Suggested ways to make sure watchtower is keeping up

[Jontified]

We would love to be able to track if our watchtower is keeping up with the channels it is watching over. We were wondering what you suggest as the best way to track this. Currently we're thinking that the num_backups field of the wtclient seems like a plausible candidate. Ideally we'd have a metric that tracked this on the watchtower side but as far as we can tell lnd does not make this available.

So we figured we'd ask you:

1. What do you think are the best ways to track that the watchtower has backed up the latest channel state
2. What do you think about adding the wtclient stats metric to lndmon?

[bitromortac]

I think using num_backups is currently the best way to track it client-side using the RPC. Right, I don't think you can query internal state of the watchtower itself.

What do you think are the best ways to track that the watchtower has backed up the latest channel state

You could check logs to see if backups arrive. Use lncli debuglevel WTWR=debug on the watchtower side and lncli debuglevel WTCL=debug on the client side to enable more detailed logs.

What do you think about adding the wtclient stats metric to lndmon?

This is a great suggestion and should be straightforward to add.

[Jontified]

I think using num_backups is currently the best way to track it client-side using the RPC. Right, I don't think you can query internal state of the watchtower itself.

What do you think are the best ways to track that the watchtower has backed up the latest channel state

You could check logs to see if backups arrive. Use lncli debuglevel WTWR=debug on the watchtower side and lncli debuglevel WTCL=debug on the client side to enable more detailed logs.

What do you think about adding the wtclient stats metric to lndmon?

This is a great suggestion and should be straightforward to add.

Seems reasonable! I am realizing that lncli wtclient stats only gives you stats since the latest restart. I am thinking that the more interesting metric to track would be the absolute amount of backups given by lncli wtclient tower <pubkey> --include_sessions. What do you think about adding that metric instead? Or potentially both?

[Jontified]

Hi! I've looked a bit at doing this and it seems like we would need to add the watchtower interface to https://github.com/lightninglabs/lndclient because as far as I can see that isn't there yet.

I was thinking I'd implement a watchtower collector with the focus on num_backups. Before that I suppose I'll have to try to implement the gRPC interface for watchtowers in lndclient.

Does this seem like a reasonable plan from your pov?