Nagios Support Forum

In our application log, we're getting this error every check

2023-06-08 16:37:47,645 WARN [ajp-nio-10.20.30.40-9582-exec-3 ] [BrowserCheck:42] ( ) Unsupported browser detected: check_http/v2.3.3 (nagios-plugins 2.3.3) : Browser name = HTTP nagios plugin , Browser Version = VersionNumber [groups=[, , ], extension=v2.3.3]
2023-06-08 16:42:46,875 WARN [ajp-nio-10.20.30.40-9582-exec-3 ] [BrowserCheck:42] ( ) Unsupported browser detected: check_http/v2.3.3 (nagios-plugins 2.3.3) : Browser name = HTTP nagios plugin , Browser Version = VersionNumber [groups=[, , ], extension=v2.3.3]
2023-06-08 16:47:44,727 WARN [ajp-nio-10.20.30.40-9582-exec-4 ] [BrowserCheck:42] ( ) Unsupported browser detected: check_http/v2.3.3 (nagios-plugins 2.3.3) : Browser name = HTTP nagios plugin , Browser Version = VersionNumber [groups=[, , ], extension=v2.3.3]
2023-06-08 16:52:42,770 WARN [ajp-nio-10.20.30.40-exec-7 ] [BrowserCheck:42] ( ) Unsupported browser detected: check_http/v2.3.3 (nagios-plugins 2.3.3) : Browser name = HTTP nagios plugin , Browser Version = VersionNumber [groups=[, , ], extension=v2.3.3]

what is really odd is that 10.20.30.40 is not in our nagios anywhere.
I beleive we're using the same nrpe/agent version for all boxes.

You might want to find the service that's doing the check and read it and check_http -h output.