Browser not honoring DNS Anyone faced issues with stuck clients while using GTM

Hi all browsers perform some sort of DNS caching as far as I know, some only for a few seconds. By default most versions of IE cache for 30mins. This can be changed by a registry setting so if someone is seeing no DNS caching for multiple versions of IE I would suggest that your companys SOE may have been modified. The way they behave changes from version to version.

GTM is not a standalone technology to address geo-redundancy and site failover. You must implement other designs to complement GTM ie. BGP failover/ multi-site LTM pools, site-specific redirect. Whatever you do, do not rely on GTM persistence setting for internet users - it will work for approx. 70% of users only and you need another solution to address the remaining 30%. The reason is that you cannot guarantee that a users LDNS will remain constant for the duration of a browser session. Even if your ISP does it right, the next one along won't.

Anyone who uses GTM should read this http://www.tenereillo.com/GSLBPageOfShame.htm to understand - don't be fooled by the name it's great GSLB primer - GTM technology is valid but it's limitations need to be understood by those design solutions around it.