Forum Discussion
BOUABRE_343008
Nimbostratus
NimbostratusMonitor problem
Hello
I have a web application that has been inaccessible for some time. But when I change the monitor for an HTTP monitor (monitor by default), services are "OK".
What can be the cause of this problem?
version: BIG-IP 11.6.3.2 monitor(which is a problem): HEAD /jboss/CSS_keepalive.txt HTTP/1.0\r\n Connection: Close\r\n\r\n The monitor is working properly before.
-
tcpdump
10.55.X.X.80 > 10.X.X.X.40706: Flags [P.], cksum 0xdd52 (correct), seq 1:163, ack 63, win 114, options [nop,nop,TS val 950819840 ecr 1940015649], length 162: HTTP, length: 162
HTTP/1.1 400 Bad Request Date: Sun, 26 Aug 2018 00:29:00 GMT Server: Apache/2.2.15 (Red Hat) Connection: close Content-Type: text/html; charset=iso-8859-1 in slot1/tmm0 lis=
-curl -vk
GET / HTTP/1.1
User-Agent: curl/7.19.7 (x86_64-redhat-linux-gnu) libcurl/7.19.7 OpenSSL/1.0.1l zlib/1.2.3 libidn/0.6.5
Host: 10.55.X.X
Accept: */*
HTTP 1.0, assume close after body
HTTP/1.0 503 Service Unavailable
HTTP/1.0 connection set to keep alive!
Connection: Keep-Alive
Content-Length: 1281
Regards
Hi
Is your web server allowing http 1.0 request ? based on the output it certainty does not look http 1.0 is allowed on the webserver . can you test the below
curl --head --http1.0 and compare it against curl --head
jaikumar_f5MVP
Was your webserver recently upgraded. If yes, then there is high chance the monitor is broken. As you claim it was working before and now it has stopped, which questions what happened in the servers. I'd guess your webservers were upgraded and post that monitoring failed.
Also the error code 400 bad request logs when the request being sent is having syntax issues. Maybe your send string is having some issues. It could a space or it could be CR/LF anything. You have to figure that out.
I recently encountered this issue, check my thread.
KevinA_246454Cirrostratus
Hi
Is your web server allowing http 1.0 request ? based on the output it certainty does not look http 1.0 is allowed on the webserver . can you test the below
curl --head --http1.0 and compare it against curl --head
BOUABRE_343008Hello
Thank you for your answer, I think an update on the server broke the monitor. I have a 403 error that denies me access to the application
curl --head HTTP/1.1 403 Forbidden Date: Tue, 28 Aug 2018 22:35:29 GMT Server: Apache/2.2.15 (Red Hat) Connection: close Content-Type: text/html; charset=iso-8859-1
curl --head --http1.0 HTTP/1.1 403 Forbidden Date: Tue, 28 Aug 2018 22:34:46 GMT Server: Apache/2.2.15 (Red Hat) Connection: close Content-Type: text/html; charset=iso-8859-1
This error message may mean that you can not access a page because of a missing password.
Regards
- KevinA_246454
HI Thanks for the feedback, I see i made a typo in the curl request please can you run the below
curl --head --http1.0 curl --head
I must the /jboss uri path :)
- BOUABRE_343008
Hello
Please look
curl --head --http1.0 HTTP/1.1 200 OK Date: Thu, 30 Aug 2018 02:06:26 GMT Server: Apache/2.2.15 (Red Hat) Last-Modified: Wed, 15 Mar 2017 03:20:42 GMT ETag: "61fcb-3-54abc6deb5680" Accept-Ranges: bytes Content-Length: 3 Connection: close Content-Type: text/plain; charset=UTF-8
curl --head HTTP/1.1 200 OK Date: Thu, 30 Aug 2018 02:06:44 GMT Server: Apache/2.2.15 (Red Hat) Last-Modified: Wed, 15 Mar 2017 03:20:42 GMT ETag: "61fcb-3-54abc6deb5680" Accept-Ranges: bytes Content-Length: 3 Connection: close Content-Type: text/plain; charset=UTF-8
Regards
- Stanislas_Piro2
Cumulonimbus
Hi,
Can you change the monitor send string to
HEAD /jboss/CSS_keepalive.txt HTTP/1.0\r\nConnection: Close\r\n\r\nCan you try this command line
(echo -ne "HEAD /jboss/CSS_keepalive.txt HTTP/1.0\r\nConnection: Close\r\n\r\n"; cat) | nc 10.X.X.X 80