[squid-users] Expect Request headers
Hello I have some software that is producing repeated TCP_MISS/417 errors in the logs and is failing to connect to the server I have found previous discussions that show the software is not behaving correctly to the extent that after the proxy sends back the 417 - expectation failed, the client should send the request without the header. This is not happening. A sniff of the traffic shows that after the 417 is sent back the client simply repeats the request unchanged. This repeats. All of this is using squid 2.7STABLE3 on debian 5 (lenny). As an aside, nothing on these proxies has changed so I am at a loss in that respect. These proxies have a cache-peer configured. When I point the client software directly at these cache-peer hosts (which I do not control) the connection works. These proxies are squid 2.6STABLE22. With these upstream ones there may be other differences (such as OS etc) but I have no visibility to them to check). (obfuscated) Extract of sniff while connecting as best I can do it is as follows. The fail to connect via my proxy (squid 2.7STABLE3): Client request: Hypertext Transfer Protocol POST http://www.somehost.com/api/SomeService.svc HTTP/1.1\r\n Request Method: POST Request URI: http://www.somehost.com/api/SomeService.svc Request Version: HTTP/1.1 Content-Type: text/xml; charset=utf-8\r\n SOAPAction: http://tempuri.org/SomeService/GetServerSettings\r\n Host: www.somehost.com\r\n Content-Length: 233 Expect: 100-continue\r\n Proxy-Connection: Keep-Alive\r\n Proxy response: Hypertext Transfer Protocol HTTP/1.0 417 Expectation failed\r\n Request Version: HTTP/1.0 Response Code: 417 Server: squid/2.7.STABLE3\r\n Date: Thu, 20 Jan 2011 13:27:49 GMT\r\n Content-Type: text/html\r\n Content-Length: 1476 Expires: Thu, 20 Jan 2011 13:27:49 GMT\r\n X-Squid-Error: ERR_INVALID_REQ 0\r\n X-Cache: MISS from my.squid.proxy\r\n X-Cache-Lookup: NONE from my.squid.proxy:8080\r\n Via: 1.0 my.squid.proxy:8080 (squid/2.7.STABLE3)\r\n Connection: close\r\n \r\n And this simply repeats - the client sends the same request again. Using the upstream proxy (squid 2.6 STABLE22) - it works Client request: Hypertext Transfer Protocol POST http://www.somehost.com/api/SomeService.svc HTTP/1.1\r\n [Expert Info (Chat/Sequence): POST http://www.somehost.com/api/SomeService.svc HTTP/1.1\r\n] [Message: POST http://www.somehost.com/api/SomeService.svc HTTP/1.1\r\n] [Severity level: Chat] [Group: Sequence] Request Method: POST Request URI: http://www.somehost.com/api/SomeService.svc Request Version: HTTP/1.1 Content-Type: text/xml; charset=utf-8\r\n SOAPAction: http://tempuri.org/SomeService/GetServerSettings\r\n Host: www.somehost.com\r\n Content-Length: 233\r\n [Content length: 233] Expect: 100-continue\r\n Proxy-Connection: Keep-Alive\r\n \r\n UpstreamProxy reply: Hypertext Transfer Protocol HTTP/1.0 200 OK\r\n [Expert Info (Chat/Sequence): HTTP/1.0 200 OK\r\n] [Message: HTTP/1.0 200 OK\r\n] [Severity level: Chat] [Group: Sequence] Request Version: HTTP/1.0 Response Code: 200 Date: Thu, 20 Jan 2011 06:17:58 GMT\r\n Server: Microsoft-IIS/6.0\r\n X-Powered-By: ASP.NET\r\n X-AspNet-Version: 2.0.50727\r\n Cache-Control: private\r\n Content-Type: text/xml; charset=utf-8\r\n Content-Length: 823\r\n [Content length: 823] X-Cache: MISS from another.upstream.proxy\r\n X-Cache-Lookup: MISS from another.upstream.proxy:8079\r\n X-Cache: MISS from the.cache.peer.proxy\r\n X-Cache-Lookup: MISS from the.cache.peer.proxy:8080\r\n Via: 1.0 another.upstream.proxy:8079 (squid/2.6.STABLE20), 1.0 the.cache.peer.proxy:8080 (squid/2.6.STABLE22)\r\n Proxy-Connection: keep-alive\r\n \r\n Any suggestions on why the difference but more importantly how to fix would be enormously appreciated. Many thanks rolf.
Re: [squid-users] Expect Request headers
On 21/01/11 02:48, Rolf Loudon wrote: Hello I have some software that is producing repeated TCP_MISS/417 errors in the logs and is failing to connect to the server I have found previous discussions that show the software is not behaving correctly to the extent that after the proxy sends back the 417 - expectation failed, the client should send the request without the header. This is not happening. A sniff of the traffic shows that after the 417 is sent back the client simply repeats the request unchanged. This repeats. All of this is using squid 2.7STABLE3 on debian 5 (lenny). As an aside, nothing on these proxies has changed so I am at a loss in that respect. These proxies have a cache-peer configured. When I point the client software directly at these cache-peer hosts (which I do not control) the connection works. These proxies are squid 2.6STABLE22. With these upstream ones there may be other differences (such as OS etc) but I have no visibility to them to check). (obfuscated) Extract of sniff while connecting as best I can do it is as follows. The fail to connect via my proxy (squid 2.7STABLE3): This is what is happening... Client request: Hypertext Transfer Protocol POST http://www.somehost.com/api/SomeService.svc HTTP/1.1\r\n Request Method: POST Request URI: http://www.somehost.com/api/SomeService.svc Request Version: HTTP/1.1 Content-Type: text/xml; charset=utf-8\r\n SOAPAction: http://tempuri.org/SomeService/GetServerSettings\r\n Host: www.somehost.com\r\n Content-Length: 233 Expect: 100-continue\r\n Proxy-Connection: Keep-Alive\r\n Notice how there is zero bytes of body here. Despite the headers saying 233 would follow. What this client is *Expecting* back is a 100 continue response indicating Send me the body. This is one of the more advanced HTTP/1.1 efficiency features. Squid-2 is of course HTTP/1.0 software and can't do that reply correctly. Cannot even transmit them properly. 2.6 sends HTTP/1.0 to the server which all seem smart enough to identify the problems and not screw the transaction by sending 100 replies back. 2.7 is *just* smart enough with its HTTP/1.1 support to tell the client about this problem via the 417 and swallow silently any 100 messages received. Proxy response: Hypertext Transfer Protocol HTTP/1.0 417 Expectation failed\r\n Request Version: HTTP/1.0 Response Code: 417 Server: squid/2.7.STABLE3\r\n Date: Thu, 20 Jan 2011 13:27:49 GMT\r\n Content-Type: text/html\r\n Content-Length: 1476 Expires: Thu, 20 Jan 2011 13:27:49 GMT\r\n X-Squid-Error: ERR_INVALID_REQ 0\r\n X-Cache: MISS from my.squid.proxy\r\n X-Cache-Lookup: NONE from my.squid.proxy:8080\r\n Via: 1.0 my.squid.proxy:8080 (squid/2.7.STABLE3)\r\n Connection: close\r\n \r\n And this simply repeats - the client sends the same request again. Client software that follows a 417 message with an repeat using Expect: header is broken. Please mention this to the relevant people. Point them at RFC 2616. Using the upstream proxy (squid 2.6 STABLE22) - it works snip Any suggestions on why the difference but more importantly how to fix would be enormously appreciated. Many thanks 2.7 has more HTTP/1.1 support. To the point of advertising to the server that it can receive HTTP/1.1 replies. In Squid-2.7 you can suppress the 417 message generation and cause one of the following to happen by setting ignore_expect_100 on in squid.conf. (1) server responds earlier than it should, causing the transfer to be truncated mid-transfer if the POST was long. Corrupted data etc. (2) Squid and Server both waits for the mentioned 233 bytes of body. and waits, and waits. (2a) Eventually the client times out and sends the body, allowing the server to create the right response. (2b) Eventually the client times out and displays an error page. These *will* cause slower transfers for *all* clients attempting this feature, not just the broken ones. HTTP/1.1 *requires* all software sending Expect: to retry without the Expect: header on receiving a 417 response. For the record: 2.6 and 3.0 are paired in their non-support. 2.7 and 3.1 are paired in their partial support with the same override directive. 3.2 supports the expect-100 feature and has no known problems with this. Amos -- Please be using Current Stable Squid 2.7.STABLE9 or 3.1.10 Beta testers wanted for 3.2.0.4
[squid-users] Expect Request headers
Hello I have some software that is producing repeated TCP_MISS/417 errors in the logs and is failing to connect to the server I have found previous discussions that show the software is not behaving correctly to the extent that after the proxy sends back the 417 - expectation failed, the client should send the request without the header. This is not happening. A sniff of the traffic shows that after the 417 is sent back the client simply repeats the request unchanged. This repeats. All of this is using squid 2.7STABLE3 on debian 5 (lenny). As an aside, nothing on these proxies has changed so I am at a loss in that respect. These proxies have a cache-peer configured. When I point the client software directly at these cache-peer hosts (which I do not control) the connection works. These proxies are squid 2.6STABLE22. With these upstream ones there may be other differences (such as OS etc) but I have no visibility to them to check). (obfuscated) Extract of sniff while connecting as best I can do it is as follows. The fail to connect via my proxy (squid 2.7STABLE3): Client request: Hypertext Transfer Protocol POST http://www.somehost.com/api/SomeService.svc HTTP/1.1\r\n Request Method: POST Request URI: http://www.somehost.com/api/SomeService.svc Request Version: HTTP/1.1 Content-Type: text/xml; charset=utf-8\r\n SOAPAction: http://tempuri.org/SomeService/GetServerSettings\r\n Host: www.somehost.com\r\n Content-Length: 233 Expect: 100-continue\r\n Proxy-Connection: Keep-Alive\r\n Proxy response: Hypertext Transfer Protocol HTTP/1.0 417 Expectation failed\r\n Request Version: HTTP/1.0 Response Code: 417 Server: squid/2.7.STABLE3\r\n Date: Thu, 20 Jan 2011 13:27:49 GMT\r\n Content-Type: text/html\r\n Content-Length: 1476 Expires: Thu, 20 Jan 2011 13:27:49 GMT\r\n X-Squid-Error: ERR_INVALID_REQ 0\r\n X-Cache: MISS from my.squid.proxy\r\n X-Cache-Lookup: NONE from my.squid.proxy:8080\r\n Via: 1.0 my.squid.proxy:8080 (squid/2.7.STABLE3)\r\n Connection: close\r\n \r\n And this simply repeats - the client sends the same request again. Using the upstream proxy (squid 2.6 STABLE22) - it works Client request: Hypertext Transfer Protocol POST http://www.somehost.com/api/SomeService.svc HTTP/1.1\r\n [Expert Info (Chat/Sequence): POST http://www.somehost.com/api/SomeService.svc HTTP/1.1\r\n] [Message: POST http://www.somehost.com/api/SomeService.svc HTTP/1.1\r\n] [Severity level: Chat] [Group: Sequence] Request Method: POST Request URI: http://www.somehost.com/api/SomeService.svc Request Version: HTTP/1.1 Content-Type: text/xml; charset=utf-8\r\n SOAPAction: http://tempuri.org/SomeService/GetServerSettings\r\n Host: www.somehost.com\r\n Content-Length: 233\r\n [Content length: 233] Expect: 100-continue\r\n Proxy-Connection: Keep-Alive\r\n \r\n UpstreamProxy reply: Hypertext Transfer Protocol HTTP/1.0 200 OK\r\n [Expert Info (Chat/Sequence): HTTP/1.0 200 OK\r\n] [Message: HTTP/1.0 200 OK\r\n] [Severity level: Chat] [Group: Sequence] Request Version: HTTP/1.0 Response Code: 200 Date: Thu, 20 Jan 2011 06:17:58 GMT\r\n Server: Microsoft-IIS/6.0\r\n X-Powered-By: ASP.NET\r\n X-AspNet-Version: 2.0.50727\r\n Cache-Control: private\r\n Content-Type: text/xml; charset=utf-8\r\n Content-Length: 823\r\n [Content length: 823] X-Cache: MISS from another.upstream.proxy\r\n X-Cache-Lookup: MISS from another.upstream.proxy:8079\r\n X-Cache: MISS from the.cache.peer.proxy\r\n X-Cache-Lookup: MISS from the.cache.peer.proxy:8080\r\n Via: 1.0 another.upstream.proxy:8079 (squid/2.6.STABLE20), 1.0 the.cache.peer.proxy:8080 (squid/2.6.STABLE22)\r\n Proxy-Connection: keep-alive\r\n \r\n Any suggestions on why the difference but more importantly how to fix would be enormously appreciated. Many thanks rolf.
Re: [squid-users] Expect Request headers
see previous answers.
