In SCCM, there is a handy field that allows you to quickly see if clients are online. This is the Device Online Status field. However, it can happen that all or almost all of your customers are displayed offline. It is of course unlikely that no users are working, even if it is a public holiday.
You will probably have the reflex to look at the status of your client on your own machine. Everything is fine on your end, your client is communicating well with your primary server. On this same server, you try to communicate with your computer. By doing a remote control, you notice that the server is also communicating with your computer.
Since the problem is general, it could be either a network flow that has been cut or a server that has fallen. Let’s look at the latter possibility.
Checking the management point
In Monitoring, go to System Status, then Component Status. There, you may notice that the SMS_MP_CONTROL_MANAGER component is in critical status. If this is the case, right click on it and select View Messages, then Error.
A new window appears, choose a week. You will then see the error history for 1 week. The one we are most interested in is the one with the message ID 5436. The description is explicit, the management point does not respond to http requests.
When you look at your infra, you will surely see that the server used as a management point is KO’d, or that the communication is broken. For my part, the system partition was saturated with IIS logs in the inetpub folder. No more disk space and the server crashed.
If you are also experiencing problems with log files, you might be interested in this article: How to purge IIS logs with 4 methods
Offline clients: conclusion
In conclusion, if you see all your clients offline, consider checking the status of your management point and whether it is communicating with the clients and the primary server.