Re: TCP DNS requests

["Douglas K. Fischer" <fischerdk () purefm net>]

At 08:46 AM 10/30/2002, Carl R Diliberto wrote:
> We are reporting TCP based DNS requests to one of our DNS servers coming
> from internal, client IP addresses.  My manager would like to block the TCP
> packets.  What or why would their be random TCP packets?  We monitored
> several clients and it appears it only needs UDP.

DNS will use TCP if the response is > 512 bytes. It is perfectly valid for 
an internal client system to receive a TCP DNS response in such a case.

Doug


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