Understanding client health  :

http://blogs.technet.com/b/configmgrteam/archive/2011/05/03/client-health-in-configuration-manager-2012-beta-2.aspx

Dear Experts,

We are implementing System Center Configuration Manager 2012 R2 Agent on all Client Machines. After Completing the installation, Few Machines are showing the state as Inactive.

We have tried to Re-install the agent on those Machines manually, and it is getting reported as Active.

We would like to know, what could be the possible cause for this issue? We do not have Client Push Installation on our Environment. 

Your advises pls.

Regards,

Hi Veera,

Client status as inactive can have many reasons.

1. Machine offline and not to network for long.

2. SCCM client getting corrupt.

3. Machine no able to find MP.

4. DNS/Admin$ access issue on the client machine.

You have to examine client side logs (before reinstalling it) in order to get an idea why communication is no longer happening.