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Hi,

I have a packet capture taken on a proxy server.
The first packet is GET http://serveurl send from the client towards proxy. Then immediatly after that packet i get HTTP/1.1 404 not found. Then the client ACK's this HTTP not found packet.

Should the normal sequence not be:

CLIENT: HTTP GET
SERVER: TCP-ACK
SERVER: HTTP NOT FOUND
CLIENT TCP-ACK

It seems like i am missing an ACK packet. And maybe this is why i get an HTTP not found?

Or am i mistaken?

asked 25 Jun '14, 02:50

Herbaliser's gravatar image

Herbaliser
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accept rate: 0%

edited 25 Jun '14, 03:00

grahamb's gravatar image

grahamb ♦
19.8k330206

Does received HTTP/1.1 404 packet is part of same session.The 404 or Not Found error message is a HTTP standard response code indicating that the client was able to communicate with a given server, but the server could not find what was requested.Would be easier to answer if you share the capture.

(25 Jun '14, 02:58) kishan pandey

Hi,everything looks fine here,Generally, a Not Found status error (usually a 404 HTTP status code) is returned when we attempts to visit a page that doesn’t exist—either because you deleted or renamed it without redirecting the old URL to a new page, or because of a typo mistake in a link.

(25 Jun '14, 05:00) kishan pandey

No, you're not missing an ACK. In TCP, it is not necessary to have an ACK for every data packet. In this case, there is an ACK in the Not Found packet.

You're getting Not Found simply because the page was not found, not because of a missing ACK.

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answered 25 Jun '14, 05:05

Jim%20Aragon's gravatar image

Jim Aragon
7.2k733118
accept rate: 24%

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question asked: 25 Jun '14, 02:50

question was seen: 5,096 times

last updated: 25 Jun '14, 05:05

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