ISA Web proxy filter timeout

Posted on 2011-05-04
Last Modified: 2012-07-06

I am running an ISA 2006 SP1 server with Web proxy filter.
Occasionally, a request will come in through the proxy and the destination site would be down and unresponsive (in a sniff, it does not respond to three SYN requests).
This site is also configured as "Bypass" in the ISA configuration.

In this case, a 504 error would be returned to the originator after a very long period of time, I saw 63 seconds in one case. is there any way to set this timeout?

Question by:shootbox
    LVL 23

    Expert Comment

    by:Suliman Abu Kharroub
    Is there any errors on monitoring tab ?

    Author Comment

    Well yeah, the error is 504 and I will see it in the monitoring tab. other than that why would there be another error?
    LVL 23

    Expert Comment

    by:Suliman Abu Kharroub
    does it happen to all users for certain websites ? or for all website for certain users ? more info please..

    Accepted Solution

    Hi Sulimanw,

    "the destination site would be down and unresponsive (in a sniff, it does not respond to three SYN requests)."

    I will try to explain again:
    I am dealing with a site that is actually down, I have no complaints towards the website owner, nor do I care why his site is down.
    My internal users are making requests to this site, however I have configured this site to by Bypassed by ISA's web proxy filter.
    In this case, I don't seem to have any setting for a timeout of such request. ISA is taking a lot of time to close the connection and give up on it. like I said, in a sniff I can immediately see that the site does not respond to three SYN Requests, so why does ISA take so much time in closing the connection and returning an error?

    Author Closing Comment

    This is the solution.

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