Cheat sheet for bgp

http://packetlife.net/wiki/bgp/

Bgp route Aggregation

R1 configuration



router bgp 100
 no synchronization
 bgp log-neighbor-changes
 network 1.1.1.0 mask 255.255.255.0
 neighbor 131.1.12.2 remote-as 200
 no auto-summary


R1#sh ip bgp
BGP table version is 43, local router ID is 1.1.1.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
              r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete

   Network          Next Hop            Metric LocPrf Weight Path
*> 1.1.1.0/24       0.0.0.0                  0         32768 i
*> 2.2.0.0/22       131.1.12.2               0             0 200 i -------route aggregation is done for 2.2.x.x network


R5 configuration


interface Loopback2
 ip address 2.2.0.2 255.255.255.0
!
interface Loopback3
 ip address 2.2.1.2 255.255.255.0
!
interface Loopback4
 ip address 2.2.2.2 255.255.255.0
!
interface Loopback5
 ip address 2.2.3.2 255.255.255.0

router bgp 200
no synchronization
 bgp log-neighbor-changes
 network 2.2.0.0 mask 255.255.255.0
 network 2.2.1.0 mask 255.255.255.0
 network 2.2.2.0 mask 255.255.255.0
 network 2.2.3.0 mask 255.255.255.0
 aggregate-address 2.2.0.0 255.255.252.0 as-set summary-only
 neighbor 131.1.12.1 remote-as 100
 no auto-summary

BGP Dampening using Route-Map

Task 1
Configure R1 and R2 should apply the route dampening for prefixes 40.x.x.x according to the following:

• Max-Suppres=50 minutes
• Suppress=2000 points
• Reuse=800 points
• Half-Time=10 minutes

Prefixes 44.4.x.x should use the following dampening policy:

• Max-Suppres=90 minutes
• Suppress=2500 points
• Reuse=700 points
• Half-Time=20 minutes

R1 configuration



router bgp 123
 no synchronization
 bgp router-id 172.16.101.1
 bgp log-neighbor-changes
 bgp dampening route-map DAMPEN
 network 172.16.101.0 mask 255.255.255.0
 neighbor 10.1.13.3 remote-as 123
 neighbor 10.1.14.4 remote-as 40
 neighbor 10.1.14.4 next-hop-self
 no auto-summary


ip prefix-list NET_40 seq 5 permit 40.0.0.0/8 le 32
!
ip prefix-list NET_44 seq 5 permit 44.0.0.0/8 le 32
!
!
!
route-map DAMPEN permit 10
 match ip address prefix-list NET_40
 set dampening 15 800 3000 50
!
route-map DAMPEN permit 20
 match ip address prefix-list NET_44
 set dampening 15 800 3000 50

R1#sh ip bg dampening parameters
 dampening 15 800 3000 50 (route-map DAMPEN 10)
  Half-life time      : 15 mins       Decay Time       : 1280 secs
  Max suppress penalty:  8051         Max suppress time: 50 mins
  Suppress penalty    :  3000         Reuse penalty    : 800

 dampening 15 800 3000 50 (route-map DAMPEN 20)
  Half-life time      : 15 mins       Decay Time       : 1280 secs
  Max suppress penalty:  8051         Max suppress time: 50 mins
  Suppress penalty    :  3000         Reuse penalty    : 800

R1#







R2 configuration 

router bgp 123
 no synchronization
 bgp log-neighbor-changes
 bgp dampening route-map DAMPEN
 network 172.16.102.0 mask 255.255.255.0
 neighbor 10.1.23.3 remote-as 123
 neighbor 10.1.23.3 next-hop-self
 neighbor 10.1.24.4 remote-as 40
 no auto-summary

ip prefix-list NET_40 seq 5 permit 40.0.0.0/8 le 32
!
ip prefix-list NET_44 seq 5 permit 44.0.0.0/8 le 32
!
!
!
route-map DAMPEN permit 10
 match ip address prefix-list NET_40
 set dampening 15 800 3000 50
!
route-map DAMPEN permit 20
 match ip address prefix-list NET_44
 set dampening 20 700 2500 90

r2# sh ip bgp dampening parameters
 dampening 15 800 3000 50 (route-map DAMPEN 10)
  Half-life time      : 15 mins       Decay Time       : 1280 secs
  Max suppress penalty:  8051         Max suppress time: 50 mins
  Suppress penalty    :  3000         Reuse penalty    : 800

 dampening 20 700 2500 90 (route-map DAMPEN 20)
  Half-life time      : 20 mins       Decay Time       : 3190 secs
  Max suppress penalty: 15816         Max suppress time: 90 mins
  Suppress penalty    :  2500         Reuse penalty    : 700

Bgp route reflector

 

R1 configuration and output

router bgp 100
 no synchronization
 bgp log-neighbor-changes
 network 1.0.0.0
 neighbor 10.1.1.2 remote-as 100
 neighbor 10.1.1.2 route-reflector-client
 neighbor 10.1.1.3 remote-as 100
 neighbor 10.1.1.3 route-reflector-client
 no auto-summary

R1#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

C    1.0.0.0/8 is directly connected, Loopback0
B    2.0.0.0/8 [200/0] via 10.1.1.3, 00:05:39
B    3.0.0.0/8 [200/0] via 10.1.1.2, 00:05:38
C    10.0.0.0/8 is directly connected, FastEthernet0/0

R1#sh ip bgp
BGP table version is 14, local router ID is 10.1.1.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
              r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete

   Network          Next Hop            Metric LocPrf Weight Path
*> 1.0.0.0          0.0.0.0                  0         32768 i
*>i2.0.0.0          10.1.1.3                 0    100      0 i
*>i3.0.0.0          10.1.1.2                 0    100      0 i

R2 configuration and output

router bgp 100
 no synchronization
 bgp log-neighbor-changes
 network 2.0.0.0
 neighbor 10.1.1.1 remote-as 100
 no auto-summary

R2# 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

B    1.0.0.0/8 [200/0] via 10.1.1.1, 00:04:47
C    2.0.0.0/8 is directly connected, Loopback0
B    3.0.0.0/8 [200/0] via 10.1.1.2, 00:04:46
C    10.0.0.0/8 is directly connected, FastEthernet0/0
R2#sh ip bgp
BGP table version is 12, local router ID is 10.1.1.3
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
              r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete

   Network          Next Hop            Metric LocPrf Weight Path
*>i1.0.0.0          10.1.1.1                 0    100      0 i
*> 2.0.0.0          0.0.0.0                  0         32768 i
*>i3.0.0.0          10.1.1.2                 0    100      0 i
R2#

 R3 configuration and output

router bgp 100
 no synchronization
 bgp log-neighbor-changes
 network 3.0.0.0
 neighbor 10.1.1.1 remote-as 100
 no auto-summary

R3#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

B    1.0.0.0/8 [200/0] via 10.1.1.1, 00:05:24
B    2.0.0.0/8 [200/0] via 10.1.1.3, 00:05:24
C    3.0.0.0/8 is directly connected, Loopback0
C    10.0.0.0/8 is directly connected, FastEthernet0/0

 R3#sh ip bgp
BGP table version is 14, local router ID is 10.1.1.2
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
              r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete

   Network          Next Hop            Metric LocPrf Weight Path
*>i1.0.0.0          10.1.1.1                 0    100      0 i
*>i2.0.0.0          10.1.1.3                 0    100      0 i
*> 3.0.0.0          0.0.0.0                  0         32768 i

 R3#sh ip bgp summary
BGP router identifier 10.1.1.2, local AS number 100
BGP table version is 14, main routing table version 14
3 network entries using 360 bytes of memory
3 path entries using 156 bytes of memory
3/2 BGP path/bestpath attribute entries using 372 bytes of memory
1 BGP rrinfo entries using 24 bytes of memory
0 BGP route-map cache entries using 0 bytes of memory
0 BGP filter-list cache entries using 0 bytes of memory
Bitfield cache entries: current 1 (at peak 2) using 32 bytes of memory
BGP using 944 total bytes of memory
BGP activity 3/0 prefixes, 8/5 paths, scan interval 60 secs

Neighbor        V    AS MsgRcvd MsgSent   TblVer  InQ OutQ Up/Down  State/PfxRcd
10.1.1.1        4   100      33      27       14    0    0 00:05:31        2
R3#

Area authentication in ospf

Area authentication

To enable authentication for an OSPF area, use the area authentication command in router configuration mode. To remove an authentication specification of an area or a specified area from the configuration, use the no form of this command.

area area-id authentication [message-digest]

no area area-id authentication [message-digest]

area 0 authentication

!−−−  Plain text authentication is enabled for

!−−−  all interfaces in Area 0.

!---- Should be enable on all the Routers

Eg:-
Router ospf 10
log−adjacency−changes
network 70.0.0.0 0.255.255.255 area 0
network 192.16.64.0 0.0.0.255 area 0
area 0 authentication   Under Ospf process

A few learning notes on BGP command

neighbor 1.1.1.1 ttl-security hops 2
neighbor 1.1.1.1 disable-connected-check


By default  BGP will check that a eBGP peer is directly connected by comparing the peer address against directly connected interface addresses.  The BGP router will not even try to connect (no packets hit the wire) if the neighbor doesn't first pass the connected test.  Similarly the remote peer will not accept the peer connection if it does not pass the connected test.  This is beyond the IP TTL limitations related to eBGP, eBGP multihop and TTL security - the checking is at the application layer of BGP.

This check is disabled by :

    * neighbor disable-connected-check , or
    * neighbor ebgp-multihop <ttl> , when TTL > 1

The disable-connect-check  command is used when you want to establish peering of directly connect routers using the loopback interface (using the loopback as the BGP source is configured with neighbor update-source).


Eg:-          bgp log-neighbor-changes
             network 1.1.1.0 mask 255.255.255.0
             neighbor 2.2.2.2 remote-as 200
             neighbor 2.2.2.2 ttl-security hops 2
             neighbor 2.2.2.2 update-source Loopback0

Cisco New updates

https://learningnetwork.cisco.com/docs/DOC-4323

http://www.cisco.com/web/learning/le3/ccie/announcements/index.html#ccieexamprep201005

How to start CCIE journey

 Study Plan  http://ccietrek.wordpress.com/study-plan/

Cheat sheets for BGP.OSPF.RIP AND EIGRP

http://packetlife.net/library/cheat-sheets/

My Blog

http://learinghph3c.blogspot.com/

Frame-relay Monitoring and Troubleshooting

Frame Relay is a high-performance WAN protocol that operates at the physical and data link layers of the OSI reference model. Frame Relay originally was designed for use across Integrated Services Digital Network (ISDN) interfaces. Today, it is used over a variety of other network interfaces as well. This article focuses on Frame Relay's specifications and applications in the context of WAN services.

 http://docwiki.cisco.com/wiki/Frame_Relay

 Monitoring -- Frame Relay Troubleshooting Tasks

To troubleshoot and resolve Voice over Frame Relay configuration issues, perform the following tasks:

• If no calls are going through, ensure that the frame-relay voice bandwidth command is configured.
• If VoFR is configured on a PVC and there are problems with data connectivity on that PVC, ensure that the frame-relay fragment command has been configured.
• If data is not being transmitted but fragmentation is configured, ensure that Frame Relay traffic shaping is turned on.
• If the problem is with the dial plan or the dial peers, use the show dial-plan number command with the argument dial string to display which dial peers are being used when a specific number is called.
• If there are problems connecting an FRF.11 trunk call, ensure that the session protocol command in dial peer configuration is set to frf11-trunk.
• If FRF.11 trunk calls on the Cisco 2600 or Cisco 3600 series routers are being configured, verify that the called-number vofr command in dial peer configuration is configured and that its number matches the destination pattern of the corresponding POTS dial peer.
• Ensure that the voice port is set to no shutdown.
• Ensure that the serial port or the T1/E1 controller is set to no shutdown.
• Toggle the voice port by first entering shutdown and then no shutdown every time the connection trunk or no connection trunk command is entered.

Check the validity of the Voice over Frame Relay configuration by performing the following tasks:

• Enter the show frame-relay pvc command to show the status of the PVCs.
• Enter the show frame-relay vofr command with the arguments interface, dlci, cid to show statistics and information on the open subchannels.
• Enter the show frame-relay fragment command with the arguments interface number and dlci to show the Frame Relay fragmentation configuration.
• Enter the show traffic-shape queue command to display the traffic-shaping information if Frame Relay traffic shaping is configured. The queue option displays the queueing statistics. For more information about traffic shaping,

STP.RSTP and PSTP

STP(Spanning-tree Protocol): Layer 2 protocol used in LAN enviroment to

avoid:

Broadcast Storms
Mac-Table Inestability
Multiples copies of frames.

And it is defined in 802.1d Standard.

RSTP(Rapid Spanning Tree Protocol-802.1w Standard): it is the enhanced protocol of STP,

the main caracteristic of this one is Faster than STP (it converge in less than 6 seconds).

PVST+ (Per Vlan Spanning Tree Plus) : This feature (by cisco) is used to create an instace of

STP for each VLAN. e.g.

If you have a switch with 3 vlans you will have a 3 instances of VLANs that you could
modify the parameters (like to make root bridge for a specific VLAN) independiently
accord to your design goals.

MIST(Multiple Instances of Spaning Tree-802.1s): This protocol is the equivalent for PVST, however

this protocol just can be used in conjunction with RSTP.

Hope this will be useful


Some useful Link   :-

http://en.wikipedia.org/wiki/Rapid_Spanning_Tree_Protocol#Rapid_Spanning_Tree_Protocol_.28RSTP.29

Frame-relay with point to point interfaces

Frame-relay configuration

Frame-relay with point to point interfaces (ospf)

-------------------------------------------------------------



Frame-relay router Output

Frame-relay-switch#sh frame-relay pvc | in 202
DLCI = 202, DLCI USAGE = SWITCHED, PVC STATUS = ACTIVE, INTERFACE = Serial1/0



Frame-relay-switch#sh frame-relay pvc | in 501
DLCI = 501, DLCI USAGE = SWITCHED, PVC STATUS = ACTIVE, INTERFACE = Serial1/1
Frame-relay-switch#




R3 configuration and output

interface Serial1/0
 ip address 192.168.1.9 255.255.255.252
 encapsulation frame-relay
 ip ospf network point-to-point
 no fair-queue
 serial restart-delay 0
 frame-relay map ip 192.168.1.10 202 broadcast
 no frame-relay inverse-arp
.


R3#sh ip ospf neighbor

Neighbor ID     Pri   State           Dead Time   Address         Interface
4.4.4.4           0   FULL/  -        00:00:36    192.168.1.10    Serial1/0


R3#sh frame-relay map
Serial1/0 (up): ip 192.168.1.10 dlci 202(0xCA,0x30A0), static,
              broadcast,
              CISCO, status defined, active
R3#

R3#sh frame-relay pvc

PVC Statistics for interface Serial1/0 (Frame Relay DTE)

              Active     Inactive      Deleted       Static
  Local          1            0            0            0
  Switched       0            0            0            0
  Unused         0            2            0            0

DLCI = 201, DLCI USAGE = UNUSED, PVC STATUS = INACTIVE, INTERFACE = Serial1/0

  input pkts 0             output pkts 0            in bytes 0
  out bytes 0              dropped pkts 0           in pkts dropped 0
  out pkts dropped 0                out bytes dropped 0
  in FECN pkts 0           in BECN pkts 0           out FECN pkts 0
  out BECN pkts 0          in DE pkts 0             out DE pkts 0
  out bcast pkts 0         out bcast bytes 0
  5 minute input rate 0 bits/sec, 0 packets/sec
  5 minute output rate 0 bits/sec, 0 packets/sec
  pvc create time 00:11:46, last time pvc status changed 00:11:46

DLCI = 202, DLCI USAGE = LOCAL, PVC STATUS = ACTIVE, INTERFACE = Serial1/0

  input pkts 77            output pkts 63           in bytes 6604
  out bytes 5468           dropped pkts 0           in pkts dropped 0
  out pkts dropped 0                out bytes dropped 0
  in FECN pkts 0           in BECN pkts 0           out FECN pkts 0
  out BECN pkts 0          in DE pkts 0             out DE pkts 0
  out bcast pkts 53        out bcast bytes 4428
  5 minute input rate 0 bits/sec, 0 packets/sec
  5 minute output rate 0 bits/sec, 0 packets/sec
  pvc create time 00:11:46, last time pvc status changed 00:11:36

DLCI = 203, DLCI USAGE = UNUSED, PVC STATUS = INACTIVE, INTERFACE = Serial1/0

  input pkts 0             output pkts 0            in bytes 0
  out bytes 0              dropped pkts 0           in pkts dropped 0
  out pkts dropped 0                out bytes dropped 0
  in FECN pkts 0           in BECN pkts 0           out FECN pkts 0
  out BECN pkts 0          in DE pkts 0             out DE pkts 0
  out bcast pkts 0         out bcast bytes 0
  5 minute input rate 0 bits/sec, 0 packets/sec
  5 minute output rate 0 bits/sec, 0 packets/sec
  pvc create time 00:11:46, last time pvc status changed 00:11:46
R3#

R4 configuration and output

interface Serial1/1
 ip address 192.168.1.10 255.255.255.252
 encapsulation frame-relay
 ip ospf network point-to-point
 serial restart-delay 0
 frame-relay map ip 192.168.1.9 501 broadcast
 no frame-relay inverse-arp
!



R4#sh ip ospf neighbor

Neighbor ID     Pri   State           Dead Time   Address         Interface
3.3.3.3           0   FULL/  -        00:00:32    192.168.1.9     Serial1/1
R4#

R4#sh frame-relay map
Serial1/1 (up): ip 192.168.1.9 dlci 501(0x1F5,0x7C50), static,
              broadcast,
              CISCO, status defined, active
R4#sh frame-relay pvc interface serial 1/1

PVC Statistics for interface Serial1/1 (Frame Relay DTE)

              Active     Inactive      Deleted       Static
  Local          1            0            0            0
  Switched       0            0            0            0
  Unused         0            2            0            0

DLCI = 501, DLCI USAGE = LOCAL, PVC STATUS = ACTIVE, INTERFACE = Serial1/1

  input pkts 59            output pkts 72           in bytes 5132
  out bytes 6184           dropped pkts 0           in pkts dropped 0
  out pkts dropped 0                out bytes dropped 0
  in FECN pkts 0           in BECN pkts 0           out FECN pkts 0
  out BECN pkts 0          in DE pkts 0             out DE pkts 0
  out bcast pkts 62        out bcast bytes 5144
  5 minute input rate 0 bits/sec, 0 packets/sec
  5 minute output rate 0 bits/sec, 0 packets/sec
  pvc create time 00:12:59, last time pvc status changed 00:10:49

DLCI = 502, DLCI USAGE = UNUSED, PVC STATUS = INACTIVE, INTERFACE = Serial1/1

  input pkts 0             output pkts 0            in bytes 0
  out bytes 0              dropped pkts 0           in pkts dropped 0
  out pkts dropped 0                out bytes dropped 0
  in FECN pkts 0           in BECN pkts 0           out FECN pkts 0
  out BECN pkts 0          in DE pkts 0             out DE pkts 0
  out bcast pkts 0         out bcast bytes 0
  5 minute input rate 0 bits/sec, 0 packets/sec
  5 minute output rate 0 bits/sec, 0 packets/sec
  pvc create time 00:13:03, last time pvc status changed 00:13:03

DLCI = 503, DLCI USAGE = UNUSED, PVC STATUS = INACTIVE, INTERFACE = Serial1/1

  input pkts 0             output pkts 0            in bytes 0
  out bytes 0              dropped pkts 0           in pkts dropped 0
  out pkts dropped 0                out bytes dropped 0
  in FECN pkts 0           in BECN pkts 0           out FECN pkts 0
  out BECN pkts 0          in DE pkts 0             out DE pkts 0
  out bcast pkts 0         out bcast bytes 0
  5 minute input rate 0 bits/sec, 0 packets/sec
  5 minute output rate 0 bits/sec, 0 packets/sec
  pvc create time 00:13:04, last time pvc status changed 00:13:04
R4#

Frame-relay configuration with non-broadcast network

R3 configuration and output

R3#sh run int serial 1/0
Building configuration...

Current configuration : 264 bytes
!
interface Serial1/0
 ip address 192.168.1.9 255.255.255.0
 encapsulation frame-relay
 ip ospf network non-broadcast
 no fair-queue
 serial restart-delay 0
 frame-relay map ip 192.168.1.11 203
 frame-relay map ip 192.168.1.10 202
 no frame-relay inverse-arp
end

interface Loopback0
 ip address 3.3.3.3 255.255.255.255
end


router ospf 1
 router-id 3.3.3.3
 log-adjacency-changes
 network 0.0.0.0 255.255.255.255 area 0
 neighbor 192.168.1.10
 neighbor 192.168.1.11
!


R3#
R3#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

     3.0.0.0/32 is subnetted, 1 subnets
C       3.3.3.3 is directly connected, Loopback0
     4.0.0.0/32 is subnetted, 1 subnets
O       4.4.4.4 [110/65] via 192.168.1.10, 00:20:35, Serial1/0
     7.0.0.0/32 is subnetted, 1 subnets
O       7.7.7.7 [110/65] via 192.168.1.11, 00:20:35, Serial1/0
C    192.168.1.0/24 is directly connected, Serial1/0
R3#

R3#sh ip ospf neighbor

Neighbor ID     Pri   State           Dead Time   Address         Interface
4.4.4.4           0   FULL/DROTHER    00:01:58    192.168.1.10    Serial1/0
7.7.7.7           0   FULL/DROTHER    00:01:32    192.168.1.11    Serial1/0
R3#

R4 configuration and output

R4#sh running-config interface serial 1/1
Building configuration...

Current configuration : 269 bytes
!
interface Loopback0
 ip address 4.4.4.4 255.255.255.255

interface Serial1/1
 ip address 192.168.1.10 255.255.255.0
 encapsulation frame-relay
 ip ospf network non-broadcast
 ip ospf priority 0
 serial restart-delay 0
 frame-relay map ip 192.168.1.11 501
 frame-relay map ip 192.168.1.9 501
 no frame-relay inverse-arp
end

R4#

R4#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

     3.0.0.0/32 is subnetted, 1 subnets
O       3.3.3.3 [110/65] via 192.168.1.9, 00:22:16, Serial1/1
     4.0.0.0/32 is subnetted, 1 subnets
C       4.4.4.4 is directly connected, Loopback0
     7.0.0.0/32 is subnetted, 1 subnets
O       7.7.7.7 [110/65] via 192.168.1.11, 00:22:06, Serial1/1
C    192.168.1.0/24 is directly connected, Serial1/1
R4#

R4#sh ip ospf neighbor

Neighbor ID     Pri   State           Dead Time   Address         Interface
3.3.3.3           1   FULL/DR         00:01:35    192.168.1.9     Serial1/1
R4#

R7 configuration and output

interface Serial1/2
 ip address 192.168.1.11 255.255.255.0
 encapsulation frame-relay
 ip ospf network non-broadcast
 ip ospf priority 0
 serial restart-delay 0
 frame-relay map ip 192.168.1.10 301
 frame-relay map ip 192.168.1.9 301
 no frame-relay inverse-arp
end

R7#sh running-config interface loopback 0
Building configuration...

Current configuration : 63 bytes
!
interface Loopback0
 ip address 7.7.7.7 255.255.255.255
end

R7#
R7#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

     3.0.0.0/32 is subnetted, 1 subnets
O       3.3.3.3 [110/65] via 192.168.1.9, 00:24:08, Serial1/2
     4.0.0.0/32 is subnetted, 1 subnets
O       4.4.4.4 [110/65] via 192.168.1.10, 00:23:58, Serial1/2
     7.0.0.0/32 is subnetted, 1 subnets
C       7.7.7.7 is directly connected, Loopback0
C    192.168.1.0/24 is directly connected, Serial1/2
R7#

R7#sh ip ospf neighbor

Neighbor ID     Pri   State           Dead Time   Address         Interface
3.3.3.3           1   FULL/DR         00:01:37    192.168.1.9     Serial1/2
R7#

Border Gateway Protocol (BGP) Multi-homing: Design and Troubleshooting Video

https://supportforums.cisco.com/videos/1787