Helth Monitor http HTTP/1.1 400 Bad Request

Question

Hello all, &nbsp;I have built the following monitor:GET /lexsoft/sgbplus/#default:0 HTTP/1.1
Host: test.test
Connection: Close

&nbsp;as return code I expect a 200 OK but get a 400 back&nbsp;HTTP/1.1 400 Bad RequestDate: Wed, 14 Jul 2021 05:32:30 GMTServer: Apache/2.4.6 (Red Hat Enterprise Linux)Content-Length: 226Connection: closeContent-Type: text/html; charset=iso-8859-1&nbsp;&lt;!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN"&gt;&lt;html&gt;&lt;head&gt;&lt;title&gt;400 Bad Request&lt;/title&gt;&lt;/head&gt;&lt;body&gt;&lt;h1&gt;Bad Request&lt;/h1&gt;&lt;p&gt;Your browser sent a request that this server could not understand.&lt;br /&gt;&lt;/p&gt;&lt;/body&gt;&lt;/html&gt;&nbsp;If I do the following CURL command I get my 200 backcurl -v http://test.test/lexsoft/sgbplus/#default:0&nbsp;*&nbsp;&nbsp;Trying test.test...* Connected to test.test (x.y) port 80 (#0)&gt; GET /lexsoft/sgbplus/ HTTP/1.1&gt; Host: test.test&gt; User-Agent: curl/7.47.1&gt; Accept: */*&gt; &lt; HTTP/1.1 200 OK&nbsp;What should my monitor look like to get the desired result?&nbsp;&nbsp;Thanks for your help&nbsp;&nbsp;&nbsp;

samir_kumar_jha · Answer

Can you please remove "#default:0" from URI of monitor string and give try.i.e&nbsp;GET /lexsoft/sgbplus/ HTTP/1.1
Host: test.test
Connection: Close

&nbsp;

daniel_wolf · Answer

Additionally to &nbsp;suggestion, take a look at RFC3986: https://datatracker.ietf.org/doc/html/rfc3986#section-3.5Notice the # in the URL? It is called a Fragment, typically used to identify a portion of a html document.&nbsp;This is another example: https://support.f5.com/csp/article/K12783074#p2It is linking to a headline in the solution page.&nbsp;I am not exactly sure how health monitors handle the hash mark... Might be your issue.

andre-germany · Answer

Have times "#default:0" that deleted.But has not led to any new result &nbsp;What is interesting, with two servers that have been in the pool for a while, the check to works as described above. Only with the two new servers I always get the answer 400 back&nbsp;&nbsp; The F5 description is about SSL.For me it is pure HTTP traffic

daniel_wolf · Answer

&nbsp;I have choosen the link to the F5 solution randomly. I wanted to show you what the hash mark (#) does in a link. The is linking to a specific section in the html document you get from the server.&nbsp;In your browser, when you open http://www.mysite.com/subsite1 - you will go to the top of subsite one. When you open http://www.mysite.com/subsite1#headline2 - you will jump to headline 2 of subsite1.I am not sure how the monitors of the BIG-IP handle the #.

andre-germany · Answer

I tried a little more and deleted the "Connection: Close" now I get a 200 back

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