hhmmmmm........ learn something new every day. thanks. that still gets back to how ip unnumbered "really" works, as opposed to how most of us "think" it works. RFC 1812 specifically talks about using the RID as the interface address:
"this memo has adopted an alternate scheme, which has been invented multiple times but which is probably originally attributable to Phil Karn. In this scheme, a router that has unnumbered point to point lines also has a special IP address, called a router-id in this memo. The router-id is one of the router's IP addresses (a router is required to have at least one IP address). This router-id is used as if it is the IP address of all unnumbered interfaces." whaddaya know - I did recall correctly :-> so it would appear that in the Cisco implementation, at least, for unnumbered interfaces, the reference interface ip also becomes the RID for purposes of unnumbered? So what does this discovery do to the proposition that one "should" use a loopback as the reference for unnumbered interfaces because loopbacks are "never down"??? interesting discussion. learned something new. Chuck > > ""richard dumoulin"" wrote in message > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > No prob, see below. > > > > > > > > RB#sh run > > Building configuration... > > > > Current configuration: > > ! > > version 11.2 > > no service password-encryption > > no service udp-small-servers > > no service tcp-small-servers > > ! > > hostname RB > > ! > > enable password cisco > > ! > > no ip domain-lookup > > ! > > interface Ethernet0 > > ip address 192.168.1.1 255.255.255.0 > > ! > > interface Serial0 > > ip unnumbered Ethernet0 > > ! > > interface Serial1 > > no ip address > > shutdown > > ! > > interface Serial2 > > no ip address > > shutdown > > ! > > interface Serial3 > > no ip address > > shutdown > > ! > > interface Serial4 > > no ip address > > shutdown > > ! > > interface Serial5 > > no ip address > > shutdown > > ! > > interface Serial6 > > no ip address > > shutdown > > ! > > interface Serial7 > > no ip address > > shutdown > > ! > > interface Serial8 > > no ip address > > shutdown > > ! > > interface Serial9 > > no ip address > > shutdown > > ! > > interface BRI0 > > no ip address > > shutdown > > ! > > no ip classless > > ip route 0.0.0.0 0.0.0.0 Serial0 > > ! > > line con 0 > > line aux 0 > > line vty 0 4 > > password cisco > > login > > ! > > end > > > > RB#172.16.1.1 > > Trying 172.16.1.1 ... Open > > > > > > User Access Verification > > > > Password: > > RA>en > > Password: > > RA#sh run > > Building configuration... > > > > Current configuration : 801 bytes > > ! > > version 12.2 > > service timestamps debug uptime > > service timestamps log uptime > > no service password-encryption > > ! > > hostname RA > > ! > > enable password cisco > > ! > > memory-size iomem 10 > > ip subnet-zero > > ! > > ! > > no ip domain-lookup > > ! > > ip ssh time-out 120 > > ip ssh authentication-retries 3 > > ! > > call rsvp-sync > > ! > > ! > > ! > > ! > > ! > > ! > > ! > > ! > > interface Ethernet0/0 > > ip address 172.16.1.1 255.255.0.0 > > no keepalive > > half-duplex > > ! > > interface Serial0/0 > > no ip address > > shutdown > > ! > > interface Serial0/1 > > no ip address > > shutdown > > ! > > interface Serial0/2 > > ip unnumbered Ethernet0/0 > > clockrate 2000000 > > ! > > interface Serial0/3 > > no ip address > > shutdown > > ! > > ip classless > > ip route 0.0.0.0 0.0.0.0 Serial0/2 > > no ip http server > > ! > > ! > > ! > > dial-peer cor custom > > ! > > ! > > ! > > ! > > ! > > line con 0 > > line aux 0 > > line vty 0 4 > > password cisco > > login > > line vty 5 15 > > login > > ! > > no scheduler allocate > > end > > > > RA# > > RB# > > [Resuming connection 1 to 172.16.1.1 ... ] > > > > RA# > > RA# > > RB#172.16.1.1 > > Trying 172.16.1.1 ... Open > > > > > > User Access Verification > > > > Password: > > RA>en > > Password: > > RA#ping 192.168.1.1 > > > > Type escape sequence to abort. > > Sending 5, 100-byte ICMP Echos to 192.168.1.1, timeout is 2 seconds: > > !!!!! > > Success rate is 100 percent (5/5), round-trip min/avg/max = 4/4/8 ms > > RA# > > RB#term mon > > % Console already monitors > > RB# > > %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0, changed state > to > > down > > [Resuming connection 2 to 172.16.1.1 ... ] > > > > RA#ping 192.168.1.1 > > > > Type escape sequence to abort. > > Sending 5, 100-byte ICMP Echos to 192.168.1.1, timeout is 2 seconds: > > !!!!! > > Success rate is 100 percent (5/5), round-trip min/avg/max = 4/4/8 ms > > RA#ping 192.168.1.1 > > > > Type escape sequence to abort. > > Sending 5, 100-byte ICMP Echos to 192.168.1.1, timeout is 2 seconds: > > !!!!! > > Success rate is 100 percent (5/5), round-trip min/avg/max = 4/5/8 ms > > RA# > > RB#conf t > > Enter configuration commands, one per line. End with CNTL/Z. > > RB(config)#int e0 > > RB(config-if)#shut > > RB(config-if)# > > %LINK-5-CHANGED: Interface Ethernet0, changed state to administratively > > down^Z > > RB#d > > %SYS-5-CONFIG_I: Configured from console by consoleeb ip pa det > > IP packet debugging is on (detailed) > > RB# > > [Resuming connection 2 to 172.16.1.1 ... ] > > > > RA# > > IP: s=192.168.1.1 (local), d=172.16.1.1 (Serial0), len 40, sending > > TCP src=11001, dst=23, seq=3044171494, ack=4024004928, win=4288 ACK > > IP: s=192.168.1.1 (local), d=172.16.1.1 (Serial0), len 42, sending > > TCP src=11001, dst=23, seq=3044171494, ack=4024004928, win=4288 ACK > PSH > > IP: s=172.16.1.1 (Serial0), d=192.168.1.1 (Serial0), len 42, rcvd 3 > > TCP src=23, dst=11001, seq=4024004928, ack=3044171496, win=4058 ACK > PSH > > IP: s=172.16.1.1 (Serial0), d=192.168.1.1 (Serial0), len 43, rcvd 3 > > TCP src=23, dst=11001, seq=4024004930, ack=3044171496, win=4058 ACK > PSH > > IP: s=192.168.1.1 (local), d=172.16.1.1 (Serial0), len 40, sending > > TCP src=11001, dst=23, seq=3044171496, ack=4024004933, win=4283 > ACKping > > 192.168.1.1 > > > > Type escape sequence to abort. > > Sending 5, 100-byte ICMP Echos to 192.168.1.1, timeout is 2 seconds: > > !! > > IP: s=192.168.1.1 (local), d=172.16.1.1 (Serial0), len 41, sending > > TCP src=11001, dst=23, seq=3044171496, ack=4024004933, win=4283 ACK > PSH > > IP: s=172.16.1.1 (Serial0), d=192.168.1.1 (Serial0), len 56, rcvd 3 > > TCP src=23, dst=11001, seq=4024004933, ack=3044171497, win=4057 ACK > PSH > > IP: s=192.168.1.1 (local), d=172.16.1.1 (Serial0), len 40, sending > > TCP src=11001, dst=23, seq=3044171497, ack=4024004949, win=4267 ACK > > IP: s=192.168.1.1 (local), d=172.16.1.1 (Serial0), len 42, sending > > TCP s!!! > > Success rate is 100 percent (5/5), round-trip min/avg/max = 12/16/20 ms > > RA#rc=11001, dst=23, seq=3044171497, ack=4024004949, win=4267 ACK PSH > > IP: s=172.16.1.1 (Serial0), d=192.168.1.1 (Serial0), len 42, rcvd 3 > > TCP src=23, dst=11001, seq=4024004949, ack=3044171499, win=4055 ACK > PSH > > IP: s=172.16.1.1 (Serial0), d=192.168.1.1 (Serial0), len 142, rcvd 3 > > TCP src=23, dst=11001, seq=4024004951, ack=3044171499, win=4055 ACK > PSH > > IP: s=172.16.1.1 (Serial0), d=192.168.1.1 (Serial0), len 42, rcvd 3 > > TCP src=23, dst=11001, seq=4024005053, ack=3044171499, win=4055 ACK > PSH > > IP: s=172.16.1.1 (Serial0), d=192.168.1.1 (Serial0), len 100, rcvd 3 > > ICMP type=8, code=0 > > IP: s=192.168.1.1 (local), d=172.16.1.1 (Serial0), len 100, sending > > ICMP type=0, code=0 > > IP: s=172.16.1.1 (Serial0), d=192.168.1.1 (Serial0), len 41, rcvd 3 > > TCP src=23, dst=11001, seq=4024005055, ack=3044171499, win=4055 ACK > PSH > > IP: s=172.16.1.1 (Serial0), d=192.168.1.1 (Serial0), len 100, rcvd 3 > > ICMP type=8, code=0 > > IP: s=192.168.1.1 (local), d=172.16.1.1 (Serial0), len 100, sending > > ICMP type=0, code=0 > > IP: s=172.16.1.1 (Serial0), d=192.168.1.1 (Serial0), len 41, rcvd 3 > > TCP src=23, dst=11001, seq=4024005056, ack=3044171499, win=4055 ACK > PSH > > IP: s=172.16.1.1 (Serial0), d=192.168.1.1 (Serial0), len 100, rcvd 3 > > ICMP type=8, code=0 > > IP: s=192.168.1.1 (local), d=172.16.1.1 (Serial0), len 100, sending > > ICMP type=0, code=0 > > IP: s=192.168.1.1 (local), d=172.16.1.1 (Serial0), len 40, sending > > TCP src=11001, dst=23, seq=3044171499, ack=4024005057, win=4159 ACK > > IP: s=172.16.1.1 (Serial0), d=192.168.1.1 (Serial0), len 41, rcvd 3 > > TCP src=23, dst=11001, seq=4024005057, ack=3044171499, win=4055 ACK > PSH > > IP: s=172.16.1.1 (Serial0), d=192.168.1.1 (Serial0), len 100, rcvd 3 > > ICMP type=8, code=0 > > IP: s=192.168.1.1 (local), d=172.16.1.1 (Serial0), len 100, sending > > ICMP type=0, code=0 > > IP: s=172.16.1.1 (Serial0), d=192.168.1.1 (Serial0), len 41, rcvd 3 > > TCP src=23, dst=11001, seq=4024005058, ack=3044171499, win=4055 ACK > PSH > > IP: s=172.16.1.1 (Serial0), d=192.168.1.1 (Serial0), len 100, rcvd 3 > > ICMP type=8, code=0 > > IP: s=192.168.1.1 (local), d=172.16.1.1 (Serial0), len 100, sending > > ICMP type=0, code=0 > > IP: s=172.16.1.1 (Serial0), d=192.168.1.1 (Serial0), len 41, rcvd 3 > > TCP src=23, dst=11001, seq=4024005059, ack=3044171499, win=4055 ACK > PSH > > IP: s=172.16.1.1 (Serial0), d=192.168.1.1 (Serial0), len 118, rcvd 3 > > TCP src=23, dst=11001, seq=4024005060, ack=3044171499, win=4055 ACK > PSH > > IP: s=192.168.1.1 (local), d=172.16.1.1 (Serial0), len 40, sending > > TCP src=11001, dst=23, seq=3044171499, ack=4024005138, win=4078 ACK Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=49508&t=49347 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
