Jingjok Posted February 3, 2008 Share Posted February 3, 2008 Over the last year or two I’ve noticed some inexplicable effects when updating the website for a UK company. I’ll explain by way of an exercise I tried: 1. Establish a phone conversation with a UK colleague. 2. She and I view the UK server-hosted website in a browser window. 3. From Thailand, I upload an update using a web authoring and publishing application. To keep it simple, by changing one word of text. 4. I receive confirmation that this has occurred, but neither she nor I can see the change after refreshing our browsers. 5. Then she (from UK) uploads another update. 6. We both refresh our browsers. 7. This where is gets curiouser and curiouser: She (UK) can see the change, I (Thailand) cannot. ** Therefore I am looking at a webpage which should no longer exist.** 8. Bending the rules a little and looking at the page, from Thailand, routing via a friend's psyphon server in UK, I see the UK ('genuine') version. 9. Even weirder, the change I published earlier from Thailand will eventually appear, but not for a few hours, usually overnight. Can anyone, more knowledgeable of these matters than I, explain what is going on here? Presumably the site must be mirrored or intercepted in some way. Is this a Thai security issue, or normal internet practice? Link to comment Share on other sites More sharing options...
Kyosuken Posted February 3, 2008 Share Posted February 3, 2008 ISP using transparent proxy, or your company is using a proxy, or you have your browser configured with the ISP proxy CAT has a transparent proxy (ToT too if i recall). One way is to try to force a refresh with the browser (shift + F5), it works better in Firefox than IE though Another way is to reload the page and appending a fake query : http://www.somesite.com/index.html?fakequery=blablah (in other words append ?xxx=yyy to the url) Link to comment Share on other sites More sharing options...
nikster Posted February 4, 2008 Share Posted February 4, 2008 AFAIK all ISPs have proxy servers that cache content. I just didn't think it would work like this, guess I expected the cache to be a little smarter. Fake query at the end like Kyosuken said is your best bet. Or you get a VPN solution, cheap and easy to get. You then have a VPN to somewhere outside Thailand, and that accesses your web page, which should get you clean around the proxy. Link to comment Share on other sites More sharing options...
monty Posted February 4, 2008 Share Posted February 4, 2008 It's a bit weird in the uploading part! Never heard of uplinks being cached and sent on later. Actually this is plain impossible, since your webhost would not be able to send you the update confirmation, unless it has actually received that update! So I guess there is a delay at your webhost as well, they might have a proxy somewhere on their internet backbone as well! In the download link it's just proxy servers. All ISP's here have them, trying to keep the international pipe's load a bit lower. Very efficient for static pages, can only be a bit annoying after doing updates. However, even here in Thailand, the proxies are smart enough to understand the ctrl+F5 command, which will make them update the content at their proxy from the originating web host, so you get served the latest version. It's possible to code your website forcing any proxy between your host and somebody watching to only serve content directly from your host, and basically bypass the cache of the proxies. Link to comment Share on other sites More sharing options...
dsys Posted February 4, 2008 Share Posted February 4, 2008 (edited) Sounds normal(ish) to me. Looks like the proxy servers in Thailand are slower thatn the ones in the UK. I take it that the confirmation you recieve is from dreamweaver or your ftp program. can you ssh or rdp into the box and try a local view in a browser. Is the box running Linux? if so edit the .htaccess and add a proxy control section: Of course I could have completely missed the point here. heres an example I user on one of my sites (actually its a back up copy note dates of 2003). link [ http://httpd.apache.org/docs/2.2/mod/mod_expires.html [ #Cache control ExpiresActive On ExpiresByType image/x-icon A2592000 ExpiresByType application/x-javascript A604800 ExpiresByType text/css A604800 ExpiresByType image/gif A2592000 ExpiresByType image/png A604800 ExpiresByType image/jpeg A604800 ExpiresByType text/plain A604800 ExpiresByType application/x-shockwave-flash A604800 ExpiresByType video/x-flv A2592000 ExpiresByType application/pdf A604800 ExpiresByType text/html A-300 # YEAR <FilesMatch "\.(flv|gif|ico)$"> Header append Cache-Control "public, must-revalidate" </FilesMatch> # WEEK <FilesMatch "\.(pdf|swf|js|css|jpg|jpeg)$"> Header append Cache-Control "public, must-revalidate" </FilesMatch> # NEVER CACHE <FilesMatch "\.(html|cgi|php|htm)$"> Header unset Expires Header set Expires "Thu, 01 Dec 2003 16:00:00 GMT" Header unset Cache-Control Header set Cache-Control "no-store, no-cache, must-revalidate" Header set Pragma "no-cache" </FilesMatch> Edited February 4, 2008 by dsys Link to comment Share on other sites More sharing options...
Veazer Posted February 4, 2008 Share Posted February 4, 2008 You'll also need to be sure that your FTP or 'publishing' app is configured properly for the time difference between yourself and the server. If not, the browser may see files that are actually newer as being older because of the time difference. In FileZilla, the setting is in the advanced settings for each connection: Link to comment Share on other sites More sharing options...
dsys Posted February 4, 2008 Share Posted February 4, 2008 You'll also need to be sure that your FTP or 'publishing' app is configured properly for the time difference between yourself and the server. If not, the browser may see files that are actually newer as being older because of the time difference. In FileZilla, the setting is in the advanced settings for each connection: that is something that never crossed my mind before (like loads of other things) It raises an interesting question : What controls the file creation dates on a server? The server itself or the FTP program. Personally I had always thought it was the server, but can you specify the creation date when you create a file? - If so how do you do this? Link to comment Share on other sites More sharing options...
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