02-12-2006 10:14 AM - edited 03-03-2019 11:43 AM
I'm running a Cisco 1811 and getting my IP address from the CableModem (OOL).
The router is at 192.168.1.1 and also has its public IP from the CableModem.
From the Router I can ping myself via 192.168.1.1, but I can't ping myself if I use my public IP which is assigned via DHCP I believe.
This is my ACL for FE0 in (CableModem):
access-list 101 permit udp any eq bootps any eq bootpc
access-list 101 deny ip 10.0.0.0 0.255.255.255 any
access-list 101 deny ip 172.16.0.0 0.15.255.255 any
access-list 101 deny ip 192.168.0.0 0.0.255.255 any
access-list 101 deny ip 192.168.1.0 0.0.0.255 any
access-list 101 deny ip 127.0.0.0 0.255.255.255 any
access-list 101 deny ip host 255.255.255.255 any
access-list 101 permit icmp any any echo-reply
access-list 101 permit icmp any any time-exceeded
access-list 101 permit icmp any any unreachable
access-list 101 permit tcp host x.x.x.x any
access-list 101 permit udp host x.x.251.5 eq domain any
access-list 101 permit tcp host x.x.251.5 eq domain any
access-list 101 permit udp host x.x.x.69 eq domain any
access-list 101 permit tcp host x.x.x.69 eq domain any
access-list 101 permit tcp any any eq 22
access-list 101 deny ip any any
I can't find the reason via debugs or logs, nothing shows up.
When I ping my internet ip, then show the access-list(count), the last line (deny ip any any) increases by 5 (the pings). But I don't know why, I thought the ACL icmp lines above should allow that.
Why can't I ping from the router to myself (my internet ip) ?
What am I missing ?
Thanks !
Matthew
Solved! Go to Solution.
02-12-2006 11:30 AM
Hi Matthew,
Change your ACL so that it looks like this (you will have to remove it completely and re-add this):
access-list 101 permit udp any eq bootps any eq bootpc
access-list 101 deny ip 10.0.0.0 0.255.255.255 any
access-list 101 deny ip 172.16.0.0 0.15.255.255 any
access-list 101 deny ip 192.168.0.0 0.0.255.255 any
access-list 101 deny ip 192.168.1.0 0.0.0.255 any
access-list 101 deny ip 127.0.0.0 0.255.255.255 any
access-list 101 deny ip host 255.255.255.255 any
access-list 101 permit icmp any any echo !!!! NEW LINE
access-list 101 permit icmp any any echo-reply
access-list 101 permit icmp any any time-exceeded
access-list 101 permit icmp any any unreachable
access-list 101 permit tcp host x.x.x.x any
access-list 101 permit udp host x.x.251.5 eq domain any
access-list 101 permit tcp host x.x.251.5 eq domain any
access-list 101 permit udp host x.x.x.69 eq domain any
access-list 101 permit tcp host x.x.x.69 eq domain any
access-list 101 permit tcp any any eq 22
access-list 101 deny ip any any
You need to allow ICMP echoes in for you to be able to ping yourself.
Hope that helps - pls rate the post if it does.
Paresh
02-12-2006 11:30 AM
Hi Matthew,
Change your ACL so that it looks like this (you will have to remove it completely and re-add this):
access-list 101 permit udp any eq bootps any eq bootpc
access-list 101 deny ip 10.0.0.0 0.255.255.255 any
access-list 101 deny ip 172.16.0.0 0.15.255.255 any
access-list 101 deny ip 192.168.0.0 0.0.255.255 any
access-list 101 deny ip 192.168.1.0 0.0.0.255 any
access-list 101 deny ip 127.0.0.0 0.255.255.255 any
access-list 101 deny ip host 255.255.255.255 any
access-list 101 permit icmp any any echo !!!! NEW LINE
access-list 101 permit icmp any any echo-reply
access-list 101 permit icmp any any time-exceeded
access-list 101 permit icmp any any unreachable
access-list 101 permit tcp host x.x.x.x any
access-list 101 permit udp host x.x.251.5 eq domain any
access-list 101 permit tcp host x.x.251.5 eq domain any
access-list 101 permit udp host x.x.x.69 eq domain any
access-list 101 permit tcp host x.x.x.69 eq domain any
access-list 101 permit tcp any any eq 22
access-list 101 deny ip any any
You need to allow ICMP echoes in for you to be able to ping yourself.
Hope that helps - pls rate the post if it does.
Paresh
02-12-2006 11:35 AM
I should have researched echo and echo-reply more.
Thanks !!
Matthew
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