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Blue_whale's avatar
Blue_whale
Icon for Cirrocumulus rankCirrocumulus
Jun 11, 2020

F5 is not marking the pool member status as DOWN

Hi All ,   When the service on the member node 10.179.16.19 is DOWN, the F5 monitor is not marking the pool member status as offline .     When server team changes the receive string code to 50...
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  • cjunior's avatar
    cjunior
    Jun 16, 2020

    Hello,

    Probably the string "200" appears on head or body, while the string "200 OK" appears only on http response code status in headers.

    e.g.

    This output has "200 OK" on header and "200" on body.

    # curl -kv http://172.30.0.1/default.asp
*   Trying 172.30.0.1...
* Connected to 172.30.0.1 (172.30.0.1) port 80 (#0)
> GET /default.asp HTTP/1.1
> Host: 172.30.0.1
> User-Agent: curl/7.47.1
> Accept: */*
>
< HTTP/1.1 200 OK
< Cache-Control: private
< Content-Type: text/html
< Server: Microsoft-IIS/10.0
< Set-Cookie: ASPSESSIONIDCADABDAD=OPKBINHAKLGGIGHNPBCBEDGP; path=/
< Date: Tue, 16 Jun 2020 17:04:22 GMT
< Content-Length: 118
<
<html>
<head>
</head>
<body>
 200  is a number that matches 200
 2002 is a number that matches 200 as well
 </body>
</html>
* Connection #0 to host 172.30.0.1 left intact

    This other response header example, the HTTP code is 503 while content-length is 200 that matches your recv param.

    HTTP/1.1 503 Service Unavailable
Cache-Control: private
Content-Type: text/html
Content-Length: 200

    Regards.

     

Blue_whale's avatar
Blue_whale
Icon for Cirrocumulus rankCirrocumulus

Hi Cjunior ,

 

Thanks for your response .

 

Sorry I have corrected my question ,

 

Issue reported : When the service on the member node 10.179.16.19 is DOWN, the F5 monitor is not marking the pool member status as offline .

When server team changes the receive string code to 503 from 200 from the server end , pool member is not marked as DOWN ,

 

Action taken : We decided to change the monitor string to "200 OK" from 200 on the F5 ,it than worked correctly .

Meaning when server team now changed the string to 503 , monitor on the F5 marked pool member down .

 

 

So what is the issue here ? What is the difference with string 200 and "200 OK"

 

cjunior's avatar
cjunior
Icon for Nacreous rankNacreous
Jun 16, 2020

Hello,

Probably the string "200" appears on head or body, while the string "200 OK" appears only on http response code status in headers.

e.g.

This output has "200 OK" on header and "200" on body.

# curl -kv http://172.30.0.1/default.asp
*   Trying 172.30.0.1...
* Connected to 172.30.0.1 (172.30.0.1) port 80 (#0)
> GET /default.asp HTTP/1.1
> Host: 172.30.0.1
> User-Agent: curl/7.47.1
> Accept: */*
>
< HTTP/1.1 200 OK
< Cache-Control: private
< Content-Type: text/html
< Server: Microsoft-IIS/10.0
< Set-Cookie: ASPSESSIONIDCADABDAD=OPKBINHAKLGGIGHNPBCBEDGP; path=/
< Date: Tue, 16 Jun 2020 17:04:22 GMT
< Content-Length: 118
<
<html>
<head>
</head>
<body>
 200  is a number that matches 200
 2002 is a number that matches 200 as well
 </body>
</html>
* Connection #0 to host 172.30.0.1 left intact

This other response header example, the HTTP code is 503 while content-length is 200 that matches your recv param.

HTTP/1.1 503 Service Unavailable
Cache-Control: private
Content-Type: text/html
Content-Length: 200

Regards.