Hi All, With 10.0.1 code, a health check that checks for http GET requests and receive "200 OK" passed with no problems. When the code was upgraded from 10.0.1 to 10.2.1, all servers that had this health check were marked down causing an unexpected outage. I run the same health check on the F5 CLI by doing telnet to port 80 on the server and sending the same GET request and I get a "200 OK" response. I am not sure what the problem is. I increased the timeout but the problem is not due to the timeout. Meena

Hi Meena, In 10.2.0, bigd behavior was modified to not append any \r\n's to the end of the monitor send string for HTTP, HTTPS and TCP. If you add two \r\n's to the end of the send string does the pool get marked up? See SOL10655 for details: sol10655: Change in Behavior: CR/LF characters appended to the HTTP monitor Send string http://support.f5.com/kb/en-us/solutions/public/10000/600/sol10655.html Aaron

Aaron, I played around with it adding and removing extra CR and LF but cannot bring up the pool. The only work around I have to bring up the pool and the web page is to remove the check for receive string. Tcpdump shows 200 OK string on the response and I have no idea why it fails. I modified the receive string to exactly match the case etc. The same monitor works fine for the same servers from Big-IP running 9.4.7 code. When I run the same GET request on the Big-IP CLI (Linux OS), it works fine. It is just the TMOS version 10.2.1 that is having issues. Meena

Can you post anonymized send and receive strings that were working in 9.4.7? Aaron

This is the monitor that works in 9.4.7 and 10.0.1 but does not in 10.2.1. GET / HTTP/1.1\r\nHost : 10.22.0.192\r\n and the receive string is 200 OK. GET /login.asp HTTP/1.1\r\nHost: 10.22.0.196\r\nConnection: Close\r\n and the receive string is 200 OK. I added extra and removed \r\n but nothing seems to work. Meena

Can you try this: GET /login.asp HTTP/1.1\r\nHost: 10.22.0.196\r\nConnection: Close\r\n\r\n And then start with a receive string of HTTP. If that works, then try 200 OK. If one or both don't work, you can try the steps outlined here to troubleshoot the issue: http://devcentral.f5.com/wiki/default.aspx/AdvDesignConfig/TroubleshootingLtmMonitors.html or here: http://support.f5.com/kb/en-us/solutions/public/12000/500/sol12531.html Aaron

health monitor that worked in 10.0.1 failed with 10.2.1

hoolio
Cirrostratus
May 09, 2011
Hi Meena,

In 10.2.0, bigd behavior was modified to not append any \r\n's to the end of the monitor send string for HTTP, HTTPS and TCP. If you add two \r\n's to the end of the send string does the pool get marked up?

See SOL10655 for details:

sol10655: Change in Behavior: CR/LF characters appended to the HTTP monitor Send string

http://support.f5.com/kb/en-us/solutions/public/10000/600/sol10655.html

Aaron
meena_60183
Nimbostratus
May 10, 2011
Aaron,

I played around with it adding and removing extra CR and LF but cannot bring up the pool. The only work around I have to bring up the pool and the web page is to remove the check for receive string. Tcpdump shows 200 OK string on the response and I have no idea why it fails. I modified the receive string to exactly match the case etc.

The same monitor works fine for the same servers from Big-IP running 9.4.7 code. When I run the same GET request on the Big-IP CLI (Linux OS), it works fine. It is just the TMOS version 10.2.1 that is having issues.

Meena
hoolio
Cirrostratus
May 10, 2011
Can you post anonymized send and receive strings that were working in 9.4.7?

Aaron
meena_60183
Nimbostratus
May 10, 2011
This is the monitor that works in 9.4.7 and 10.0.1 but does not in 10.2.1.

GET / HTTP/1.1\r\nHost : 10.22.0.192\r\n and the receive string is 200 OK.

GET /login.asp HTTP/1.1\r\nHost: 10.22.0.196\r\nConnection: Close\r\n and the receive string is 200 OK.

I added extra and removed \r\n but nothing seems to work.

Meena
hoolio
Cirrostratus
May 10, 2011
Can you try this:

GET /login.asp HTTP/1.1\r\nHost: 10.22.0.196\r\nConnection: Close\r\n\r\n

And then start with a receive string of HTTP. If that works, then try 200 OK. If one or both don't work, you can try the steps outlined here to troubleshoot the issue:

http://devcentral.f5.com/wiki/default.aspx/AdvDesignConfig/TroubleshootingLtmMonitors.html

or here:

http://support.f5.com/kb/en-us/solutions/public/12000/500/sol12531.html

Aaron
meena_60183
Nimbostratus
May 10, 2011
Ok. I tried this and it is working.

~~GET /login.asp HTTP/1.1\r\nHost: 10.22.0.196\r\n\r\nConnection: Close\r\n~~

~~and the receive string is 200 OK. Thanks Aaron.~~

~~Meena~~
hoolio
Cirrostratus
May 10, 2011
That wouldn't be a valid HTTP request as the double \r\n would terminate the request and then you have another HTTP header appended. Can you try it like this:

GET /login.asp HTTP/1.1\r\nHost: 10.22.0.196\r\n\r\n

with a receive string of 200 OK?

Aaron
meena_60183
Nimbostratus
May 10, 2011
Yes. I tried that and it is also working.
Sujan_88694
Nimbostratus
Jun 24, 2011
Hi Meena & Other experts

I have been using the below string in 10.1 for http service monitoring. But on 10.2 its not working. Any idea how i should be modifying the string?

GET /CAI3G1.1/services/CAI3G1.1 HTTP/1.0\r\n

and no receive string 200 OK. used in 10.1.

I have tried the below and receive string as 200 OK. still not working.

GET /CAI3G1.1/services/CAI3G1.1 HTTP/1.0\r\n \r\n

any help would be much appreciated.

Thanks a lot in advance.

//Sujan
dubdub
Nimbostratus
Jun 24, 2011
Hi Sujan,

Looks like you might have a space character between your two \r\n sequences? Can you remove that and try again?

Thanks,

Jen