I have seen a number of questions about different notifiation scenarios. I thought I could write down a comment to some of the most comment ones.

All alert for all machines within a group

In the “create new subscription wizard” unselect all groups and then select only the group including the current machines. Then select all classes and all alert criterias.

All alerts for a specified technology

In the “create new subscription wizard” unselect all classes and then select the current technology. For example if you want all alerts related to Active Directory, select all Active Directory classes.

All alerts for a specified technology on a specifyed machines

In the “create new subscription wizard” unselect all groups and then select only the group including the current machines. Then select all classes and all alert criterias. Unselect all classes and then select the current technology. For example if you want all alerts related to Exchange, select all Exchange classes.

All alerts an special alert

This in not as easy as in MOM 2005. But you can still solve it. Please take a look at this post and this post.

All alerts for all machines within a OU

Please take a look at this post.

All alerts for all machines within a AD Site

Start by create a new group within Ops Mgr. Configure dynamic members, select the Windows Computer class and choose Active Directory Site as property. The query formula should look something like this ( Object is Windows Computer AND ( Active Directory Site Equals Paris ) AND True ) . In this example the AD site is named Paris. In the “create new subscription wizard” unselect all groups and then select only the group including the current machines. Then select all classes and all alert criterias.

Pete and I wrote a guide about configure notification in Ops Mgr, you can read it here. If you need to configure notification on heartbeat failure, please take a look at this post. I have also written posts about alert aging and SMS notification.