The Management Packs of System Center Operation Manager (SCOM) are the components that tell SCOM what to monitor and when to generate alerts.
So, to allow SCOM to monitor Exchange Server, you’ll need to import the Exchange server MP, and so on.
Microsoft offers MPs that allow SCOM to monitor Microsoft Products, a list of Microsoft MPs can be found at: http://social.technet.microsoft.com/wiki/contents/articles/16174.microsoft-management-packs.aspx
Also, 3rd party vendors offer different MPs for SCOM. For example, Veeam offers a MP that allows SCOM to monitor ESXi servers. a list of MPs from 3rd part vendors can be found at: http://www.concurrency.com/blog/comprehensive-list-of-scom-2012-sp1-management-packs-almost/
In addition, Community offers some MPs for SCOM, you can find them at:
You can Import SCOM MPs either directly from the Catalog (only for Microsoft MPs), or by pre-downloading them then import them from the disk.
Stanislav Zhelyazkov have create a powershell script that allows you to download all Microsoft Management Packs for SCOM 2007, R2 and 2012. The Script can be found at: https://gallery.technet.microsoft.com/scriptcenter/All-Management-Packs-for-37d37902
As we go with SCOM, we would have many customized MPs that we’ll need to backup, for this you can use the following commands:
OpsMgr 2007 R2
get-managementpack | export-managementpack -path D:\mgmt\MPBackups
Get-SCManagementPack | Export-SCManagementPack -path D:\mgmt\MPBackups