icmp weirdness
Hey folks, I've got an issue at work I'd like to run by you. I sent a request to cisco's forum but have yet to hear an answer from anyone. We have a Cisco 2610 router in Ireland. This router has 1 Ethernet connected to a local segment and s0 point-to-point frame relay going to chicago, Ill (sub interface). Heres the details on the Ireland router: Ethernet segment: e0's primary address is 132.158.132.252/24 (some hosts refuse to change addresses). e0's secondary is 10.43.0.1/16. Serial 0/0.1 is 10.126.43.2/24. All advertised by Eigrp. Chicago's router is: Ethernet segment is varibly subnetted 10.4.0.0/16. Serial 0/0.13 is 10.126.43.1/24. Once again, Eigrp is the routing protocol. There is a host on Ireland's lan with address 10.43.3.230/16. If I log into Ireland's router and issue ping 10.43.3.230, nothing happens. It just times out. If I log into Chicago's router and ping the same host, it replies fine. If I ping it from a host behind Chicago's router, it replies as well. If another host on 10.43.0.0/16 pings that host it replies fine. I can ping any of 3.230's neighbors no problem. Its just that Ireland's router wont ping it at all. show ip route verifies a route as directly connected. Has anyone heard of this? A bug? I can't verify all the way down because I don't have physical access to Ireland's lan (thank god) to put a sniffer up. We are trying to use this host for a second default route to a vpn box incase the frame relay ever fails (and it does... often). Sorry to drag this on. Thanks in advance. Dave Cooper, CCNA Littelfuse, Inc. _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: icmp weirdness
Whenever I can't ping - I trace route to see where it goes stupid. And then I do it a few more times and compare the routes to see if they're the same or not. >From both ends of course. Have you done this yet? Kevin Wigle - Original Message - From: "David Cooper" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Thursday, 01 March, 2001 00:17 Subject: icmp weirdness > Hey folks, > > I've got an issue at work I'd like to run by you. I sent a request to > cisco's forum but have yet to hear an answer from anyone. We have a Cisco > 2610 router in Ireland. This router has 1 Ethernet connected to a local > segment and s0 point-to-point frame relay going to chicago, Ill (sub > interface). Heres the details on the Ireland router: > > Ethernet segment: e0's primary address is 132.158.132.252/24 (some hosts > refuse to change addresses). e0's secondary is 10.43.0.1/16. > Serial 0/0.1 is 10.126.43.2/24. All advertised by Eigrp. > > > Chicago's router is: > > Ethernet segment is varibly subnetted 10.4.0.0/16. > Serial 0/0.13 is 10.126.43.1/24. Once again, Eigrp is the routing protocol. > > There is a host on Ireland's lan with address 10.43.3.230/16. > > If I log into Ireland's router and issue ping 10.43.3.230, nothing happens. > It just times out. If I log into Chicago's router and ping the same host, it > replies fine. If I ping it from a host behind Chicago's router, it replies as > well. If another host on 10.43.0.0/16 pings that host it replies fine. I > can ping any of 3.230's neighbors no problem. Its just that Ireland's router > wont ping it at all. show ip route verifies a route as directly connected. > > Has anyone heard of this? A bug? I can't verify all the way down because I > don't have physical access to Ireland's lan (thank god) to put a sniffer up. > > > We are trying to use this host for a second default route to a vpn box incase > the frame relay ever fails (and it does... often). > > Sorry to drag this on. > > Thanks in advance. > Dave Cooper, CCNA > Littelfuse, Inc. > > _ > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: icmp weirdness
David, A normal ping is being sourced from 132.158.132.252 to 10.43.3.230. You need to do a extended ping specifying 10.43.0.1 as the source. Type 'ping' then enter and enter the target address then enter for the following questions to take defaults. On the extended commands question answer Yes. The next question is the source address. Enter 10.43.0.1 and take the defaults for the rest. The ping should work. What is the default gateway on this 10.43.3.230 PC? If their default gateway is 10.43.0.1 it should work but if it's not and the PC has a static route for the 10.43.0.x with next hop of 10.43.0.1 then the ping response (echo-reply) is being sent to the default gateway address that PC has set. This is because it doesn't know how to get back to the 132.158.132.x network the ping (echo) came from. If you have the user at the PC do a traceroute (tracert on windows) to 132.158.132.152 what is first IP address returned? That is the first router it hits. The issue with secondary address's is that traffic generated from the router usually uses the primary IP address on the interfaces unless told not to. Routing protocols can have issues with secondarys. You should only use secondary address's for a short time while changes are being made if needed for the above reasons. If the 10.43.0.x network is the main network at this location now then make that the primary address on the interface and the other address with less users the secondary until they get their IP address changed. HTH, Erick --- David Cooper <[EMAIL PROTECTED]> wrote: > Hey folks, > > I've got an issue at work I'd like to run by you. I > sent a request to > cisco's forum but have yet to hear an answer from > anyone. We have a Cisco > 2610 router in Ireland. This router has 1 Ethernet > connected to a local > segment and s0 point-to-point frame relay going to > chicago, Ill (sub > interface). Heres the details on the Ireland > router: > > Ethernet segment: e0's primary address is > 132.158.132.252/24 (some hosts > refuse to change addresses). e0's secondary is > 10.43.0.1/16. > Serial 0/0.1 is 10.126.43.2/24. All advertised by > Eigrp. > > > Chicago's router is: > > Ethernet segment is varibly subnetted 10.4.0.0/16. > Serial 0/0.13 is 10.126.43.1/24. Once again, Eigrp > is the routing protocol. > > There is a host on Ireland's lan with address > 10.43.3.230/16. > > If I log into Ireland's router and issue ping > 10.43.3.230, nothing happens. > It just times out. If I log into Chicago's router > and ping the same host, it > replies fine. If I ping it from a host behind > Chicago's router, it replies as > well. If another host on 10.43.0.0/16 pings that > host it replies fine. I > can ping any of 3.230's neighbors no problem. Its > just that Ireland's router > wont ping it at all. show ip route verifies a route > as directly connected. > > Has anyone heard of this? A bug? I can't verify all > the way down because I > don't have physical access to Ireland's lan (thank > god) to put a sniffer up. > > > We are trying to use this host for a second default > route to a vpn box incase > the frame relay ever fails (and it does... often). > > Sorry to drag this on. > > Thanks in advance. > Dave Cooper, CCNA > Littelfuse, Inc. __ Do You Yahoo!? Get email at your own domain with Yahoo! Mail. http://personal.mail.yahoo.com/ _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: icmp weirdness
Hey, thanks for the help. In the frame relay network we have, hops are transparent kind of. Only the CPE is visable. I had established that the problem was occuring at the last router's ethernet interface. When I trace the routes out it just gets to that router and times out. What Erick B. pointed out was due to the fact that the primary address on e0 was not the same network that the host in question was on. This turns out to be the case. If I do an extended ping and source the packets from the secondary address, the machine responds without haste. I've requested that the administrator of the hosts over there build a static route to the foriegn network address to help out although I don't suspect it will help alot from an analytical point of view. :) Thanks for all the help! - Sorry for the delay in replies. Dave On Thursday 01 March 2001 00:17, David Cooper wrote: > Hey folks, > > I've got an issue at work I'd like to run by you. I sent a request to > cisco's forum but have yet to hear an answer from anyone. We have a Cisco > 2610 router in Ireland. This router has 1 Ethernet connected to a local > segment and s0 point-to-point frame relay going to chicago, Ill (sub > interface). Heres the details on the Ireland router: > > Ethernet segment: e0's primary address is 132.158.132.252/24 (some hosts > refuse to change addresses). e0's secondary is 10.43.0.1/16. > Serial 0/0.1 is 10.126.43.2/24. All advertised by Eigrp. > > > Chicago's router is: > > Ethernet segment is varibly subnetted 10.4.0.0/16. > Serial 0/0.13 is 10.126.43.1/24. Once again, Eigrp is the routing protocol. > > There is a host on Ireland's lan with address 10.43.3.230/16. > > If I log into Ireland's router and issue ping 10.43.3.230, nothing happens. > It just times out. If I log into Chicago's router and ping the same host, > it replies fine. If I ping it from a host behind Chicago's router, it > replies as well. If another host on 10.43.0.0/16 pings that host it > replies fine. I can ping any of 3.230's neighbors no problem. Its just > that Ireland's router wont ping it at all. show ip route verifies a route > as directly connected. > > Has anyone heard of this? A bug? I can't verify all the way down because I > don't have physical access to Ireland's lan (thank god) to put a sniffer > up. > > > We are trying to use this host for a second default route to a vpn box > incase the frame relay ever fails (and it does... often). > > Sorry to drag this on. > > Thanks in advance. > Dave Cooper, CCNA > Littelfuse, Inc. > > _ > FAQ, list archives, and subscription info: > http://www.groupstudy.com/list/cisco.html Report misconduct and > Nondisclosure violations to [EMAIL PROTECTED] _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
