If "always_direct" is used for systems in a specific domain, will a Squid proxy query its peers for cached content? (1) WPAD is defined in the local DNS zone to support the automatic detection of web proxies. Assuming that automatic detection is enabled, Linux- and older Windows- based will locate and use the proxy.pac/wpad.dat configuration file; however, WindowsXP-based systems will not. (2) DHCP is configured to pass Option 252 to pass the URL for the web proxy automatic configuration script. Assuming that automatic detection is enabled, WindowsXP-based systems will only use the proxy.pac/wpad.dat file when configured for DHCP and Option 252 is defined to the URL. (3) The same proxy.pac/wpad.dat file that defines a simple hashing algorithm to balance the load between two Squid proxy servers. When a Mozilla-based browser (FireFox, Mozilla, Netscape, etc.) is used, load-balancing works as expected. When Internet Explorer is used, the load-balancing fails. If a specific web server has never been accessed, the hashing alforithm is used to select the web proxy. However, once a proxy selection has been made, Internet Explorer will use that proxy for all accesses to that specific web server. The load-balanced proxy servers have a common parent that sits on the network security perimeter to provide access to Internet content. When content is being retrieved from the Internet it doesn't matter whether one Windows system selected proxy A and another selected proxy B. If the content is cacheable, it will be retrieved from the parent's cache. The parent proxy can access both external Internet content and internal corporate content over our wide area network. At present, "always_direct" is only used on the load-balanced proxy serversto access web servers in our local facility. I would like to use "always_direct" on the proxies for all internal corporate web content. If all browsers used the hashing algorithm for all requests, there would be no question about using "always_direct" as the browser would select the proxy that would have the content cached. The question is does the proxy query its peers before applying the "always_direct" rule? If not, does this behaviour change when using NetDB? Merton Campbell Crockett -- BEGIN: vcard VERSION: 3.0 FN: Merton Campbell Crockett ORG: General Dynamics Advanced Information Systems; Intelligence and Exploitation Systems N: Crockett;Merton;Campbell EMAIL;TYPE=internet: mcc@xxxxxxxxxxxxxxx TEL;TYPE=work,voice,msg,pref: +1(805)497-5045 TEL;TYPE=work,fax: +1(805)497-5050 TEL;TYPE=cell,voice,msg: +1(805)377-6762 END: vcard
