Bug #93197 | MySQL logs error when performing TCP health checks | ||
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Submitted: | 14 Nov 2018 19:34 | Modified: | 7 May 2019 9:30 |
Reporter: | Daniele Lisi | Email Updates: | |
Status: | Won't fix | Impact on me: | |
Category: | MySQL Server: Connection Handling | Severity: | S3 (Non-critical) |
Version: | 5.7.24 | OS: | Linux |
Assigned to: | CPU Architecture: | x86 | |
Tags: | consul, health check, packets error, tcp |
[14 Nov 2018 19:34]
Daniele Lisi
[16 Nov 2018 16:51]
MySQL Verification Team
Hi, We do not have nor use that program named `consul`. Hence, should the usage of `nc` be enough or not ??? Thanks in advance.
[16 Nov 2018 16:58]
Daniele Lisi
Yes, 'nc' would be enough to reproduce the issue.
[19 Nov 2018 15:57]
MySQL Verification Team
Hi, Indeed, when I have run that `nc` command 100 times I got a plethora of : 8-11-19T15:55:03.493890Z 3 [Note] Got an error reading communication packets 2018-11-19T15:55:04.747845Z 4 [Note] Got an error reading communication packets 2018-11-19T15:55:06.217617Z 5 [Note] Got an error reading communication packets 2018-11-19T15:55:07.284145Z 6 [Note] Got an error reading communication packets 2018-11-19T15:55:09.131607Z 7 [Note] Got an error reading communication packets 2018-11-19T15:55:10.260825Z 8 [Note] Got an error reading communication packets 2018-11-19T15:55:11.292859Z 9 [Note] Got an error reading communication packets Verified as reported.
[7 May 2019 9:30]
Erlend Dahl
Posted by developer: Jens Even Blomsoy Not sure we can fix this in any way. Reason: In this bug, we are passing -z option to Netcat, which means Netcat should just scan for listening daemons, without sending any data to them. For every connection, server tries to read packets from the connection during handshake. In this case, we are not giving any data for the handshake to pass. Server tries to read packets, there are no packets. Hence error. You can actually verify this. Pass any other option to netcat which actually sends data and send the data. The error wont be logged.
[7 May 2019 13:11]
MySQL Verification Team
Erlend, Thank you very much for your diagnosis.