Thanks for the ideas. I did try some of those things. I didn't know that you could tell if a device was a Frame Relay switch or router based on whether it sets the DE bit, though? And how would I know if the frame arrived with the DE bit set??
This was on a virtual lab. I didn't have access to the FR switch. I agree with you that it was acting funny. If I have time I'll go back and do some more testing, but I can't promise that I will have time. Thank-you very much for your inteest in the problem and your suggestions, though. Priscila [EMAIL PROTECTED] wrote: > > Hi Priscilla > > Can you put debug ip icmp in both R1 and R3 routers? or better > debug ip > packet detail. This is for checking if R3 is really sending six > icmp ttl > exceeded when traceroute is executed. > > Also, you can use ping with record option set instead > traceroute to see the > path. > > I'm suspecting that frame-relay switch is not configured with > frame-relay > switching, but this introduce several issues about ospf. Can > you check with > show ip ospf database that you have only three routers.? Also > you can check > if frame-relay switch router is really working as a switch > frame-relay > sending traffic from R1 marked with DE. If this arrive to R3 > without DE mean > that frame-relay switch is really routing ip traffic instead of > switching > frames. The same test must be done between R2 and R3 > > Another test should be send pings from 172.16.1.1 to > 172.16.2.2 with ttl > set to 1, 2 and 3. Debug ip packet detail in all routers must > help you to > identified what is wrong > > Is cdp active ? If yes, can you check neighbours of R3? You > must see only R1 > and R3 is router acting as fr-switch is working properly. > > > Please, could you update me with result of this issue ? I'm > very interesting > whit it. > > Regards > > Rafa > > > > -----Mensaje original----- > De: Priscilla Oppenheimer [mailto:[EMAIL PROTECTED]] > Enviado el: lunes 19 de agosto de 2002 20:27 > Para: [EMAIL PROTECTED] > Asunto: RE: Traceroute IP displays twice (previous post by Pri > [7:51633] > > > Hi Mark, etc. > > I never got a satisfactory explanation for my results with > Trace Route. In > my case, a particular router was claiming to be the first hop > and the second > hop. That's different from what we're seeing in the current > question, where > two different routers are claiming to be the first hop (due to > load > balancing). > > Here are the syptoms: > > r1#trace 172.16.2.2 > > Type escape sequence to abort. > Tracing the route to 172.16.2.2 > > 1 172.16.1.3 12 msec 12 msec 12 msec > 2 172.16.1.3 12 msec 8 msec 8 msec > 3 172.16.2.2 24 msec 20 msec 20 msec > > It's a frame-relay hub-and-spoke topology. I'm on one spoke > trying to trace > to another spoke through the hub. The trace succeeds. The > network is > working, but what's with the router replying twice? (It happens > if I go the > other way too.) > > The hub router is 172.16.1.3. Why is it sending back the dest > unreachable > twice? > > The topology is: > > R1------R3-----R2 > > > Here are my configs: > > r1 > ip subnet-zero > no ip icmp rate-limit unreachable > ! > interface Loopback0 > ip address 192.168.255.1 255.255.255.255 > ! > interface Ethernet0/0 > description to Cat 5K 3/1 > ip address 10.10.1.1 255.255.255.0 > half-duplex > ! > interface TokenRing0/0 > description in ring 1 > ip address 192.168.1.1 255.255.255.0 > ring-speed 16 > ! > interface Serial1/0 > ip address 172.16.1.1 255.255.255.0 > encapsulation frame-relay > ip ospf network point-to-point > frame-relay interface-dlci 133 > frame-relay lmi-type ansi > ! > router ospf 1 > log-adjacency-changes > network 10.10.1.0 0.0.0.255 area 0.0.0.0 > network 172.16.0.0 0.0.255.255 area 0.0.0.0 > network 192.168.1.0 0.0.0.255 area 0.0.0.0 > network 192.168.255.1 0.0.0.0 area 0.0.0.0 > ! > ip classless > > > > R3 > ip subnet-zero > no ip icmp rate-limit unreachable > ! > interface Loopback0 > ip address 192.168.255.3 255.255.255.255 > ! > interface Ethernet0/0 > description link to cat5k 3/3 > ip address 10.10.3.1 255.255.255.0 > half-duplex > ! > interface Serial1/0 > description Frame relay > no ip address > encapsulation frame-relay > no fair-queue > no frame-relay inverse-arp > frame-relay lmi-type ansi > ! > interface Serial1/0.1 point-to-point > description link to R1 > ip address 172.16.1.3 255.255.255.0 > ip ospf network point-to-point > frame-relay interface-dlci 331 > ! > interface Serial1/0.2 point-to-point > description link to R2 > ip address 172.16.2.3 255.255.255.0 > ip ospf network point-to-point > frame-relay interface-dlci 332 > ! > router ospf 1 > log-adjacency-changes > network 10.10.3.0 0.0.0.255 area 0.0.0.0 > network 172.16.0.0 0.0.255.255 area 0.0.0.0 > network 192.168.255.3 0.0.0.0 area 0.0.0.0 > ! > ip classless > > > R2 > ! > hostname r2 > ! > ip subnet-zero > no ip icmp rate-limit unreachable > ! > interface Loopback0 > ip address 192.168.255.2 255.255.255.255 > ! > interface Ethernet0/0 > description to Cat 5K 3/2 > ip address 10.10.2.1 255.255.255.0 > half-duplex > ! > interface TokenRing0/0 > ip address 192.168.2.1 255.255.255.0 > ring-speed 16 > ! > interface Serial1/0 > ip address 172.16.2.2 255.255.255.0 > encapsulation frame-relay > ip ospf network point-to-point > no fair-queue > frame-relay interface-dlci 233 > frame-relay lmi-type ansi > ! > router ospf 1 > log-adjacency-changes > network 10.10.2.0 0.0.0.255 area 0.0.0.0 > network 172.16.0.0 0.0.255.255 area 0.0.0.0 > network 192.168.2.0 0.0.0.255 area 0.0.0.0 > network 192.168.255.2 0.0.0.0 area 0.0.0.0 > ip classless > > > There's a Cisco router "in the cloud" acting as a Frame Relay > switch, > switching from DLCIs. I don't have its config. (This was a > virtual lab). > Thanks for any hints you can give me. > > Priscilla > > ________________________ > > Priscilla Oppenheimer > http://www.priscilla.com > > > Vicuna, Mark wrote: > > > > While we are on the topic.. I remember a post by Priscilla a > > few months > > ago now (I think) with a traceroute showing 2 path entries of > > the same > > ip. The result of the traceroute was not able to be > reproduced > > (I > > think). Anyone remember what the outcome of this was? > > > > > > The archives are not searchable at this point in time. > > > > > > Cheers > > Mark. > > > > > -----Original Message----- > > > From: Robert D. Cluett [mailto:[EMAIL PROTECTED]] > > > Sent: Monday, 19 August 2002 19:10 > > > To: [EMAIL PROTECTED] > > > Subject: Re: traceroute IP displays twice [7:51622] > > > > > > > > > Thanks Raj! > > > > > > ""Raj Santiago"" wrote in message > > > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > > > i should have included this part as well to the previous > > post : > > > > > > > > >1 172.26.1.13 20 msec > > > > 172.26.1.2 20 msec > > > > 172.26.1.13 20 msec > > > > > > > > The above indicates, of the two possible paths the router > > > has [172.26.1.2, > > > > 172.26.1.13] it has chosen the path 172.26.1.13. > ********************************************** > Noticia legal > Este mensaje electrsnico contiene informacisn de BT Ignite > Espaqa S.A.U. que > es privada y confidencial, siendo para el uso exclusivo de la > persona (s) o > entidades arriba mencionadas. Si usted no es el destinatario > seqalado, le > informamos que cualquier divulgacisn, copia, distribucisn o uso > de los > contenidos esta prohibida. Si usted ha recibido este mensaje > por error, por > favor borre su contenido lo antes posible. > Gracias. > > Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=51851&t=51823 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
