Dave, CNAME records make it possible to introduce recursion errors. The extra lookup is definitely an issue for small data centers trying to maximize bandwidth and resources. And from a management standpoint it seems easier to work with 1 less kind of record.
-Mark -----Original Message----- From: Dave Watts [mailto:[EMAIL PROTECTED] Sent: Friday, November 18, 2005 1:46 PM To: CF-Talk Subject: RE: Multiple sites in IIS - Modifying DNS > You CAN alias records within the same zone, but it's > generally not a good idea because of the extra DNS > lookups required to resolve them. Just because you > can do a think, does not mean you should. Again, though, this is what CNAME records are for. The extra DNS lookups do not cause a significant amount of traffic, in my experience, even with DNS servers that support high-volume sites. I suspect this may have been more of an issue in the past than it is now, or maybe for DNS servers that support even higher numbers of queries it is still true. However, using multiple A records for a single IP address can introduce other problems, and I prefer the set of problems you may get by using CNAME records to the set of problems that you may get by using A records for aliasing. For example, if you're using the Microsoft DNS server - which, being integral to AD and Windows Networking, many people are - you can easily screw up your PTR records, as each time you add an A record it will, by default, rewrite the PTR record to point to the new host name. Dave Watts, CTO, Fig Leaf Software http://www.figleaf.com/ Fig Leaf Software provides the highest caliber vendor-authorized instruction at our training centers in Washington DC, Atlanta, Chicago, Baltimore, Northern Virginia, or on-site at your location. Visit http://training.figleaf.com/ for more information! ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Find out how CFTicket can increase your company's customer support efficiency by 100% http://www.houseoffusion.com/banners/view.cfm?bannerid=49 Message: http://www.houseoffusion.com/lists.cfm/link=i:4:224702 Archives: http://www.houseoffusion.com/cf_lists/threads.cfm/4 Subscription: http://www.houseoffusion.com/lists.cfm/link=s:4 Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4 Donations & Support: http://www.houseoffusion.com/tiny.cfm/54