Error Code 502 Proxy Error Web Filter
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a proxy server. The problem is typically caused for one of two reasons: 1 – The Internet Security and Acceleration (ISA) is configured 502 proxy error web service to throw a proxy error to help guard against external or internally-based Internet 502 proxy error apache threats, and 2- The client or server computers are misconfigured or using outdated software. What is a 502 Proxy Error? 502 proxy error dns lookup failure A 502 proxy error is typically thrown in the HTTP cycle. When the error occurs, a server (does not have to be a Web server) is filling a role similar to a proxy 502 proxy error apache error reading from remote server or a gateway server. When a client computer sends an HTTP request (typically a web browser, but can be any software application that is capable of making an HTTP request), it will pass through the server in order to obtain access to the desired URL. The proxy or gateway subsequently receives a 502 error, or invalid response, from the server located “upstream” in the attempt
502 Proxy Error Reason Error Reading From Remote Server
to fulfill the client request. The majority of the time the error is thrown, the upstream server is functioning appropriately. The proxy or gateway and upstream servers just cannot agree on the appropriate protocol for exchanging the information requested in the original client HTTP request. In many of these cases, either the proxy or upstream server are not configured correctly or are running incompatible software. Why Does a 502 Proxy Error Get Thrown? During a typical web browsing session, the following is an example of the classic HTTP cycle when a client computer and web server are communicating: Client Computer: The IP address of the desired website will be obtained from the URL of the site from the DNS server. Client Computer: The computer obtains an IP socket connection to the desired IP address and then sends an HTTP data stream through the IP address. Web Server: HTTP data is sent back to the client computer in response to the original HTTP request. The HTTP response will include status codes and other useful information for the client computer. Client Computer: If there is an error in the client’s request or server’s ability to respond, th
Home Sophos UTM 9 Sophos XG Firewall Web 502 proxy error apache reverse proxy Appliance General Malware [Beta] Malware Course Sophos Intercept X Sophos Wireless Knowledge Base http://www.tech-faq.com/502-proxy-error.html Blog Sophos UTM 9 Web Protection: Web Filtering… Error code 502 UTM 9 Release Notes UTM Wiki Knowledge Base Sub-Groups Cancel This group requires membership https://community.sophos.com/products/unified-threat-management/f/web-protection-web-filtering-application-visibility-control/43888/error-code-502 for participation - click to join Thread Info State Not Answered Date Onah Date 22 Dec 2008 5:28 PM Replies 4 replies Subscribers 2 subscribers Views 340 views English Suggested Have a cool product idea or improvement? We'd love to hear about it! Click here to go to the product suggestion community Error code 502 Hi, SinceI'veupgradedtheASG320tov7.304I'mhavingtroublewithsomespecificwebs.Theerrormessageis:Connectiontoservertimedout. Ithappenswithurl'sthatsusesanspecificport.I'veaddedthisporttothelistofallowedtargetservicesandtheurlisallowedinthewebsecurityexceptions. Anyideas? I'vefoundthisatthelogs(it'sanexampleithappenswithdifferenturl's): 2008:12:22-17:02:17(none)httpproxy[3903]:id="0002"severity="info"sys="SecureWeb"sub="http"name="webrequestblocked"action="block"method="GET"srcip="10.100.24.24"user=""statuscode="502"cached="0"profile="profile_0"filteraction="action_REF_DefaultHTTPCFFAction"size="0"time="62152ms"request="0x972d9890"url="csi.ha.gva.es:8888/.../lista_mod_046.htm"error="Connectiontoservertimedout" 2008:12:22-17:02:22(none)httpproxy[3903]:id="0002"severity="info"sys="SecureWeb"sub="http"name="webrequestblocked"action="block"method="GET"srcip="10.100.24.24"user=""statuscode="502"cached="0"profile="profile_0"filteraction="action_REF_DefaultHTTPCFFAction"size="2233"time="61378ms"request="0x9467f568"url="csi.ha.gva.es:8888/.../lista_mod_046.htm"error="Connectiontoservertimedout" 2008:12:22-17:03:32(none)httpproxy[3903]:id="0002"severity="info"sys="SecureWeb"sub="http"name="webrequestblocked"action="block"method="GET"srcip="10.100.24.24"user=""statuscode="502"cached="0"profile="profile_0"filteraction="action_REF_DefaultHTTPCFFAction"size="2233"time="61641ms"request="0x99cb6770"url="csi.ha.gva.es:8888/.../lista_mod_046.htm"error="Connectiontoservertimedout" 2008:12:22-17:04:38(none)httpproxy[3903]:id="0002"severity="info"sys="SecureWeb"sub="http"name="webrequestblocked"action="block"method="GET"srcip="10.100.24.24"user=""statuscode="502"cached="0"profile="profile_0"filteraction="action_REF_DefaultHTTPCFFAction"size="2211"time="64513ms"request="0x99cb6770"url="csi.ha.gva.es:8888/favicon.ico"error="Connectiontoservertimedout" Cancel Jack Daniel 0 22 Dec 2008 7:34 PM Itmaybeacomponentofthesitedoesnotproxywell,haveyoutriedaddingthesitetothetransparentmodeskiplist(ifintransparen
were unaccessable and displaying Error Code: 502 Proxy Error. The data is invalid. (13) Source: web filter http://www.alexheer.co.uk/it-blog/tmg-2010-error-code-502-proxy-error-the-data-is-invalid-13 TMG by default is set to compress all HTTP responses. On this occassion the destinations web server is sending responses back in chunks which is a common thing and http://www.isaserver.org/blogs/shinder/news/isa-server-2004-blocks-requests-that-include-the-accept-encoding-http-header-when-a-forward-proxy-is-used-679.html if configured correctly does not cause any issues. However TMG's HTTP compression is seeing these chunks as seperate requests and cannot piece them together (search Chunked Transfer Encoding for more 502 proxy information).TMG is functioning correctly! The issue is most likley that thedesitnation web servers HTTP headers are incorrectly configured. I would attempt to contact the sitesweb administrator and point them in the directionof checkingtheir sites Transfer-Encoding header is 'chunked'. If you need to get round this error, you can either bypass TMG or disable HTTP compression on TMG.To do this, open 502 proxy error TMG > Web Access Policy. Under Web Access Settings, click 'HTTP Compression' and deselect 'Enable HTTP compression'.Though not ideal, you will now be able to access the site(s). 1 Comment Swingers New Mexico link 27/9/2013 09:58:54 pm Your blog looked so simple to design that I decided to create one, thanks! Reply Leave a Reply. Author Alex Heer Archives August 2016 June 2016 May 2016 March 2016 February 2016 October 2015 September 2015 August 2015 July 2015 April 2015 March 2015 January 2015 December 2014 September 2014 July 2014 June 2014 May 2014 April 2014 March 2014 February 2014 January 2014 December 2013 November 2013 October 2013 September 2013 August 2013 July 2013 June 2013 May 2013 April 2013 March 2013 February 2013 January 2013 Categories All Active Directory Awards Certification Cyber Dpm Exchange General Life Group Policy Home Computing Hyper V IIS Mcafee Microsoft Office Mimecast Networking Powershell Rds Security Server 2008 R2 Server 2012 Shoretel Social Media Sql Tmg Virtual Machines RSS Feed Create a free website Powered by Create your own free website Sta
15 Aug. 2008 / Last Updated on 15 Aug. 2008] Dall Ball, on the ISAserver.org mailing list shared an interesting problem. He noted that after installing ISA 2006 SP1, his users were starting to see errors that they hadn't seen before. The error returned to the users' browsers was: Error Code: 502 Proxy Error. The request is not supported. (50) It seemed like a pretty mysterious problem to me, even after checking a few lines of log files information provided by Dan. But then Dan did a packet trace on the connection and sent to Jim Harrison. Jim read the capture and said: Do you have compression disabled? If so, have a peek at the script in http://support.microsoft.com/?id=927263. This script is supported for ISA 2006 after SP1. This is a problem I wasn't aware of! You might have the same problem as Dan if the following is true: On a server that is running Microsoft Internet Security and Acceleration (ISA) Server 2004 with Service Pack 2, you disable the following two Web filters: Compression Filter Caching Compressed Content Filter After you do this, ISA Server 2004 blocks requests that include the Accept-Encoding HTTP header when a forward proxy is used. These Web filters were introduced in ISA Server 2004 Service Pack 2. You might disable these Web filters because of program compatibility problems that involve some Web servers. So, if you're seeing random 502 proxy errors with the request not being supported (50), then you should run the script found at http://support.microsoft.com/kb/927263 UPDATE: More information on this issue from Jim Harrison: "When compression is disabled, ISA will strip off the “Accept-encoding” header that the client sends. This is done to prevent the web site sending compressed responses because ISA can’t apply HTTP body inspection to it. In this case (and several others, it seems), the web site sends compressed content anyway (it’s a Sun server; waddayexpect?). Since ISA knows it can’t process compressed HTTP bodies, it rejects it. Adding this value causes ISA to forward the “Accept-encoding” header and when the content is delivered compressed, ISA simply sends it back to the client as-is without inspecting it." HTH, Tom Thomas W Shinder, M.D., MCSESr. Consultant / Technical WriterProwess Consulting www.prowessconsulting.com PROWESS CONSULTING documentation | integration | virtuali