Can the Service Manager servers be put into Maintenance Mode or should they be excluded since they run the same back end as SCOM?
While System Center Service Manager uses the some of the same code as previous Operations Manager versions, the functionality they provide and how that code is used, has nothing to do with SCOM itself. Service Manager is mainly leveraging the workflow engine for processing data and communicating with the databases. As far as SCOM Maintenance Mode is concerned, these are just Managed Agents like any other server because Maintenance Mode is processed on the SCOM Management Servers.
For a bit of background:
There are two primary issues with a SCOM Management Server being in Maintenance Mode.
- Once a Management Server is in Maintenance Mode, it cannot take itself out of Maintenance Mode.
- A SCOM Management Server in Maintenance Mode will no longer process jobs/rules/sql stored procedures, or accept communications from agents, so all monitoring for every server it manages comes to a screeching halt. (In SCOM 2007, for the RMS, this meant the entire Management Group would be unmonitored, even if other Management Servers were still online.)
This was a major issue in SCOM 2007, however much of this has been resolved in 2012. Microsoft worked hard to make SCOM 2012 more scalable, and resilient. The achilles of SCOM 2007, was the Root Management Server. To get rid of that single point of failure in SCOM, Microsoft redesigned the Management Configuration Service, so that if a Management Server is unavailable its workflows will be moved to a different Management Server the Management Server Resource Pool.
That’s the catch… you have to be running more than one Management Server in the Management Server Resource Pool, or you will not see any benefit, because there is no place for the Management Configuration Service to move these functions too. In 2012, Management Servers can go in and out of Maintenance Mode, as long as there is always at least one Management Server in the All Management Servers Resource Pool to continue the work.
Maintenance Mode, is actually a SCOM Rule targeted at the Resource Pool. Because Service Manager Managment Servers, are not part of the Management Servers Resource Pool, (actually they’re not even part of the same Management Group), do not run SCOM Workflows, are not responsible for putting themselves in to or out of maintenance mode, and process no information from other agents, there is no issue using Maintenance Mode for these systems.