Passing active powershell Session to background jobs - powershell

Question

I am writing a powershell script to manipulate Exchange Online mailboxes.
I want this script to run with background jobs in parallel, so I'm trying to use PoshRSJobs (https://github.com/proxb/PoshRSJob) to create the jobs.
My code is:
Connect-ExchangeOnline -Credentials ...
Start-RSJob -ModulesToImport ExchangeOnlineManagement -Throttle $ProcesosConcurrentes -InputObject $jobs -ScriptBlock {
./migra_buzon.ps1 ...
}
Where:
$jobs is an arraylist where I have the parameter of the mailboxes I want to operate with
migra_buzon.ps1 is another powershell scripts that operates over one specified mailbox
The problem I have when I run this way is that in the jobs I have the error:
The term 'Add-MailboxPermission' is not recognized as a name of a cmdlet, function, script file, or executable program.
Check the spelling of the name, or if a path was included, verify that the path is correct and try again.
Although other commands like Get-EXOMailbox are working correctly.
Looking for help I found that the problem can be related with the session, so I changed my code to:
Connect-ExchangeOnline -Credentials ...
Start-RSJob -ModulesToImport ExchangeOnlineManagement -Throttle $ProcesosConcurrentes -InputObject $jobs -ScriptBlock {
$o365session = New-PSSession -ConfigurationName Microsoft.Exchange -ConnectionUri "https://outlook.office365.com/powershell-liveid" -Credential $(Import-Clixml $Using:ExchangeCredentials) -Authentication "Basic" -AllowRedirection
Import-PSSession $o365Session -CommandName #('Add-MailboxPermission', 'Get-MailboxPermission')
./migra_buzon.ps1 ...
}
In this case, the problem I have is with the Exchange connection. After running a few jobs I'm getting the error:
[outlook.office365.com] Processing data from remote server outlook.office365.com failed with the following error message: Client did not get proper response from server. For more information, see the about_Remote_Troubleshooting Help topic.
Cannot validate argument on parameter 'Session'. The argument is null. Provide a valid value for the argument, and then try running the command again.
So my question is, what is the right way to run background jobs sharing the connection got in the main process?
Thanks
PS: I first tried to run jobs with Start-Job, but with this the problem is that each background job needs its own connection, so I got and maximum number of connections exceeded. And this is the reason I changed my code to Start-RSJob

Answer 1

It appears that you are hitting Exchange Online throttling limits.
If that indeed the case, you can try the following method.
How to relax PowerShell throttling
There is a relatively new customer facing way to increase or update PowerShell Throttling Policies.
Go to Microsoft 365 admin center.
Validate that you are logged in with the user that has the correct role assignment.
Click on the Need Help? Widget in the bottom right corner
Graphical user interface
Type Exchange PowerShell throttling in the search box and select “Temporarily update throttling policies for a migration”. Keep in mind that this is only applicable for 90 days. After 90 days, the throttles will return to back to the default values for that tenant.

Answer 2

MachSol offers Tenant management using a job engine, that allows you to do multiple operations using front-end and let the jobs handler take care of processing in background. You can give it a try:
https://www.machsol.com/machpanel-automation-for-microsoft-CSP-partners/