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RE: Redistribution Question posted 05/17/2001
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Jim,

Good tip on the hosts routes, but I think you may have your VLSMs and FLSMs
mixed up in the paragraph below.

You certainly can summarize shorter VLSM to longer FLSM...

SY


-----Original Message-----
From: Jim Graves [mailto:jtg@xxxxxxxxxx]
Sent: Thursday, May 17, 2001 10:38 AM
To: Wei Man; ccielab@xxxxxxxxxxxxxx
Subject: Re: Redistribution Question


You're able to reach R3 and R5 because R6 has host routes for them.  That 
happens when using ip ospf network point-to-multipoint; the hub puts in 
host routes for the other spokes so the spokes can reach each other.  These 
host routes are injected into RIP.  R9 accepts them because a mask isn't 
needed when the address is obviously a host address (as .3 and .5 are).

R9 isn't seeing 170.150.43.0/28 because of a classic VLSM/FLSM 
redistribution problem.  RIP is a classful protocol.  So it only 
understands full classful networks, host routes, and subnets of a network 
with the same mask as its interface (in other words, if a RIP router has 
170.150.69.4/30, it will assume that any other subnet of the class B 
170.150.0.0 is also a /30).

If the VLSM (OSPF) network mask is longer than the FLSM (RIP) mask, the 
usual solution is to summarize the VLSM route to the FLSM's mask 
length.  But you have the opposite situation.  The FLSM mask is longer than 
the VLSM mask.  When that happens, you can't use summarization.  When the 
FLSM mask is longer than the VLSM mask, your only options are (a) static 
routes, or (b) injecting a default route.

Jim

At 11:22 PM 5/16/2001 -0700, Wei Man wrote:
>Hi,
>I am running problem using redistribute connected
>under router rip
>
>Whatever I did, the connected route never come up
>under rip
>
>here is diagram
>
>                   R3
>                   |
>                   |
>R4<----------Frame Relay Cloud <----------->R6
>                   |                          |
>                   |                          |
>                   R5                        R9
>
>where R4 is Hub and using mask 28 and R6,R3 and R9 is
>spoke using mask 28 and using OSPF as routing protocol
>
>R4 serial 0 connect to Frame-Relay Switch and
>R6 serial 0 connect to Frame-Relay Switch
>R3 serial 0 connect to Frame-Relay Switch
>R5 serial 0 connect to Frame-Relay Switch
>
>R6 and R9 running RIP and link between R6 and R9
>using mask 30
>
>I am be able to ping serial 0 of R5 and serial 0 of
>R3 from R9 and the route to reach it appear on R9
>
>I am NOT be able to ping R6 Serial 0 and
>R4 serial 0 from R9, even though I already put
>redistribute connected under router rip (No Route to
>Serial 0 of R6 and Serial 0 of R4)
>
>here is the complete config form R4, R6 and R9
>
>R9 Config
>R9#sh run
>Building configuration...
>
>Current configuration:
>!
>version 12.0
>no service pad
>service timestamps debug uptime
>service timestamps log uptime
>no service password-encryption
>!
>hostname R9
>!
>!
>ip subnet-zero
>no ip domain-lookup
>!
>!
>controller T1 0
>!
>!
>interface Loopback120
>  ip address 199.1.0.9 255.255.255.0
>  no ip directed-broadcast
>!
>interface Loopback121
>  ip address 199.1.1.9 255.255.255.0
>  no ip directed-broadcast
>!
>interface Loopback122
>  ip address 199.1.2.9 255.255.255.0
>  no ip directed-broadcast
>!
>interface Loopback123
>  ip address 199.1.3.9 255.255.255.0
>  no ip directed-broadcast
>!
>interface Loopback124
>  ip address 199.1.4.9 255.255.255.0
>  no ip directed-broadcast
>!
>interface Loopback125
>  ip address 199.1.5.9 255.255.255.0
>  no ip directed-broadcast
>!
>interface Loopback126
>  ip address 199.1.6.9 255.255.255.0
>  no ip directed-broadcast
>!
>interface Loopback127
>  ip address 199.1.7.9 255.255.255.0
>  no ip directed-broadcast
>!
>interface Loopback128
>  ip address 199.1.8.9 255.255.255.0
>  no ip directed-broadcast
>!
>interface Loopback129
>  ip address 199.1.9.9 255.255.255.0
>  no ip directed-broadcast
>!
>interface Ethernet0
>  no ip address
>  no ip directed-broadcast
>  shutdown
>!
>interface Serial0
>  ip address 170.150.69.5 255.255.255.252
>  no ip directed-broadcast
>!
>interface Serial1
>  no ip address
>  no ip directed-broadcast
>  shutdown
>!
>interface FR-ATM20
>  no ip address
>  no ip directed-broadcast
>  shutdown
>!
>router rip
>  timers basic 180 360 360 420
>  network 170.150.0.0
>  network 199.1.0.0
>  network 199.1.1.0
>  network 199.1.2.0
>  network 199.1.3.0
>  network 199.1.4.0
>  network 199.1.5.0
>  network 199.1.6.0
>  network 199.1.7.0
>  network 199.1.8.0
>  network 199.1.9.0
>!
>ip classless
>!
>alias exec c conf t
>alias exec ir show ip route
>alias exec x show ipx route
>alias exec o show ip ospf
>alias exec e show ip eigrp
>alias exec b show ip bgp
>alias exec ib show ip int brief
>alias exec xb show ipx int brief
>alias exec xs show ipx servers
>alias exec d clear ip route *
>alias exec q clear ip bgp *
>alias exec crs copy run start
>!
>line con 0
>  transport input none
>line aux 0
>line vty 0 4
>  privilege level 15
>  login
>!
>!
>voice-port 1/1
>  timeouts call-disconnect 0
>!
>voice-port 1/2
>  timeouts call-disconnect 0
>!
>voice-port 1/3
>  timeouts call-disconnect 0
>!
>voice-port 1/4
>  timeouts call-disconnect 0
>!
>voice-port 1/6
>  timeouts call-disconnect 0
>  timing dialout-delay 1000
>!
>end
>
>R9#sh ip ro
>Codes: C - connected, S - static, I - IGRP, 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, E - EGP
>        i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS
>level-2, * - candidate default
>        U - per-user static route, o - ODR
>
>Gateway of last resort is not set
>
>      170.150.0.0/16 is variably subnetted, 8 subnets,
>2 masks
>R       170.150.58.4/30 [120/7] via 170.150.69.6,
>00:01:04, Serial0
>R       170.150.43.5/32 [120/7] via 170.150.69.6,
>00:01:04, Serial0
>R       170.150.43.3/32 [120/7] via 170.150.69.6,
>00:01:04, Serial0
>R       170.150.45.4/30 [120/7] via 170.150.69.6,
>00:01:04, Serial0
>R       170.150.7.7/32 [120/7] via 170.150.69.6,
>00:01:04, Serial0
>R       170.150.3.3/32 [120/7] via 170.150.69.6,
>00:01:04, Serial0
>R       170.150.78.7/32 [120/7] via 170.150.69.6,
>00:01:04, Serial0
>C       170.150.69.4/30 is directly connected, Serial0
>C    199.1.9.0/24 is directly connected, Loopback129
>C    199.1.8.0/24 is directly connected, Loopback128
>C    199.1.3.0/24 is directly connected, Loopback123
>C    199.1.2.0/24 is directly connected, Loopback122
>R    160.60.0.0/16 [120/7] via 170.150.69.6, 00:01:05,
>Serial0
>C    199.1.1.0/24 is directly connected, Loopback121
>C    199.1.0.0/24 is directly connected, Loopback120
>C    199.1.7.0/24 is directly connected, Loopback127
>C    199.1.6.0/24 is directly connected, Loopback126
>C    199.1.5.0/24 is directly connected, Loopback125
>C    199.1.4.0/24 is directly connected, Loopback124
>R9#
>
>
>R6 Config
>
>R6#sh run
>Building configuration...
>
>Current configuration:
>!
>version 12.1
>service timestamps debug uptime
>service timestamps log uptime
>no service password-encryption
>!
>hostname R6
>!
>!
>!
>!
>!
>!
>ip subnet-zero
>no ip domain-lookup
>!
>cns event-service server
>!
>!
>!
>!
>!
>interface Loopback10
>  ip address 170.150.60.6 255.255.255.0
>  ip ospf network point-to-point
>!
>interface Loopback20
>  ip address 170.150.6.6 255.255.255.192
>  ip ospf network point-to-point
>!
>interface Loopback100
>  ip address 217.1.6.1 255.255.255.0
>!
>interface Serial0
>  ip address 170.150.43.6 255.255.255.240
>  encapsulation frame-relay
>  ip ospf message-digest-key 1 md5 cisco
>  ip ospf network point-to-multipoint
>  ip ospf hello-interval 20
>  ip ospf priority 0
>  frame-relay map ip 170.150.43.3 604 broadcast
>  frame-relay map ip 170.150.43.4 604 broadcast
>  frame-relay map ip 170.150.43.5 604 broadcast
>  frame-relay map ip 170.150.43.6 604 broadcast
>  frame-relay lmi-type ansi
>!
>interface Serial1
>  ip address 170.150.69.6 255.255.255.252
>  clockrate 2000000
>!
>interface TokenRing0
>  ip address 170.150.67.6 255.255.255.0
>  ring-speed 4
>!
>router ospf 10
>  area 0 authentication message-digest
>  area 0 range 170.150.6.0 255.255.255.192
>  area 0 range 170.150.43.0 255.255.255.0
>  area 6 range 170.150.60.0 255.255.255.0
>  redistribute connected metric-type 1 subnets
>route-map inject_conn_rip_to_ospf
>  redistribute rip metric 65 metric-type 1 subnets
>route-map inject_rip_to_ospf
>  passive-interface Serial1
>  passive-interface TokenRing0
>  network 170.150.6.0 0.0.0.63 area 0
>  network 170.150.43.6 0.0.0.0 area 0
>  network 170.150.60.0 0.0.0.255 area 6
>!
>router rip
>  timers basic 180 360 360 420
>  redistribute connected route-map
>inject_conn_ospf_to_rip
>  redistribute ospf 10 metric 7 route-map
>inject_ospf_to_rip
>  passive-interface Loopback10
>  passive-interface Loopback20
>  passive-interface Serial0
>  network 170.150.0.0
>  default-metric 1
>  distribute-list 20 in Serial1
>!
>ip classless
>no ip http server
>!
>!
>ip access-list standard inject_conn_ospf_to_rip
>ip access-list standard inject_conn_rip_to_ospf
>  permit 170.150.69.4 0.0.0.3
>ip access-list standard rdr_rip_ospf
>  permit 199.1.0.0 0.0.255.255
>access-list 20 deny   199.1.1.0 0.0.254.255
>access-list 20 permit any
>route-map inject_rip_to_ospf permit 10
>  match ip address rdr_rip_ospf
>!
>route-map inject_ospf_to_rip deny 10
>  match ip address rdr_rip_ospf
>!
>route-map inject_ospf_to_rip permit 20
>!
>route-map inject_conn_rip_to_ospf permit 10
>  match ip address inject_conn_rip_to_ospf
>!
>route-map inject_conn_ospf_to_rip permit 10
>  match interface Serial0
>!
>!
>alias exec c conf t
>alias exec ir show ip route
>alias exec x show ipx route
>alias exec o show ip ospf
>alias exec e show ip eigrp
>alias exec b show ip bgp
>alias exec ib show ip int brief
>alias exec xb show ipx int brief
>alias exec xs show ipx servers
>alias exec d clear ip route *
>alias exec q clear ip bgp *
>alias exec crs copy run start
>!
>line con 0
>  transport input none
>line aux 0
>line vty 0 4
>  privilege level 15
>  login
>!
>end
>
>R6#sh ip ro
>Codes: C - connected, S - static, I - IGRP, 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, E - EGP
>        i - IS-IS, 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
>
>      170.150.0.0/16 is variably subnetted, 21 subnets,
>5 masks
>C       170.150.60.0/24 is directly connected,
>Loopback10
>O IA    170.150.58.4/30 [110/192] via 170.150.43.4,
>00:13:00, Serial0
>O       170.150.43.5/32 [110/128] via 170.150.43.4,
>00:13:00, Serial0
>O IA    170.150.47.0/24 [110/65] via 170.150.43.4,
>00:13:00, Serial0
>O       170.150.43.4/32 [110/64] via 170.150.43.4,
>00:13:00, Serial0
>O       170.150.43.3/32 [110/128] via 170.150.43.4,
>00:13:00, Serial0
>O       170.150.45.4/30 [110/1849] via 170.150.43.4,
>00:13:01, Serial0
>C       170.150.43.0/28 is directly connected, Serial0
>O IA    170.150.33.0/24 [110/129] via 170.150.43.4,
>00:13:01, Serial0
>O IA    170.150.30.0/24 [110/138] via 170.150.43.4,
>00:13:01, Serial0
>O IA    170.150.14.0/24 [110/89] via 170.150.43.4,
>00:13:01, Serial0
>O IA    170.150.8.0/24 [110/193] via 170.150.43.4,
>00:13:01, Serial0
>O       170.150.4.0/26 [110/65] via 170.150.43.4,
>00:13:02, Serial0
>O       170.150.5.0/26 [110/129] via 170.150.43.4,
>00:13:02, Serial0
>C       170.150.6.0/26 is directly connected,
>Loopback20
>O IA    170.150.7.7/32 [110/194] via 170.150.43.4,
>00:13:02, Serial0
>O       170.150.3.3/32 [110/129] via 170.150.43.4,
>00:13:02, Serial0
>O IA    170.150.78.7/32 [110/193] via 170.150.43.4,
>00:13:02, Serial0
>O IA    170.150.78.8/32 [110/192] via 170.150.43.4,
>00:13:02, Serial0
>C       170.150.69.4/30 is directly connected, Serial1
>C       170.150.67.0/24 is directly connected,
>TokenRing0
>C    217.1.6.0/24 is directly connected, Loopback100
>R    199.1.8.0/24 [120/1] via 170.150.69.5, 00:02:30,
>Serial1
>R    199.1.2.0/24 [120/1] via 170.150.69.5, 00:02:30,
>Serial1
>      160.60.0.0/22 is subnetted, 1 subnets
>O E1    160.60.60.0 [110/214] via 170.150.43.4,
>00:13:02, Serial0
>R    199.1.0.0/24 [120/1] via 170.150.69.5, 00:02:30,
>Serial1
>R    199.1.6.0/24 [120/1] via 170.150.69.5, 00:02:30,
>Serial1
>R    199.1.4.0/24 [120/1] via 170.150.69.5, 00:02:31,
>Serial1
>R6#
>
>
>R4 config
>
>R4#sh run
>Building configuration...
>
>Current configuration:
>!
>version 12.1
>service timestamps debug uptime
>service timestamps log uptime
>no service password-encryption
>!
>hostname R4
>!
>no logging console
>!
>!
>!
>!
>!
>ip subnet-zero
>no ip domain-lookup
>!
>cns event-service server
>!
>!
>!
>!
>!
>interface Loopback10
>  ip address 170.150.47.4 255.255.255.0
>  ip ospf network point-to-point
>!
>interface Loopback20
>  ip address 170.150.4.2 255.255.255.192
>  ip ospf network point-to-point
>!
>interface Loopback100
>  ip address 217.1.4.1 255.255.255.0
>!
>interface Serial0
>  ip address 170.150.43.4 255.255.255.240
>  encapsulation frame-relay
>  ip ospf message-digest-key 1 md5 cisco
>  ip ospf network point-to-multipoint
>  ip ospf hello-interval 20
>  ip ospf priority 100
>  no fair-queue
>  frame-relay map ip 170.150.43.3 403 broadcast
>  frame-relay map ip 170.150.43.4 403 broadcast
>  frame-relay map ip 170.150.43.5 405 broadcast
>  frame-relay map ip 170.150.43.6 406 broadcast
>  no frame-relay inverse-arp
>  frame-relay lmi-type ansi
>!
>interface Serial1
>  ip address 170.150.144.2 255.255.255.252
>!
>interface TokenRing0
>  ip address 170.150.14.4 255.255.255.0
>  ring-speed 4
>!
>interface BRI0
>  no ip address
>  shutdown
>!
>interface Dialer0
>  ip address 170.150.45.6 255.255.255.252
>  no cdp enable
>!
>router ospf 10
>  area 0 authentication message-digest
>  area 0 range 170.150.4.0 255.255.255.192
>  area 0 range 170.150.43.0 255.255.255.0
>  area 0 range 170.150.45.4 255.255.255.252
>  area 4 range 170.150.14.0 255.255.255.0
>  area 4 range 170.150.47.0 255.255.255.0
>  network 170.150.4.0 0.0.0.63 area 0
>  network 170.150.14.0 0.0.0.255 area 4
>  network 170.150.43.0 0.0.0.15 area 0
>  network 170.150.45.4 0.0.0.3 area 0
>  network 170.150.47.0 0.0.0.255 area 4
>!
>ip classless
>no ip http server
>!
>!
>alias exec c conf t
>alias exec ir show ip route
>alias exec x show ipx route
>alias exec o show ip ospf
>alias exec e show ip eigrp
>alias exec b show ip bgp
>alias exec ib show ip int brief
>alias exec xb show ipx int brief
>alias exec xs show ipx servers
>alias exec d clear ip route *
>alias exec q clear ip bgp *
>alias exec crs copy run start
>!
>line con 0
>  transport input none
>line aux 0
>line vty 0 4
>  privilege level 15
>  login
>!
>end
>
>R4#sh ip ro
>Codes: C - connected, S - static, I - IGRP, 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, E - EGP
>        i - IS-IS, 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
>
>      170.150.0.0/16 is variably subnetted, 21 subnets,
>5 masks
>O IA    170.150.60.0/24 [110/65] via 170.150.43.6,
>00:36:29, Serial0
>O IA    170.150.58.4/30 [110/128] via 170.150.43.5,
>00:36:29, Serial0
>O       170.150.43.6/32 [110/64] via 170.150.43.6,
>00:36:29, Serial0
>O       170.150.43.5/32 [110/64] via 170.150.43.5,
>00:36:29, Serial0
>C       170.150.47.0/24 is directly connected,
>Loopback10
>O       170.150.43.3/32 [110/64] via 170.150.43.3,
>00:36:29, Serial0
>C       170.150.45.4/30 is directly connected, Dialer0
>C       170.150.43.0/28 is directly connected, Serial0
>O IA    170.150.33.0/24 [110/65] via 170.150.43.3,
>00:36:30, Serial0
>O IA    170.150.30.0/24 [110/74] via 170.150.43.3,
>00:36:30, Serial0
>C       170.150.14.0/24 is directly connected,
>TokenRing0
>O IA    170.150.8.0/24 [110/129] via 170.150.43.5,
>00:36:30, Serial0
>C       170.150.4.0/26 is directly connected,
>Loopback20
>O       170.150.5.0/26 [110/65] via 170.150.43.5,
>00:36:31, Serial0
>O       170.150.6.0/26 [110/65] via 170.150.43.6,
>00:36:31, Serial0
>O IA    170.150.7.7/32 [110/130] via 170.150.43.5,
>00:36:31, Serial0
>O       170.150.3.3/32 [110/65] via 170.150.43.3,
>00:36:31, Serial0
>O IA    170.150.78.7/32 [110/129] via 170.150.43.5,
>00:36:31, Serial0
>O IA    170.150.78.8/32 [110/128] via 170.150.43.5,
>00:36:31, Serial0
>O E1    170.150.69.4/30 [110/84] via 170.150.43.6,
>00:36:31, Serial0
>C       170.150.144.0/30 is directly connected,
>Serial1
>C    217.1.4.0/24 is directly connected, Loopback100
>O E1 199.1.8.0/24 [110/129] via 170.150.43.6,
>00:36:31, Serial0
>O E1 199.1.2.0/24 [110/129] via 170.150.43.6,
>00:36:31, Serial0
>      160.60.0.0/22 is subnetted, 1 subnets
>O E1    160.60.60.0 [110/150] via 170.150.43.5,
>00:36:31, Serial0
>O E1 199.1.0.0/24 [110/129] via 170.150.43.6,
>00:13:45, Serial0
>O E1 199.1.6.0/24 [110/129] via 170.150.43.6,
>00:36:32, Serial0
>O E1 199.1.4.0/24 [110/129] via 170.150.43.6,
>00:36:32, Serial0
>R4#
>
>
>
>Thanks in advance
>
>
>
>
>
>
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