[MXS-4148] Log warning if reverse name resolution takes significant time Created: 2022-05-31 Updated: 2022-07-29 Resolved: 2022-07-11 |
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| Status: | Closed |
| Project: | MariaDB MaxScale |
| Component/s: | mariadbclient |
| Affects Version/s: | 2.5.16, 6.3.1 |
| Fix Version/s: | 2.5.22, 6.4.1 |
| Type: | Bug | Priority: | Major |
| Reporter: | Maria M Pflaum | Assignee: | Esa Korhonen |
| Resolution: | Fixed | Votes: | 0 |
| Labels: | None | ||
| Sprint: | MXS-SPRINT-159, MXS-SPRINT-160 |
| Description |
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Currently it is difficult to diagnose the Maxscale stall due to reverse DNS lookups. Customer would like skip_name_resolve default value to be set to true. When Slow reverse DNS lookups during authentication cause MaxScale to stall, the log output does not give an indication as to what is happening. Is it possible to add something to the log that indicates starting reverse dns lookup, and ending reverse dns lookup? And/or checking the amount of time that takes and possibly suggesting setting skip_name_resolve to be set to true. 2022-05-25 16:00:08 info : (391) [MariaDBProtocol] Client 'my_user'@'::ffff:10.180.66.24' is attempting a COM_CHANGE_USER to 'rw_user'. |
| Comments |
| Comment by markus makela [ 2022-06-01 ] |
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MariaDB by default has skip-name-resolve disabled so we want to have the same default for MaxScale as well. We could defnitely add some info level logging about how long name lookups take place. |
| Comment by Esa Korhonen [ 2022-06-20 ] |
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This is a bit weird in the sense that customers can avoid the name resolution just by avoiding user accounts with hostname-patterns. Using `skip-name-resolve` in effect disables such accounts anyway so the end effect is the same. Still, a log message which logs name resolves which take too long (e.g. 1 second or more) is simple to add. For which version is this required? |