add logging about relay status

[newearthmartin]

Currently logs only consist of status of messages, like this:

... msg="http: POST /eth/v1/builder/validators 200" duration=1.155462 method=POST path=/eth/v1/builder/validators status=200 version=v1.6

And eventually there are some logs about errors:

... msg="error calling registerValidator on relay" error="Post \"https://bloxroute.max-profit.blxrbdn.com/eth/v1/builder/validators\": context deadline exceeded (Client.Timeout exceeded while awaiting headers)" method=registerValidator numRegistrations=2 ...

What does that mean? is it a temporary error? should I be concerned?

So, it would be great to have logs about the actual status of relays. For example lighthouse consensus client says this:
Connected to beacon node(s) synced: 1, available: 1, total: 1, service: notifier

Would it be possible to add a line every now and then that says the total number of relays, how many are connected, how many have problems, etc? It is important to give users a reassurance that everything is working ok.

[metachris]

mev-boost only contacts the relays when the CL client tells it to. And only at that point does it seem relevant which relays are able to respond just then with a bid.

You can run mev-boost with -relay-check and it will check and print the status of all relays on startup!