I am not sure if I understood how to set up the Distributed Management Console correctly.
So I have two independent indexers, two search heads, and a bunch of heavy forwarders - I'd like to monitor them all with the DMC.
The setup manual states that I have to configure each instance that I want to monitor as a search peer for the DMC. In another part of the manual (prerequisites), it is written that I have to forward the _internal logs of all other systems to the indexers (I do this for all systems already).
So should I deactivate the _internal forwarding for all the systems I want to monitor with the DMC, or is it sufficient to point the DMC to the indexers (all _internal logs are there)?
If I were you I would keep forwarding all of your internals to the indexers and add all of the systems (SHs, Is & HFs) to the DMC as search peers.
One reason you want to add all of them as search peers even though you have forwarded all of the internals is because a number of the searches and precanned alerts from the DMC make use of REST calls as well as looking at the internal indexed data.
The reasons to forward the internals to the indexers doesn't change with the DMC so keep doing that.