We are currently using CNR 22.214.171.124(redundant setup) and some of our clients are getting IP addresses and all the DNS information. The only thing is that they cannot connect to the internet through a web browser or anything that requires a DNS feature. Most can connect to IM stuff, but IE and Firefox won't connect. We have figured out that if we Disable the IP address they have and let the user get a new IP address, they can connect. We've seen this issue 3 or 4 times in the last 2 days, from the same VLAN.
Any ideas? If you need more info, let me know.