Nice job Frank!
Sent from my Verizon Wireless BlackBerry Regards, Joe Astorino - CCIE #24347 Sr. Technical Instructor - IPexpert Mailto: [email protected] Telephone: +1.810.326.1444 Live Assistance, Please visit: www.ipexpert.com/chat eFax: +1.810.454.0130 IPexpert is a premier provider of Self-Study Workbooks, Video on Demand, Audio Tools, Online Hardware Rental and Classroom Training for the Cisco CCIE (R&S, Voice, Security & Service Provider) certification(s) with training locations throughout the United States, Europe, South Asia and Australia. Be sure to visit our online communities at www.ipexpert.com/communities and our public website at www.ipexpert.com -----Original Message----- From: Frank <[email protected]> Date: Sun, 11 Apr 2010 20:11:35 To: Bryan Bartik<[email protected]> Cc: [email protected]<[email protected]> Subject: Re: [OSL | CCIE_RS] Vol 1 - lab 8 - frame relay question Hi Bryan, Briljant! R2#sh ip cef 150.100.100.5 detail 150.100.100.5/32, version 64, epoch 0, connected, cached adjacency 150.100.100.5 0 packets, 0 bytes via 150.100.100.5, Serial2/0.25, 0 dependencies next hop 150.100.100.5, Serial2/0.25 valid cached adjacency R2#sh ip cef 150.100.100.6 detail 150.100.100.6/32, version 32, epoch 0, cached adjacency 150.100.100.6 0 packets, 0 bytes via 150.100.100.6, Serial2/0.26, 0 dependencies next hop 150.100.100.6, Serial2/0.26 valid cached adjacency So the CEF table is not only build by using the only RIB, but also it takes details from the FR config into account. To continue the experiment: R2#ping 150.100.100.5 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 150.100.100.5, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 56/56/60 ms R2#ping 150.100.100.6 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 150.100.100.6, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 56/57/60 ms R2#conf t Enter configuration commands, one per line. End with CNTL/Z. R2(config)#no ip cef R2(config)#end R2#ping 150.100.100.5 *Mar 2 20:09:25.987: %SYS-5-CONFIG_I: Configured from console by console R2#ping 150.100.100.5 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 150.100.100.5, timeout is 2 seconds: .!.!. Success rate is 40 percent (2/5), round-trip min/avg/max = 56/56/56 ms R2#ping 150.100.100.6 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 150.100.100.6, timeout is 2 seconds: .!.!. Success rate is 40 percent (2/5), round-trip min/avg/max = 56/56/56 ms R2# Without CEF, the routing table is consulted for next hop determination, and it has two identical routes for 150.100.100.0/24, so with per packet load balancing; half of the pings is lost! Regards, Frank Bryan Bartik schreef: > Frank, > > This is a function of CEF, which actually performs the forwarding. > Look at the CEF entries for the next hop and you will see adjacencies > for each interface. Turn off CEF and then test some more :) > > On Thu, Apr 8, 2010 at 12:43 PM, Frank <[email protected] > <mailto:[email protected]>> wrote: > > > All, > > I'm still struggling with some of the frame-relay concept. In the > DSG two multipoint sub-interfaces are used with the same IP subnet: > > interface Serial2/0.25 multipoint > ip address 150.100.100.2 255.255.255.0 > ip rip authentication mode md5 > ip rip authentication key-chain R2R5 > frame-relay map ip 150.100.100.5 205 broadcast > ! > interface Serial2/0.26 multipoint > ip address 150.100.100.2 255.255.255.0 > ip rip authentication mode md5 > ip rip authentication key-chain R2R6 > frame-relay map ip 150.100.100.6 206 broadcast > > > But, when we look at the routing table: > > R2#sh ip route 150.100.100.5 > Routing entry for 150.100.100.0/24 <http://150.100.100.0/24> > Known via "connected", distance 0, metric 0 (connected, via > interface) > Redistributing via rip > Advertised by rip > Routing Descriptor Blocks: > * directly connected, via Serial2/0.26 > Route metric is 0, traffic share count is 1 > directly connected, via Serial2/0.25 > Route metric is 0, traffic share count is 1 > > R2#sh ip route 150.100.100.6 > Routing entry for 150.100.100.0/24 <http://150.100.100.0/24> > Known via "connected", distance 0, metric 0 (connected, via > interface) > Redistributing via rip > Advertised by rip > Routing Descriptor Blocks: > * directly connected, via Serial2/0.26 > Route metric is 0, traffic share count is 1 > directly connected, via Serial2/0.25 > Route metric is 0, traffic share count is 1 > > two identical routes exist towards a next hop. > > The thing that I still can't grasp is the relation between the IP > routing table and the frame-relay map. > From the routing table point of view there are two identical paths > towards the next hop, yet always the correct path seems to be > picked. How? > > Regards, > > Frank > > > > > _______________________________________________ > For more information regarding industry leading CCIE Lab training, > please visit www.ipexpert.com <http://www.ipexpert.com> > > > > > -- > Bryan Bartik > CCIE #23707 (R&S, SP), CCNP > Sr. Support Engineer - IPexpert, Inc. > URL: http://www.IPexpert.com _______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com _______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com
