RE: Frame-relay map instead of static route

From: Antonio Soares (amsoares@netcabo.pt)
Date: Thu Aug 02 2007 - 18:13:47 ART


Interesting... But it seems it has to do with CEF and maybe the IOS release.
See bellow what i got with 12.4.10:

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
With CEF disabled i cannot ping anything:
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
R5#sh fram map
Serial0/0 (up): ip 4.4.4.4 dlci 504(0x1F8,0x7C80), static,
              CISCO, status defined, active
Serial0/0 (up): ip 155.1.0.4 dlci 504(0x1F8,0x7C80), static,
              broadcast,
              CISCO, status defined, active
Serial0/0 (up): ip 155.1.146.4 dlci 504(0x1F8,0x7C80), static,
              CISCO, status defined, active
R5#
R5#
R5#sh ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2
       i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
       ia - IS-IS inter area, * - candidate default, U - per-user static
route
       o - ODR, P - periodic downloaded static route

Gateway of last resort is not set

     155.1.0.0/24 is subnetted, 1 subnets
C 155.1.0.0 is directly connected, Serial0/0
R5#
R5#ping 4.4.4.4

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 4.4.4.4, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
R5#
R5#ping 155.1.146.4

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 155.1.146.4, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
R5#
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
With CEF enabled i'm able to ping both addresses:
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
R5#
R5#conf t
Enter configuration commands, one per line. End with CNTL/Z.
R5(config)#ip cef
R5(config)#end
R5#
R5#
R5#
*Mar 1 20:30:42.300: %SYS-5-CONFIG_I: Configured from console by console
R5#
R5#ping 4.4.4.4

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 4.4.4.4, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/30/32 ms
R5#
R5#ping 155.1.146.4

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 155.1.146.4, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/31/32 ms
R5#
R5#
R5#sh ip cef
Prefix Next Hop Interface
0.0.0.0/0 drop Null0 (default route handler entry)
0.0.0.0/32 receive
4.4.4.4/32 4.4.4.4 Serial0/0
155.1.0.0/24 attached Serial0/0
155.1.0.0/32 receive
155.1.0.4/32 155.1.0.4 Serial0/0
155.1.0.5/32 receive
155.1.0.255/32 receive
155.1.146.4/32 155.1.146.4 Serial0/0
224.0.0.0/4 drop
224.0.0.0/24 receive
255.255.255.255/32 receive
R5#
++++++++++++++++++++

Regards,

Antonio Soares
CCIE #18473, CCNP, CCIP

-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of Bit
Gossip
Sent: quinta-feira, 2 de Agosto de 2007 19:18
To: ccielab@groupstudy.com
Subject: Frame-relay map instead of static route

Gorup,
I have no explanation for the following behavior:

lo0 4.4.4.4/32
                                R4 ---- dlci 405 -------- fr ------ dlci
504---- R5
f0/0 155.1.146.4/24

R5 has no route to R4 lo0 nor to R4 f0/0. Instead it has frame-relay static
mapping for these 2 destination.

Understandably R5 can NOT ping R4 lo0
what I can NOT understand is how does it manage to ping R4 f0/0

<<<<<<<<< R5

interface Serial0/0
 ip address 155.1.0.5 255.255.255.0
 encapsulation frame-relay
 no fair-queue
 clock rate 128000
 frame-relay map ip 4.4.4.4 504 broadcast
 frame-relay map ip 155.1.0.4 504 broadcast
 frame-relay map ip 155.1.146.4 504 broadcast
 no frame-relay inverse-arp
end

R5#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP

Gateway of last resort is not set

     155.1.0.0/24 is subnetted, 1 subnets
C 155.1.0.0 is directly connected, Serial0/0
     5.0.0.0/32 is subnetted, 1 subnets
C 5.5.5.5 is directly connected, Loopback0
R5#show frame-relay map
Serial0/0 (up): ip 4.4.4.4 dlci 504(0x1F8,0x7C80), static,
              broadcast,
              CISCO, status defined, active
Serial0/0 (up): ip 155.1.0.4 dlci 504(0x1F8,0x7C80), static,
              broadcast,
              CISCO, status defined, active
Serial0/0 (up): ip 155.1.146.4 dlci 504(0x1F8,0x7C80), static,
              broadcast,
              CISCO, status defined, active
R5#ping 155.1.146.4

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 155.1.146.4, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/31/32 ms
R5#ping 4.4.4.4

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 4.4.4.4, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)



This archive was generated by hypermail 2.1.4 : Sat Sep 01 2007 - 11:32:09 ART