Receive String problem

Check out this support article from ask.f5.com

 

 

https://support.f5.com/kb/en-us/solutions/public/3000/200/sol3224.html

 

 

CB

 

There needs to be two carriage return - line feeds at the end of a GET request. The monitoring daemon appends one for you.

 

 

If you use HTTP 1.1, you can tell the server that LTM isn't going to try to re-use the TCP connection:

 

 

GET / HTTP/1.1\r\nConnection: Close\r\nHost: \r\n

 

 

You can test this using netcat from the command line of the BIG-IP:

 

 

echo -e "GET / HTTP/1.1\r\nConnection: Close\r\nHost: \r\n\r\n" | nc 1.1.1.1 80

 

 

Replace 1.1.1.1 with the actual IP address of the server you want to test to.

 

 

Aaron

Thanks for help.

 

I checked the https://support.f5.com/kb/en-us/solutions/public/3000/200/sol3224.html solution before, but I don't think that's it.

 

 

I used GET / HTTP/1.1\r\nConnection: Close\r\nHost: \r\n, GET / HTTP/1.0\r\nConnection: Close\r\nHost: \r\n and many others.

 

 

I tested it with nc (really good idea) and everything seems to be responding well, but I still have the same problem.

 

 

It seems that my LTMs are checking only for 80 lines of received code (my file had 363 and I was checking a string on the very bottom).

 

Everything before line 80 is making the monitor go up, after line 80 including line 81 is making the monitor to go down.

 

 

I'm fine with it.

 

I can pick something from line 27, but did you have any similar experience with it before?

Hi,

 

 

Take a look at this post for details on this (Click here).

 

 

Aaron

Solved.

 

 

Receiving string of the http monitor build into the F5s is accepting only 5,120 bytes into an HTTP.

 

In my example it was about 80 lines of the code.

 

 

SOL3451 saved the day!

 

 

I appreciate your help!

 

 

M

Hi Whats should be the receive string for the below - output to web server - I have tried almost everything doesnt work, maybe my receive string syntax is wrong. I am just new at this...please help

 

 

[root@lab-3400:Active] config echo -e "GET / HTTP/1.1\r\nConnection: Close\r\nHost: \r\n\r\n" | nc 1.1.1.1 80

 

HTTP/1.1 200 OK

 

Content-Length: 1337

 

Content-Type: text/html

 

Content-Location: http:///iisstart.htm

 

Last-Modified: Mon, 17 Nov 2008 00:29:39 GMT

 

Accept-Ranges: bytes

 

ETag: "a0908a934b48c91:322"

 

Server: Microsoft-IIS/6.0

 

Date: Wed, 29 Jul 2009 07:18:14 GMT

 

Connection: close

 

 

 

 

 

 

 

 

You are on DMZ WEB SERVER

 

 

 

 

 

 

 

 

Under Construction This is the DMZ WEb Server Please try this site again later. If you still experience the problem, try contacting the Web site administrator. If you are the Web site administrator and feel you have received this message in error, please see "Enabling and Disabling Dynamic Content" in IIS Help. To access IIS Help Click Start, and then click Run. In the Open text box, type inetmgr. IIS Manager appears. From the Help menu, click Help Topics. Click Internet Information Services.

 

 

 

 

 

[root@lab-3400:Active] config

from what i understand is receive string could be anything in the html page

You could set the receive string to '200 OK' without the quotes to look for a 200 response. However, it looks like you have host headers set up on your web server and the request is being handled by the default web application instance--not a specific web application. You might want to set a host header in the send string which matches the host header filters configured on IIS so you test the actual web application.

 

 

Aaron

thanks for the reply, yes! 200 ok works well. I was wandering whether i can search for the String "DMZ" in the page. But when i use DMZ in the receive string web server is marked down.

 

If DMZ is found in the first 5120 bytes of the response, the member should get marked up. The response you posted is well under 5k, so that should work. If you run tcpdump do you see DMZ in the response? Is the Content-Length header under 5120 bytes? If so, and the monitor is still marking the pool member down, you might try enabling bigd debug using 'b db bigd.debug enable / disable'. The output is logged to /var/log/bigdlog.

 

 

Aaron