According to me, firsly I think you have to upgrade in order your epo server from EPO4.6.6 to EPO5.1. In this case, the 5 agent handlers will all time be connected to the new EPO 5.1
Concerning the upgrade, there are two options:
1- upgrade on the same physical computer
2- upgrade from the old physical server to a new physical server.
In which case are you?
We are using Windows Server 2008R2 (64bit).
The main problem/question is: Can I connect the OLD agent handlers 4.6.6 to the newly installed 5.1 ePO Server. And what is the best way to do it? They probably need to be updated first?
please read this:
Upgrade your remote Agent Handlers
When you upgrade your McAfee ePO server software, upgrade any remote Agent Handlers installed throughout your environment. Agent Handlers must be upgraded separately.
Remote Agent Handlers installed with previous versions of your software are not compatible with this new version, and are not upgraded automatically.
The upgrade process is a streamlined version of the procedure used for first-time installation of a remote Agent Handler, detailed in Install remote Agent Handlersunder Installing McAfee ePolicy Orchestrator software.
For more details see EPO 5.1 install guide at P47 https://kc.mcafee.com/resources/sites/MCAFEE/content/live/PRODUCT_DOCUMENTATION/ 24000/PD24807/en_US/epo_510_ig_0b00_en-us.pdf
I don't want to upgrade the old ePO 4.6.6 server, but my head systemadministrator wants me to start from scratch.
So first I need to install the new ePO 5.1 server. After that, upgrade the agent handlers. And let them connect to the new ePO server.
During Agent handler installation you type the machine name of the McAfee ePO server with which the Agent Handler must communicate.
So even if you upgrade the agent handlers, Would you modify the name of your existing epo 4.6 that is already on the agent handlers?
Do not forget that the agents do already search for the EPO Server 4.6 using IP/hostname etc
Communications are also protected with server keys.
I think, it will not be an easy job to do.
It will be better to perform an upgrade!
The name and ip for the new ePO server will be different. Can I stop the agent handler service and delete the old agent handler? After that is it possible to reinstall the new agent handler and connect to the new ePO server?
Use ePO 5.1 Agent Handler package and after installation copy db.properties files of new ePO server to agent handler. it will work.
Make sure all required ports are opened on firewall end and locally server outbound network connection.