> Is there any problem or disadvantage of creating > CNAME in the DNS to point to an outside domain or
The only real downside to a CNAME record is that it can cause an additional DNS lookup for the client's DNS resolver. If the CNAME is to a name within the same domain (i.e. m.example.com -> www.example.com), the responding DNS server will usually include additional answers in anticipation of the extra lookup, so it would return the CNAME reference and go ahead and include the IP for www.example.com as well. If the CNAME is linked to a domain the server isn't authoritative for then the response will usually just include the reference and no additional answers, so if m.example.com -> www.other-example.com then it would just return the reference and the resolver will need to go initiate another lookup for www.other-example.com on its own which adds some time to the resolution process. This is the same reason that the DNS server delegations should be on the same TLD as the domain itself whenever possible, to avoid additional lookups. If the TTL settings are reasonable then it can add a few ms of time to the initial lookup, but the responses are cached after that so additional requests should be fast either way. As long as all of the DNS servers involved respond quickly and there isn't a lot of network latency then it will be pretty much invisible to your visitors even with the added lookup time. -Justin Scott ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Order the Adobe Coldfusion Anthology now! http://www.amazon.com/Adobe-Coldfusion-Anthology-Michael-Dinowitz/dp/1430272155/?tag=houseoffusion Archive: http://www.houseoffusion.com/groups/cf-talk/message.cfm/messageid:335756 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/groups/cf-talk/unsubscribe.cfm
