Issue with web responses from IIS
Hi Experts,
Hopefully you can help with a very bizarre issue
We noticed an issue with what we originally thought was the fault of our load balancers, where the site would go down, and be marked down by the LB, but when you attempt to browse directly to the server itself, the page would return.
A bit of investigation later, it appears to be a local problem on the web servers itself. Monitoring using wireshark, we could see the LB making the a health check (using a GET request to the URL), and the server delaying its response for an extended time, causing the health check to fail.
However, new requests coming from other IP's the web server responded to immediately
Does anyone know why this may occur?
The servers in question are Windows 2016 x64
Hopefully you can help with a very bizarre issue
We noticed an issue with what we originally thought was the fault of our load balancers, where the site would go down, and be marked down by the LB, but when you attempt to browse directly to the server itself, the page would return.
A bit of investigation later, it appears to be a local problem on the web servers itself. Monitoring using wireshark, we could see the LB making the a health check (using a GET request to the URL), and the server delaying its response for an extended time, causing the health check to fail.
However, new requests coming from other IP's the web server responded to immediately
Does anyone know why this may occur?
The servers in question are Windows 2016 x64
ASKER
Hi Dan,
Its a kemp, and its using a GET request for a URL on http. As long it brings back the page it considers it up
The check interval is 17 secs, connection timeout 6 and retry count 2
https://support.kemptechnologies.com/hc/en-us/articles/202214518-health-checking
Its a kemp, and its using a GET request for a URL on http. As long it brings back the page it considers it up
The check interval is 17 secs, connection timeout 6 and retry count 2
https://support.kemptechnologies.com/hc/en-us/articles/202214518-health-checking
Hopefully you have http logging enabled in IIS (with all fields selected), if so, when you look in the logs for the hit to your healthcheck URL, what is the time-taken field recording? Is it taking more than 6 seconds (6000 in time-taken) to service the http request?
Can you post a screen shot of the whole heath check rule?
Dan
Can you post a screen shot of the whole heath check rule?
Dan
Also, is the health check setup to hit the server's IP address or the FQDN of the server being checked? How are IP Addresses in IIS bound to the websites on the IIS Server?
Dan
Dan
ASKER
This might be an issue with our Load balancers after all, as the plot has thickened. Their support is now investigating so we'll see what happens
OK, but can you post any of the info from above?
Dan
Dan
Any feedback?
Dan
Dan
Is this still an issue?
Dan
Dan
Can the question be closed?
Dan
Dan
Any additional info for this question?
Dan
Dan
This question needs an answer!
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How is the health check setup? What is the health check process hitting to verify the server is up?
Dan