[MDEV-24181] intermittent connection error Created: 2020-11-10  Updated: 2024-02-07

Status: Needs Feedback
Project: MariaDB Server
Component/s: None
Affects Version/s: 10.2.19, 10.2.27
Fix Version/s: 10.4, 10.5, 10.6, 10.11, 11.0, 11.1, 11.2, 11.3

Type: Bug Priority: Critical
Reporter: Allen Lee (Inactive) Assignee: Rob Schwyzer
Resolution: Unresolved Votes: 0
Labels: None
Environment:

Deployment: Physical Server, On Premise
Platform: CentOS

Issue Links:
Relates

 Description   

Customer reported intermittent connection error after moving server to haproxy/keepalived environment. However, after eliminating haproxy/keepalived, direct connection to server with mariadb client also showed the intermittent connection error(95% rate) as blow:

user@xxx:~$ while [ 1 ]; do mysql -h xxx mysql -ssss -e "select now(), @@hostname"; done
 
Error message : ERROR 1130 (HY000): Host 'xxx' is not allowed to connect to this MariaDB server

Customer also shared a couple more test results as below:

On host xxx:
 
mysql -h xxx -P 3307 -- errors seen
 
mysql -h localhost -P 3307 -- no errors
 
mysql -h 127.0.0.1 -P 3307 -- errors seen
 
mysql -h xxx.xx.xxx.xx -P 3307 -- errors seen (actual IP address)

And then, they did some upgrade to some of their servers and found that some version still shows the same connection errors.

* xxx/ yyy (upgraded to MariaDB 10.2.25) - do not have an issue anymore, not reproducible
 
* xxx / yyy
 
with MariaDB 10.2.19 - had the same error
 
with MariaDB 10.2.27 - still see the same error



 Comments   
Comment by Oleksandr Byelkin [ 2024-01-02 ]

des server has something like https://mariadb.com/kb/en/mariadb-maxscale-6-throttle/ set?

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