NAT timeout

Hi,

I have a problem with a Cisco 1841 router running IOS Version 12.3(11)T5.

I use NAT to access the Internet through the router.

Sometimes, around 3-4 times a day, all Internet access stops because our DNS
server cannot access the Internet to resolve addresses. All Internet
communication from this server is stoped. If I issue a "clear ip nat
translation *" command to the router i ..
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