Forum Discussion

trx's avatar
trx
Sep 17, 2011

health monitor problem with 2 pools

Hello All,

 

 

 

I'm having a problem with health monitors on 2 pools. Below is the setup/description:

 

 

 

1) 1 VS

 

2) Uses IRules to determine if it goes to pool A (IIS on Server1) or pool B (apache on Server1)

 

3) Health monitor created to monitor APACHE:

 

GET /servername.txt HTTP/1.1\r\nHost: 192.168.11.150\r\nConnection: Close\r\n

 

4) This health monitor is applied to both IIS and APACHE pool

 

5) When turning off APACHE service, ONLY the APACHE pool is marked DOWN, but the IIS pool is still marked UP.

 

 

 

Why is that the case? One would assume it would mark them both down, as the health monitor specifies to look at the APACHE IP.

 

 

 

Thoughts oh why this is happening or how to resolve this issue?

 

 

 

Thanks in advance.

 

 

 

Regards,

 

TRX

 

config
design
  • nitass's avatar
    nitass
    Icon for Employee rankEmployee
    Sep 17, 2011
    GET /servername.txt HTTP/1.1\r\nHost: 192.168.11.150\r\nConnection: Close\r\n

     

    i understand we don't need to specific ip address in host header i.e. leaving it just blank.

     

     

    additionally, is a number of CR/LF in send string correct?

     

     

    sol2167: Constructing HTTP requests for use with the HTTP or HTTPS application health monitor

     

    http://support.f5.com/kb/en-us/solutions/public/2000/100/sol2167.html

     

     

    5) When turning off APACHE service, ONLY the APACHE pool is marked DOWN, but the IIS pool is still marked UP.

     

    if service is shuted down, monitor should mark pool down.

     

    were u able to telnet to port 80 after turning it off?

     

  • Hamish's avatar
    Hamish
    Icon for Cirrocumulus rankCirrocumulus
    Sep 23, 2011
    You seem to be missing the extra \r\n on the end of the query... HTTP/1.10 and HTTP/1.0 require a blank line at the end of the query so the server knows that you've finished sending it.

     

     

    Later versions of LTM no longer prepend an automatic \r\n to the end of the query string. You may be hitting this issue...

     

     

    Why it would work with IIS I'm not sure though...

     

     

    H