Interface name vs interface IP address
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From: Laughing Man on 22 Mar 2010 19:12 hello, Today due to my ISP gave me a new ip address and netmask. I changed the ip address on the Ethernet 1 interface but it would not even pink the gateway. I made sure that the default gateway was set correctly with the ip route 0.0.0.0 0.0.0.0 201.159.177.X command. After troubleshooting a few hours and being stumped it worked when I used the command ip route 0.0.0.0 0.0.0.0 Eth1. Why would using the interface name make a difference? Eth 1 configuration: (last octet replaced with X) interface Ethernet1 description Internet bandwidth 10240 ip address 201.159.177.X 255.255.255.252 ip access-group 10 in ip access-group 10 out ip nat outside ip route-cache flow duplex auto ! ip route 0.0.0.0 0.0.0.0 Ethernet1 Any thoughts? :-/ Thanx!
From: Doug McIntyre on 22 Mar 2010 22:57 Laughing Man <romantercero(a)gmail.com> writes: >Today due to my ISP gave me a new ip address and netmask. I changed >the ip address on the Ethernet 1 interface but it would not even pink >the gateway. I made sure that the default gateway was set correctly >with the ip route 0.0.0.0 0.0.0.0 201.159.177.X command. After >troubleshooting a few hours and being stumped it worked when I used >the command ip route 0.0.0.0 0.0.0.0 Eth1. Why would using the >interface name make a difference? >Eth 1 configuration: (last octet replaced with X) >interface Ethernet1 > description Internet > bandwidth 10240 > ip address 201.159.177.X 255.255.255.252 > ip access-group 10 in > ip access-group 10 out > ip nat outside > ip route-cache flow > duplex auto >! >ip route 0.0.0.0 0.0.0.0 Ethernet1 >Any thoughts? :-/ Your "fix" will be causing you problems after your router's ARP table fills up and falls down. I'd verify with your ISP that you two have your IP addressing correct, and your idea of your default route matches what they have setup for real. Mistakes happen with humans entering numbers. I'd also make sure that you had old info really cleared out. If you had two default routes, you might get every other one through. Or your access-groups are filtering out ICMP echo's, or something else.
From: Thrill5 on 22 Mar 2010 23:17
"Laughing Man" <romantercero(a)gmail.com> wrote in message news:0cc880ee-3258-4821-963a-fc9e1826e758(a)g11g2000yqe.googlegroups.com... > hello, > > Today due to my ISP gave me a new ip address and netmask. I changed > the ip address on the Ethernet 1 interface but it would not even pink > the gateway. I made sure that the default gateway was set correctly > with the ip route 0.0.0.0 0.0.0.0 201.159.177.X command. After > troubleshooting a few hours and being stumped it worked when I used > the command ip route 0.0.0.0 0.0.0.0 Eth1. Why would using the > interface name make a difference? > > Eth 1 configuration: (last octet replaced with X) > > interface Ethernet1 > description Internet > bandwidth 10240 > ip address 201.159.177.X 255.255.255.252 > ip access-group 10 in > ip access-group 10 out > ip nat outside > ip route-cache flow > duplex auto > ! > > ip route 0.0.0.0 0.0.0.0 Ethernet1 > > Any thoughts? :-/ > > Thanx! Unless you have a mistake in the info you posted..... If your default route "0.0.0.0 0.0.0.0 201.159.177.X" is the address of YOUR router, you want the default to point to ISP's router which is X plus or minus 1. Pointing the default to yourself won't work. |