Re: redirection loop

Maybe I'm shooting in the wrong direction, but isn't a redirect loop just that? One website issues a redirect to another website, which in turn redirects back to the first website and you're stuck in an endless loop with no hope of reaching either website.

I once caused this on my own website using mod_rewrite to add a '/' to URLs. I mistakenly issued a re-direct with the modified URL instead of just passing through to serve up the page. Firefox got the redirect and carried on with the modified URL ending in '/'. IE got the redirect, stripped the trailing '/' and tried again, and again, and again. It was a very effective IE blocker.

But I guess my point is, I wouldn't be surprised if you came across a mis-configured (intentionally?) web server that's causing a redirect loop so this error must be expected. It may also be that LWP::UserAgent is modifying the URL in some way that keeps the redirect looping.

Comment on Re: redirection loop

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Re^2: redirection loop by mrguy123 (Hermit) on May 14, 2006 at 07:14 UTC
The thing is, I can do the redirection manually. I can find the url redirection link in the retrieved web page, and use it to retrieve the web page I want. This works, but it is very long and ugly, and I would rather use the LWP::UserAgent redirection if I can. Also, the page that I get back with the redirection loop is a page that can be redirected (it has the redirection url link), so I don't think that something is wrong with the website.	[reply]
Re^3: redirection loop by ruzam (Curate) on May 14, 2006 at 15:13 UTC
Do you have a page example? According to the docks the redirect limit in LWP::UserAgent is set to 7 unless you change it with the 'max_redirect' option. I can't think of a reason why you would need to set it beyond 7. If you've some how set it to 0 then that would explain a few things.	[reply]
Re^4: redirection loop by mrguy123 (Hermit) on May 15, 2006 at 14:16 UTC
Thanks for your reply. I don't think the redirect option is set to 0, because in most cases (80%) the LWP::UserAgent redirection works fine. This is what I get when I print the retrieved page header: Date: Mon, 15 May 2006 14:08:20 GMT Location: /libweb/australia/do/login Server: Apache Tomcat/4.1.12 (HTTP/1.1 Connector) Content-Length: 65 Content-Type: text/html; charset=UTF-8 Client-Date: Mon, 15 May 2006 14:05:43 GMT Client-Response-Num: 1 Client-Warning: Redirect loop detected The page itself is an error message. I don't think that there are more than 7 redirections, because when I can redirect it manually without too much trouble (although I don't want to use this solution). If you have any other ideas I would be happy to hear them. Thanks, Guy Naamati	[reply]
Re^5: redirection loop by ruzam (Curate) on May 16, 2006 at 17:09 UTC
Re^4: redirection loop by mrguy123 (Hermit) on May 17, 2006 at 08:47 UTC
Well, thanks for the help. If I ever figure it out I will let you know, although the javascript answer seems quite possible (javascript has been giving me trouble before). Thanks again Guy Naamati	[reply]