As is the case in Operations Manager, all customizations for notification templates, groups, list items, workflows etc. in Service Manager are stored in Management Packs. A management pack can consist of two types;
Sealed and Unsealed.
A sealed management pack has a .mp extension and can not be modified directly. So Microsoft, other vendors or you can prevent modifications on Management Pack itself.
Unsealed management packs have a .xml file extension and con be modified with SM console, authoring tool or directly within XML file.
For example, if you want to add list items to a list that is defined in a sealed management pack, you have to store this modifications in a unsealed management pack. Or if you want to add some fields to a form that is defined in a sealed management pack, again you have to store modifications in an unsealed MP.
Just because of this certain rule,
A MP (sealed or unsealed) can depend on a sealed MP.
A MP (sealed or unsealed) can depend on an unsealed MP.
Lets think about following scenario;
You create a new Management Pack in Service Manager 2012 which includes custom forms, notification templates and item lists. After a couple of months, other SM administrator created another Management Pack for a custom need and that MP references for list items and other objects to your firstly created MP. In case of such a scenario your first MP must be sealed to have base definitions for other MP’s in your organization.
Sealing a management pack is easy and clear process. First requirement to seal an MP is signing the file to ensure that file is not modified when you transfer it between locations. So before sealing a MP you must create a key pair with Strong Name Tool (sn.exe). Key pair will have an .snk extension.
Strong name tool is automatically installed with Visual Studio. Also if you installed Microsoft .NET Framework 4.0 on your machine sn.exe is available in the following location;
%ProgramFiles%Microsoft SDKsWindowsv7.0AbinNETFX 4.0 Tools
To create key pair, at the command prompt run the following command;
After you created snk key pair, in the Auhtoring Tool, in the management pack explorer right click an unsealed MP and choose "Seal Management Pack”.
Then choose your key pair and fill out company field.
Now you can easily import your sealed management pack through Service Manager Console.