How to disable backfilling?

[tornadocontrib]

Hello, my propose of running lighthouse lies on fetching tip blocks for EL and would like to know if it is possible to have pruning and disable backfilling to save disk space? Thanks.

[michaelsproul]

We don't support this usecase because it is detrimental to the health of the network. Ethereum relies on altruism of peers to a certain degree in order to keep blocks available and make it possible for other nodes to sync.

Lighthouse will only backfill 5mo of blocks by default. Once that's finished it won't backfill any more, however it also won't continually prune to a 5mo window. That feature isn't implemented yet:

• Prune historic blocks #3209