Note to Validators, Relayers, and constructors of IBC-enabled chains

[faddat]

Oct 13 20:01:31 archive hermes[1023361]:    0: GRPC call return error status status: InvalidArgument, message: "failed to execute message; message index: 0: cannot update client with ID 07-tendermint-73: failed to verify header: invalid header: new header has a time from the future 2021-10-13 18:01:25.05566312 +0000 UTC (now: 2021-10-13 18:01:18.875105001 +0000 UTC; max clock drift: 5s): invalid request", details: [], metadata: MetadataMap { headers: {"content-type": "application/grpc"} }

That there is chain A, rejecting the light client proof of chain B.

It is doing so because the time is wrong.

The resolution is fairly simple:

100% of validators should

systemctl enable systemd-timesyncd
systemctl start systemd-timesyncd

[jtieri]

Open issues in other repos that appear to describe this same issue:
cosmos/cosmos-sdk#10429
informalsystems/hermes#1445

[faddat]

Hey I should go a layer deeper: I was playing with the shared security demo and you know what happened?

I got this error, with two blockchains, on the same laptop. So the problem is not restricted to time alone

[crodriguezvega]

Thanks for bringing attention to this problem, @faddat. However, we think that there is nothing for ibc-go to do about this. We think that it would be valuable to add this information in a troubleshooting guide for validators/relayers and/or mention this in the validators-verified, relayers-verified or node-operators Discord channels.

Closing it for now.