Proxy error (21)
serene56: I've been having trouble staying on this site and others over the past few nights as I'm getting this message:
Proxy Error
The proxy server received an invalid response from an upstream server.
The proxy server could not handle the request POST
Reason: DNS lookup failure for:
Apache Server at Port 3128Can anyone help please, can't stay on a page long enough to google
you get used to it after awhile , my quote button works when it wants to , posts go poof, gone as I get a run of things then it settles, yours may to .Proxy Error
The proxy server received an invalid response from an upstream server.
The proxy server could not handle the request POST
Reason: DNS lookup failure for:
Apache Server at Port 3128Can anyone help please, can't stay on a page long enough to google
Answeractiveoldestvotes
up vote
2
down vote
This is not mentioned in you post but I suspect you are initiating an SSL connection from the browser to Apache, where VirtualHosts are configured, and Apache does a revese proxy to your Tomcat.
There is a serious bug in (some versions ?) of IE that sends the 'wrong' host information in an SSL connection (see EDIT below) and confuses the Apache VirtualHosts. In short the server name presented is the one of the reverse DNS resolution of the IP, not the one in the URL.
The workaround is to have one IP address per SSL virtual hosts/server name. Is short, you must end up with something like
1 server name == 1 IP address == 1 certificate == 1 Apache Virtual Host
EDIT
Though the conclusion is correct, the identification of the problem is better described here
up vote
2
down vote
This is not mentioned in you post but I suspect you are initiating an SSL connection from the browser to Apache, where VirtualHosts are configured, and Apache does a revese proxy to your Tomcat.
There is a serious bug in (some versions ?) of IE that sends the 'wrong' host information in an SSL connection (see EDIT below) and confuses the Apache VirtualHosts. In short the server name presented is the one of the reverse DNS resolution of the IP, not the one in the URL.
The workaround is to have one IP address per SSL virtual hosts/server name. Is short, you must end up with something like
1 server name == 1 IP address == 1 certificate == 1 Apache Virtual Host
EDIT
Though the conclusion is correct, the identification of the problem is better described here
Introduction
A server (not necessarily a Web server) is acting as a gateway or proxy to fulfil the request by the client (e.g. your Web browser or our CheckUpDown robot) to access the requested URL. This server received an invalid response from an upstream server it accessed to fulfil the request.
This usually does not mean that the upstream server is down (no response to the gateway/proxy), but rather that the upstream server and the gateway/proxy do not agree on the protocol for exchanging data. Given that Internet protocols are quite clear, it often means that one or both machines have been incorrectly or incompletely programmed.
502 errors in the HTTP cycle
Any client (e.g. your Web browser or our CheckUpDown robot) goes through the following cycle when it communicates with the Web server:
Obtain an IP address from the IP name of the site (the site URL without the leading 'http://'). This lookup (conversion of IP name to IP address) is provided by domain name servers (DNSs).
Open an IP socket connection to that IP address.
Write an HTTP data stream through that socket.
Receive an HTTP data stream back from the Web server in response. This data stream contains status codes whose values are determined by the HTTP protocol. Parse this data stream for status codes and other useful information.
This error occurs in the final step above when the client receives an HTTP status code that it recognises as '502'. (Last updated: March 2012).
Fixing 502 errors - general
This problem is due to poor IP communication between back-end computers, possibly including the Web server at the site you are trying to visit. Before analysing this problem, you should clear your browser cache completely.
If you are surfing the Web and see this problem for all Web sites you try to visit, then either 1) your ISP has a major equipment failure/overload or 2) there is something wrong with your internal Internet connection e.g. your firewall is not functioning correctly. In the first case, only your ISP can help you. In the second case, you need to fix whatever it is that is preventing you reaching the Internet.
If you get this problem for only some of the Web sites you try to visit then it is likely to be a problem at those sites i.e. one of their pieces of equipment is failing/overloaded. Contact the people at those sites.
Fixing 502 errors - CheckUpDown
Use of proxies and caching is increasing on the Web. Our CheckUpDown robot will always try to 'drill through' to the real computer that actually hosts the Web site, but we do not have complete control over where our HTTP request actually ends up. If only one link in the chain of computers dealing with our HTTP request is broken, then an error such as 502 can easily occur.
Please contact us (email preferred) whenever you encounter 502 errors - there is nothing you can do to sort them out. We then have to liaise with your ISP and the vendor of the Web server software so that they can review the flow of IP data traffic between various computers under their control.
A server (not necessarily a Web server) is acting as a gateway or proxy to fulfil the request by the client (e.g. your Web browser or our CheckUpDown robot) to access the requested URL. This server received an invalid response from an upstream server it accessed to fulfil the request.
This usually does not mean that the upstream server is down (no response to the gateway/proxy), but rather that the upstream server and the gateway/proxy do not agree on the protocol for exchanging data. Given that Internet protocols are quite clear, it often means that one or both machines have been incorrectly or incompletely programmed.
502 errors in the HTTP cycle
Any client (e.g. your Web browser or our CheckUpDown robot) goes through the following cycle when it communicates with the Web server:
Obtain an IP address from the IP name of the site (the site URL without the leading 'http://'). This lookup (conversion of IP name to IP address) is provided by domain name servers (DNSs).
Open an IP socket connection to that IP address.
Write an HTTP data stream through that socket.
Receive an HTTP data stream back from the Web server in response. This data stream contains status codes whose values are determined by the HTTP protocol. Parse this data stream for status codes and other useful information.
This error occurs in the final step above when the client receives an HTTP status code that it recognises as '502'. (Last updated: March 2012).
Fixing 502 errors - general
This problem is due to poor IP communication between back-end computers, possibly including the Web server at the site you are trying to visit. Before analysing this problem, you should clear your browser cache completely.
If you are surfing the Web and see this problem for all Web sites you try to visit, then either 1) your ISP has a major equipment failure/overload or 2) there is something wrong with your internal Internet connection e.g. your firewall is not functioning correctly. In the first case, only your ISP can help you. In the second case, you need to fix whatever it is that is preventing you reaching the Internet.
If you get this problem for only some of the Web sites you try to visit then it is likely to be a problem at those sites i.e. one of their pieces of equipment is failing/overloaded. Contact the people at those sites.
Fixing 502 errors - CheckUpDown
Use of proxies and caching is increasing on the Web. Our CheckUpDown robot will always try to 'drill through' to the real computer that actually hosts the Web site, but we do not have complete control over where our HTTP request actually ends up. If only one link in the chain of computers dealing with our HTTP request is broken, then an error such as 502 can easily occur.
Please contact us (email preferred) whenever you encounter 502 errors - there is nothing you can do to sort them out. We then have to liaise with your ISP and the vendor of the Web server software so that they can review the flow of IP data traffic between various computers under their control.
Thanks guys, I did get to read some info similar to what Rob put up, but it was confusing because I haven't actually done/changed anything 
Is there anything I can do, or do you think the situation will resolve itself (see, it's alright now lol)
Is there anything I can do, or do you think the situation will resolve itself (see, it's alright now lol)
serene56: Thanks guys, I did get to read some info similar to what Rob put up, but it was confusing because I haven't actually done/changed anything Is there anything I can do, or do you think the situation will resolve itself (see, it's alright now lol)
Oh, thanks Rob, I just read your last post. Have cleared my browsing history, will see how that goes
wouldn't hurt to run Ccleaner
if you haven't got that can download free copy here
if you haven't got that can download free copy here
robplum: wouldn't hurt to run Ccleaner
if you haven't got that can download free copy here
if you haven't got that can download free copy here
Thanks Rob, I'll give it a shot when my connection is more stable
Seems to have improved since I cleared my browser cache, fingers crossed..
yeah, Ccleaner does really good job, in left menu i suggest deselect index dat and passwords clean, leave advanced unchecked
then Run then on finish click fix now
Can get it to back up the trash if you want
(I don't bother)
Also Crap-cleaner has Registry Clean Function i use it often others say don't however i do
then Run then on finish click fix now
Can get it to back up the trash if you want
(I don't bother)
Also Crap-cleaner has Registry Clean Function i use it often others say don't however i do
robplum: yeah, Ccleaner does really good job, in left menu i suggest deselect index dat and passwords clean, leave advanced unchecked
then Run then on finish click fix now
Can get it to back up the trash if you want
(I don't bother)
Also Crap-cleaner has Registry Clean Function i use it often others say don't however i do
then Run then on finish click fix now
Can get it to back up the trash if you want
(I don't bother)
Also Crap-cleaner has Registry Clean Function i use it often others say don't however i do
So it won't clash with my current security thingy I'm using
serene56: So it won't clash with my current security thingy I'm using
no it won't its function is to clean out the crap
Cleans junk Windows never cleans. Windows only removes short cut link to deleted stuff and almost never removes heaps temp files windows creates
as well ccleaner cleans your browser files, as other function like handle start up files, reg cleaner, drive wiper (over-wipes the empty space on your hard drive) not files.
Ccleaner is widely used and trusted, no it won't effect your anti-virus.
thats the problem i had when i used avg free trial anti virus and my comp was also slow by neraly 50%,i changed to trend micro titanium,and they wiped out my problem somehow and my comp got fastereven with their free trial which only took 10mins to downlad
rippleinapond: thats the problem i had when i used avg free trial anti virus and my comp was also slow by neraly 50%,i changed to trend micro titanium,and they wiped out my problem somehow and my comp got fastereven with their free trial which only took 10mins to downlad
today old mate told where an old mine is located that few would know about has big MULLOCK HEAP
sounds like you might have had some problem with the avg install or malware in your computer
i know lot people using free avg, I DON'T, whatever you use it must be monitoring all the computers open ports when your connected to the internet
robplum: today old mate told where an old mine is located that few would know about has big MULLOCK HEAP
sounds like you might have had some problem with the avg install or malware in your computer
i know lot people using free avg, I DON'T, whatever you use it must be monitoring all the computers open ports when your connected to the internet
whatever it is its working better than it ever did haha, i know nothing about computerslol,but bought this lappie on facebook buy swapand sell,for 100bucks,and its working great,an old panasonic .Gee try those mullock heaps with yr dtector,i went over the same one about ten times ,nothing,then a yr later ,a 20gram nugg and a chinese coin,reckon the rain washes away pieces that block the signal...maybesounds like you might have had some problem with the avg install or malware in your computer
i know lot people using free avg, I DON'T, whatever you use it must be monitoring all the computers open ports when your connected to the internet
yeah i'm going to take the detector there
I running this new one now, might sort my old one some time it still goes but think maybe the drive is doggy so might replace it, tis better built than this one
I running this new one now, might sort my old one some time it still goes but think maybe the drive is doggy so might replace it, tis better built than this one
robplum: yeah i'm going to take the detector there
I running this new one now, might sort my old one some time it still goes but think maybe the drive is doggy so might replace it, tis better built than this one
got this tough book which are worth about 5000bucks new in think,and the guy rebuilt it in trade school,and it works fine so far ,but for a hundred bucks lol if nit carks it, i,ll just ditch it hahaI running this new one now, might sort my old one some time it still goes but think maybe the drive is doggy so might replace it, tis better built than this one
oh they are pretty good, telstra use them i thnk
robplum: oh they are pretty good, telstra use them i thnk
always liked them yes i saw a telstra guy using one as he had to show where he was working to the head office,when nhe came to my place.they are tough ,but i think this one has different guts,as it was pulled apart,but it,ll do nme for now nlol.dont know how long ill be on here ,i think i,ll get banned for a comment i made in the interson the say anythung thread lol,but never know haha
Grrrrrrrrrrrrrr Rob and co you have done it again
Anyway if I ever had a prob I just go to system restore as my desktop is (hopefully) like fort knox with AVG pro, CCleaner, Super Anti Spyware and Malwarebytes Anti Malaware.
So I know its my error and can reverse it.
Anyway if I ever had a prob I just go to system restore as my desktop is (hopefully) like fort knox with AVG pro, CCleaner, Super Anti Spyware and Malwarebytes Anti Malaware.
So I know its my error and can reverse it.
serene56: I've been having trouble staying on this site and others over the past few nights as I'm getting this message:
Proxy Error
The proxy server received an invalid response from an upstream server.
The proxy server could not handle the request POST
Reason: DNS lookup failure for:
Apache Server at Port 3128Can anyone help please, can't stay on a page long enough to google
Proxy Error
The proxy server received an invalid response from an upstream server.
The proxy server could not handle the request POST
Reason: DNS lookup failure for:
Apache Server at Port 3128Can anyone help please, can't stay on a page long enough to google
That's it. Blame the Indians and not the cowboys who designed the site.
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Created: Sep 2012
Last Viewed: Apr 7
Last Commented: Sep 2012
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Proxy Error
The proxy server received an invalid response from an upstream server.
The proxy server could not handle the request POST
Reason: DNS lookup failure for:
Apache Server at
Can anyone help please, can't stay on a page long enough to google