Keys
Your Lightning node or wallet will have keys. Look at Backup for instructions.
Bitcoin key (on-chain)
A wallet and lightning node usually hold bitcoins to open channels. If you backup this key you can get your on-chain balance back.
Making backups is not easy. Probably just take your wallet-file... See github for more info.
If you’re putting a lot of money on your Lightning routing node, please use a reliable hard drives (with mirroring).
The mnemonic seed is NOT enough to recover funds from channels if something goes horribly wrong, you’ll need the latest chan state.
Data Loss Protection
Channel information
LND
Tip for now, just backup the whole ~/.lnd directory. Template:TODO
There is work underway to make backup better in 6.0: https://github.com/lightningnetwork/lnd/pull/1364
Commitment revocation private key
Every commitment transaction has a unique commitment revocation private-key value that allows the other peer to spend all outputs immediately: revealing this key is how old commitment transactions are revoked. To support revocation, each output of the commitment transaction refers to the commitment revocation public key.