During the Medalla testnet I´ve been running a Lighthouse validator and beacon chain, but I´ve also had the prysm beacon chain running and synching in the backround. The thought is that I could switch over in case there´s a client bug in Lighthouse, without having to sync.
Is this a bad idea when mainnet launches? I´m not a developer so I´m not able to appraise the possible issues.
it is a good idea. there is even a dedicated validator client that attempts to automate the process of switching between different beacon chain nodes:
It is indeed a good idea. It might be overkill if you are not validating and just running a node (imagine running both Geth and OpenEthereum for Eth1), but if your machine can handle it, there should be no problem runing two beacon chains, and it’s a good precaution.