Add hints to port conflict and lock file panics

[oxarbitrage]

Motivation

The port conflict and the lock file messages are hard to understand. We want to add a hint so the user can rerun with a fixed configuration.

Solution

We add 2 panics in this PR with custom messages. We filter the issue url as we don't want users to report this as it is expected to happen if they have another instance of zebrad running in the same machine.

There are 3 different ports that can conflict, and the lock file can conflict:

• metrics listener (Add a hint to the port conflict panic #1484)
• tracing listener (Add a hint to the port conflict panic #1484)
• Zcash network protocol listener (Add a hint to the "Address already in use" error #1509)
• RocksDB LOCK file (Improve log message for RocksDB LOCK file panic #1508)

We need to cover all 4 cases in this PR.

The code in this pull request has:

• Documentation Comments
• Unit Tests and Property Tests

Review

Maybe @yaahc and/or @teor2345 . Not urgent.

Related Issues

Close #1484, close #1508, close #1632, close #1509 if merged.

Follow-Up Tasks

Make initial peers DNS resolution async #1613
Make listener DNS resolution non-blocking #1631
Interrupt handler does not work when a blocking task is running #1351
Windows state path message #1654

[oxarbitrage]

In a similar way we can do #1508 for a "LOCK file in use" hint.

I added this at 11cbfc7

Updating the original post.

[teor2345]

Can you also fix #1509 In this PR?

#1484 and #1509 should have similar hints, so I want to do them in the same PR.

[teor2345]

It might also be helpful to add an acceptance test that:

1. launches two Zebra instances with the same temporary directory and random port, and
2. makes sure that the output includes any one of these hints (it doesn't matter which one)

I added a random_port() function to the acceptance tests a few days ago - you can use it to pick a random port for this test's config.

[oxarbitrage]

I can't see how to reproduce #1509. For #1484 i can just open the port with some other program, for #1508 i can run 2 instances of zebrad in different ports.

For #1509 according to logs the error should be originated here https://github.com/ZcashFoundation/zebra/blob/main/zebrad/src/components/sync.rs#L280

[teor2345]

I can't see how to reproduce #1509. For #1484 i can just open the port with some other program, for #1508 i can run 2 instances of zebrad in different ports.

For #1509 according to logs the error should be originated here https://github.com/ZcashFoundation/zebra/blob/main/zebrad/src/components/sync.rs#L280

See this comment in #1484:

if you have zcashd occupying 8233 it just panics with zebra_network::peer::connection: e=buffered service failed: buffered service failed: Address already in use (os error 98)

Try disabling the metrics and tracing listeners, and just having a Zcash network protocol listener?

There are 3 different ports that can conflict:

1. metrics listener (Add a hint to the port conflict panic #1484)
2. tracing listener (Add a hint to the port conflict panic #1484)
3. Zcash network protocol listener (Add a hint to the "Address already in use" error #1509)

We need to cover all 3 cases in this PR.

[oxarbitrage]

If you have a zcashd running what you get with this PR is:

...
The application panicked (crashed).
Message:  Listener failed. Port already in use. Is another instance of zebrad or zcashd running in your local machine ? Consider changing the default port in the configuration file.
Location: /home/oxarbitrage/zebra/issue1484/zebra/zebra-network/src/peer_set/initialize.rs:218
...

[oxarbitrage]

I actually don't see #1484 referring to metrics or tracing endpoints. By the description it seems clear to me that the problem is at port 8233 which is the network port.

[teor2345]

I actually don't see #1484 referring to metrics or tracing endpoints. By the description it seems clear to me that the problem is at port 8233 which is the network port.

Yes, but any of those ports can conflict, so we need to add hints to all of them.

[oxarbitrage]

Yes, but any of those ports can conflict, so we need to add hints to all of them.

Makes sense, i will take care of this.

[oxarbitrage]

Added hints for tracing and metric endpoints port conflict in abfe4f6 and 73a74ef. When i saw the tracing one i noticed there was a hint as an error and i changed to a panic. I understand the application could continue without the tracing endpoint but it is not what the user will want. I think a panic is fine here but not totally sure.

[yaahc]

this looks great ^_^

[oxarbitrage]

Last changes looks good, thanks @teor2345 , looks like this one is finally ready.

CI failing at large sync tests which is unrelated here, all normal tests passing.

[teor2345]

CI failing at large sync tests which is unrelated here, all normal tests passing.

I updated #1651 to add the error message we saw in this CI run. Still Windows large sync tests, but at a slightly different stage of linking.

[teor2345]

I think we're good to go here.