At 12:08 PM 3/10/00 -0800, you wrote:
I was just wondering if there are any downfalls to having multiple PTR entries for the same IP. As of now I have a PTR for every domain that I am hosting on my machine. No problems yet.... just wondering. thanks.
You should only have one PTR record for each IP#. Here's what O'Reilly's book "DNS and Bind" says about it:
(Here's the situation: A nameserver has been set up with "wormhole.movie.edu" sharing the same IP# as "wh249.movie.edu"; now the quoted explanation:)
"Thus 192.249.249.1 maps to "wormhole" and not to "wh249". You can create two PTR records, one for "wormhole" and one for "wh249", but most systems are not prepared to see more than one name for an address."
It doesn't say what will happen, and as you've found out by experience; usually the effect is benign. However, since there is no defined behavior for what a nameserver is supposed to do if it finds multiple names for one IP#, anything could happen, including that the nameserver (or the program to which the nameserver feeds the returned data) will overload buffer space and crash. Best not to do it.
Jeff -- Jeff Lasman <jblists@xxxxxxxxxxxxx>