The HTTP checks configured in the service formerly known as "watchmouse" are alerting.
They say we are issuing 400 responses to their probes:
Server Response: HTTP/1.1 400 Bad Request
Description
Description
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I cannot find any indication that the 400s are originating from our servers either in webrequest log or turnilo.
I have temporarily disabled the alerts until this can be looked into further or other indications of issues on our systems are indicated.
Comment Actions
In the checks definition, under "Advanced" -> "Custom HTTP request headers" we used to specify a header with quotes, which was passed verbatim by CA App Synthetic Monitor.
Quotes removed, checks are now green. It seems that between Varnish 5 and Varnish 6 something changed in the handling of silly request headers:
Varnish 6:
$ printf 'GET /wiki/Main_Page HTTP/1.1\r\nHost: en.wikipedia.org\r\nX-Forwarded-Proto: https\r\n"Cookie: prova"\r\n\r\n' | nc localhost 80 | head -1 HTTP/1.1 400 Bad Request
Varnish 5:
$ printf 'GET /wiki/Main_Page HTTP/1.1\r\nHost: en.wikipedia.org\r\nX-Forwarded-Proto: https\r\n"Cookie: prova"\r\n\r\n' | nc localhost 80 | head -1 HTTP/1.1 200 OK