How to safely run more than one Tor relay
You can run more than one Tor relay to contribute additional bandwidth to the network, but you must configure them properly to maintain user anonymity and network diversity.
If you want to run several relays to donate more to the network, we're happy with that. But please don't run more than a few dozen on the same network, since part of the goal of the Tor network is dispersal and diversity.
If you do decide to run more than one relay, please set the "MyFamily" config option in the torrc of each relay, listing all the relays (comma-separated) that are under your control:
MyFamily $fingerprint1,$fingerprint2,$fingerprint3
where each fingerprint is the 40 character identity fingerprint (without spaces).
That way, Tor clients will know to avoid using more than one of your relays in a single circuit. You should set MyFamily if you have administrative control of the computers or of their network, even if they're not all in the same geographic location.