I recently configured a cisco ASA 5500 firewall with PAT & basic filters. Everything is ok other than DNS. I dont have any internal DNS servers I am using my ISPs DNS servers for name resolutions. In the nslookup utility of a client computer all the URLs are getting resolves perfectly. But I type the same URL in the browser it's not working. But if I type the IP address of the same URL in the browser it works perfectly. Wonder why this happen. Is this something to do with maximum DNS packet size or something else. Please let me know.
Thanks in advance
Here I am attaching the sh run output and the syslog messages
Table of ContentsIntroductionVersion HistoryPossible Future
UpdatesDocuments PurposeNAT Operation in ASA 8.3+ SectionsRule Types
Network Object NATTwice NAT / Manual NATRule Types used per SectionNAT
Types used with Twice NAT / Manual NAT and Network Obje...
Table of Contents Introduction:This document describes details on how
NAT-T works. Background: ESP encrypts all critical information,
encapsulating the entire inner TCP/UDP datagram within an ESP header.
ESP is an IP protocol in the same sense that TCP an...