What are best practices for checkpointing/saving EOSIO chain data in a way that can be restored relatively quickly into the nodes, in case of some corruption in the live chain?
I think you could copy out the data in ~/.local/share/eosio/nodeos/data/ which are two directories blocks and state. Restoring these two directories to a previous state should make it work again. Be sure to have stopped nodeos before copying the stuff out. If you stop nodeos like normal I don't see why it wouldn't restart like normal if you restore these files to their previous state.