yes i believe it is called out in the documentation that the SEPM server needs a static ip addres.

It does require static IP since the clients need to know which computer to look at for def. updates, that's if the clients are managed by the console.

Actually SEPM does not require a static IP although it is recommended.  The clients find the SEPM through a Management server list for the site.  When you install/create the SEPM manager/site a default server list is created.  It includes the current IP address and the host name for SEPM.  If you install SEPM on a machine without a static the clients will need to use only the name of SEPM and it must be resolved by the client to the SEPM manager. You will need to create you own Management Server list (you can’t edit the default list) with the host name(s) of SEPM and the clients will resolve the name using DNS, WINs, or NetBIOS Broadcast depending on your network config. 

how about clients? I believe clients wouldnt need static IP as well? Can it affect the SEPM from tracking the clients?

- How does SEPM track clients? by MAC address AND by computer name? or..it's either one?

When the clients connects to the SEPM manager it registers itself and gets an agent Id.  This is how it is tracked.  The SEPM manager never contacts the client.  The client always initates the communication to SEPM.  You can configure the communication in Push or Pull mode.  With PUSH mode the clients conects to the SEPM and maintains a connection.  With PULL mode the clients connect to SEPM at a hartbeat intervial checks for updates and disconnects.   

 

Agent registration is triggered by theses specific events

• The first time the agent contacts the Policy manager after installation
• The Agent ID or Host ID in the local registry is remover and the Agent is Restarted and contacts the Policy Manager for a new ID
• Agent receives a 412 status code from the Policy Manager. Usually this happens when the Agent is deleted from the Policy Manager
• When the Agent is in user-based mode and a new user log onto the PC.