I am experiencing an issue where my Cisco 877 router's ATM interface keeps restarting due to dhcp lease timeout from my ISP every hour. I resolved this issue by applying an inbound ACL permitting DHCP packets on the ATM interface.
But... The only way I could get this ACL to work was by removing the static 1 to 1 NAT rule forwarding all incoming traffic. to my internal firewall.
It seems that I cannot both have an ACL inbound on the ATM and a static 1 to 1 NAT statement to work in conjunction with one another.
If my ISP would allow me to configure my static ip manually on the ATM then I wouldn't have this issue but they will not allow me to do this.
Is this how IOS works? I am running 12.4(24) T8 advanced ip services using a Cisco 877-M router.
What happens is the lease from the ISP is 3400seconds, 1hr. The router tries to rebind the address every 30 mins. But the router never receives the dhcp reply from ISP so dhcp lease expires and restarts ATM interface.
As soon as I apply a permit ip any any ACL to ATM interface, router receives reply packets from dhcp and ATM never drops.
Then I add a static NAT rule, and this breaks dhcp replies again despite the permit ip any any ACL.
We are pleased to announce availability of Beta software for 16.6.3. 16.6.3 will be the second rebuild on the 16.6 release train targeted towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are looking for early feedback from custome...