twitter.
