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HTTP sensor problems...



We have a client with three websites located in the same root (one for USA, one for Canada English [CA=EN] and one for Canada French [CA-FR]). In our IIS 7.5, we have two sites defined (one for the USA URL, the other for the Canada URL). We've never had a problem until IIS 7.5 but periodically, both the CA-EN and the CA-FR HTTP sensors go down and I'm trying to figure out why. One thought was that there might be a conflict with the two defined sites sharing the same root, but I don't think that's it. The Canada sites have virtually no traffic in comparison to the USA ones and they both have their own AppPools, but the Canada sites seem to still get script time-outs on certain low-level Classic ASP pages. Does anyone have any thoughts on what I should investigate next? (I can also post any data that may help) This has been happening since we switched to this new server, so I'm positive it's something in the configuration.

http-sensor iis windows-2008-r2-sp1

Created on May 6, 2013 5:58:24 PM

3 Replies



When these HTTP sensors go down, do they give a specific error or is there anything in the logs that you can tell me specifically?

Also. have you checked the web server logs to see if they give any indication as to why there may not be a value returned when PRTG is connecting?

Created on May 7, 2013 12:23:48 PM by  Greg Campion [Paessler Support]



I'm pasting what I get normally:

Sensor ADS CA-EN HTTP Sensor (HTTP) Status Down () Date/Time 07.05.2013 02:47:00 (Eastern Standard Time) Last Result Last Message Read timed out. Probe SocialHippo Client Web Sites Group ADS Web Server Device ADS CA-EN Website (ads-pipecanada.ca) Last Scan 07.05.2013 02:45:44 [151 s ago] Last Up 07.05.2013 02:42:44 [5 m 30 s ago] Last Down 07.05.2013 02:45:44 [151 s ago] Uptime/Downtime Up: 92.7291% [11 d 14 h] Down: 7.2709% [21 h 51 m 33 s] Cumulated since: 24.04.2013 14:03:49 Settings Interval: 60 sec URL: http://www.ads-pipecanada.ca/ca_en/Sensors/webtest.asp Location Sensor History 07.05.2013 02:45:44 Down, Read timed out. 07.05.2013 02:44:44 Warning, Read timed out. 07.05.2013 02:41:55 Up, 11,034 msec 07.05.2013 02:40:44 Down, Read timed out. 07.05.2013 02:39:44 Warning, Read timed out. 07.05.2013 01:01:05 Up, 193 msec 07.05.2013 01:01:05 Warning, Connection timed out (socket error # 10060) 06.05.2013 12:35:44 Notification Info, State Trigger activated (Sensor/Source/ID: 2079/0/2) 06.05.2013 12:35:44 Notification Info, State Trigger activated (Sensor/Source/ID: 2079/0/1) 06.05.2013 12:35:44 Notification Info, State Trigger activated (Sensor/Source/ID: 2079/1/1)

They mainly say "Read timed out". Or is there a better way for you to see this information?

Created on May 7, 2013 2:33:49 PM



I tested out your website with a sensor that I created here and at first it was working but then it went into a down state just like yours did but when I tried to access the page from my computer, the page wouldn't load either so technically the sensor is reporting correctly in my case anyways.

When this is reporting down, can you check to see if you are able to access the site from the probe computer? Also, can you check the logs for this web server to see if there is something going on with the server? It may be that it's rejecting these requests.

Created on May 8, 2013 12:22:32 PM by  Greg Campion [Paessler Support]

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