Lnd: I tried to restore wallet from seed but channels were not restored. Is it ok?

[Perlover]

Background

I tried (in testnet) to use restore wallet from seed but channels were not restored. Is it ok? I don't see any documentation about backups & restoring but i had read issue closed tickets and i think it should work from seed because keys of channels are deterministic from seed. And data loss feature is there already (without anouncing to nodes)

Your environment

• version of lnd 0.4.2-beta commit=7cf5ebe2650b67...1f1d6e19
• which operating system (uname -a on *Nix) CentOS 6.*
• version of bitcoind - 0.16.0
• any other relevant environment details

Steps to reproduce

1. I have node_1 at IP_1 with opened channels
2. Shutdown node_1
3. We should have node_2 with same version of lnd, not to be run and IP_2 (different IP)
4. To run bitcoind @ node_2 and wait of syncing with blockchain
5. To run first time the lnd. I do lncli create. It was asked: i have seed or nor. I enter seed of node_1 and password of seed

6. After i see in logs:

   Wallet recovery mode enabled with address lookahead of 250 addresses
   ...
   RECOVERY MODE ENABLED -- rescanning for used addresses with recovery_window=250
   

Expected behaviour

I wanted to see opened all channels.

I think that this is a working situation, when node changes IP and/or port. The main ID of node is public key. When i shut down node_1 and ran node_2 other nodes in the lightning network should anounce new IP (and may be port) and third party nodes with opened channels should reconnect after this.

Actual behaviour

I saw that public key of node is same. walletbalance has non-zero value. But after lnd running 24 hours already i didn't see any old opened channels. The channelbalance was zero too.

After i shut down node_2 and ran node_1 again. Now the node_1 has same opened channels which had before shutting down.

I didn't do it with same IP because i didn't want to make and restore binnary files. I think that this is a working situation, when node changes IP and/or port. The main ID of node is public key. When i shut down node_1 and ran node_2 other nodes in the lightning network should anounce new IP (and may be port) and third party nodes with opened channels should reconnect after this. But it doesn't happen.

[halseth]

Channels not possible to recover from just the seed at this point.

[Perlover]

Only binary (wallet.db & channel.db files?) method?

[halseth]

Only binary (wallet.db & channel.db files?) method?

?

[Perlover]

My question was: if now the seed restore for channel not realised - have i only way to backup binary files?

$datadir/chain/bitcoin/mainnet/wallet.db
$datadir/graph/mainnet/channel.db

Right? Or it will not help to restore LN node?

[halseth]

Yeah, but if the binary files is not the latest state, you risk that using them might be considered a channel breach.

[Perlover]

you risk that using them might be considered a channel breach.

Yes, i know it (_Breach Remedy_ transaction from other side of channel).
I hope that the seed restoring for channel will be realized soon.

[Roasbeef]

You must understand that channels are stateful. You need the seed _plus_ the state.

[brandoncurtis]

@Roasbeef if wallet.db and channel.db are _continuously_ backed up, should that be sufficient to restore channel balances in the event of a failure? Would backing these up properly require stopping lnd?

[vindard]

@brandoncurtis my understanding is that it isn't since there could be data that's stored in memory and not written to those db files immediately once lnd is running.

By stopping lnd you ensure that everything in-memory gets written to the files, but this isn't a good solution since that means your node would be spotty for connectivity/routing