Summarization with Leak-Map – EIGRP

Summarization with Leak-Map  – EIGRP



Summarization is used to summarize small subnets to
bigger subnet in order to reduce the routing table. Once the summarization is
done all the child subnets are suppressed and only summarize route is advertise
to the neighbor.

Summarization is done under interface prompt and will be
applicable to neighbor attached on the interface. If you want to advertise some
specific route along with summarized route then use LEAK_MAP.

In below example, R2 is doing summarization for all
10.1.1.x subnets. But we want to advertise 10.1.1.16/28 along with summarized
route i.e. 10.1.1.0/24

R1:-

interface Loopback0
 ip address 1.1.1.1
255.255.255.255

interface FastEthernet2/0
description “connected to R2”
 ip address
12.12.12.1 255.255.255.0
no shut

router eigrp 1
 network 1.1.1.1
0.0.0.0
 network 12.12.12.1
0.0.0.0
 eigrp router-id
1.1.1.1
no auto-summ


R2:-

interface Loopback0
 ip address 2.2.2.2
255.255.255.255

interface FastEthernet0/0
description “connected to R3”
 ip address
23.23.23.2 255.255.255.0
no shut

interface FastEthernet1/0
description “connected to R5”
 ip address
25.25.25.2 255.255.255.0
no shut

interface FastEthernet2/0
description “connected to R5”
 ip address
12.12.12.2 255.255.255.0
 ip summary-address
eigrp 1 10.1.1.0 255.255.255.0 leak-map Allow_10.1.1.16/28
no shut

route-map Allow_10.1.1.16/28 permit 10
 match ip address
prefix-list Route_10.1.1.16/28

ip prefix-list Route_10.1.1.16/28 seq 5 permit 10.1.1.16/28  –<<Advertising
specific 10.1.1.16/28  route with Summary
route

interface FastEthernet3/0
description “connected to LAN”
 ip address
10.1.1.1 255.255.255.240
no shut

interface FastEthernet1/1
description “connected to R4”
 ip address
24.24.24.2 255.255.255.0
no shut


router eigrp 1
 network 2.2.2.2
0.0.0.0
 network 10.1.1.1
0.0.0.0
 network 12.12.12.2
0.0.0.0
 network 23.23.23.2
0.0.0.0
 network 25.25.25.2
0.0.0.0
network 24.24.24.2 0.0.0.0
 eigrp router-id
2.2.2.2


R3:-


interface Loopback0
 ip address 3.3.3.3
255.255.255.255

interface FastEthernet0/0
 description
“connected to R2”
 ip address
23.23.23.3 255.255.255.0
no shut

interface FastEthernet3/0
description “connected to LAN”
 ip address
10.1.1.17 255.255.255.240
no shut

router eigrp 1
 network 3.3.3.3
0.0.0.0
 network 10.1.1.17
0.0.0.0
 network 23.23.23.3
0.0.0.0
 eigrp router-id
3.3.3.3

R4:-

interface Loopback0
 ip address 4.4.4.4
255.255.255.0

interface FastEthernet1/1
description “connected to R2”
 ip address
24.24.24.4 255.255.255.0
no shut

interface FastEthernet3/0
description “connected to LAN”

 ip address
10.1.1.49 255.255.255.240
no shut

router eigrp 1
 network 4.4.4.4
0.0.0.0
 network 10.1.1.49
0.0.0.0
 network 24.24.24.4
0.0.0.0



R5:-

interface Loopback0
 ip address 5.5.5.5
255.255.255.255

interface FastEthernet1/0
description “connected to R2”
 ip address
25.25.25.5 255.255.255.0
no shut

interface FastEthernet3/0
description “connected to LAN”
 ip address
10.1.1.33 255.255.255.240
no shut

router eigrp 1
 network 5.5.5.5
0.0.0.0
 network 10.1.1.33
0.0.0.0
 network 25.25.25.5
0.0.0.0
 eigrp router-id
5.5.5.5


Verification:-

R1:-

R1#sh ip eigrp neighbors
EIGRP-IPv4 Neighbors for AS(1)
H   Address                 Interface       Hold Uptime   SRTT  
RTO  Q  Seq
                                           
(sec)         (ms)      
Cnt Num
0   12.12.12.2              Fa2/0             11 01:26:51  246  1476  0  27


R1#sh ip route
Codes: L – local, 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, H – NHRP
       + –
replicated route, % – next hop override

Gateway of last resort is not set

      1.0.0.0/32 is
subnetted, 1 subnets
C        1.1.1.1 is
directly connected, Loopback0
      2.0.0.0/32 is
subnetted, 1 subnets
D        2.2.2.2
[90/156160] via 12.12.12.2, 00:00:04, FastEthernet2/0
      3.0.0.0/32 is
subnetted, 1 subnets
D        3.3.3.3
[90/158720] via 12.12.12.2, 00:00:04, FastEthernet2/0
      4.0.0.0/24 is
subnetted, 1 subnets
D        4.4.4.0
[90/158720] via 12.12.12.2, 00:00:04, FastEthernet2/0
      10.0.0.0/8 is
variably subnetted, 2 subnets, 2 masks
D       
10.1.1.0/24 [90/30720] via 12.12.12.2, 00:00:04, FastEthernet2/0  –<< Summary
Route
D       
10.1.1.16/28 [90/33280] via 12.12.12.2, 00:00:04, FastEthernet2/0 –<< Specific Route
      12.0.0.0/8 is
variably subnetted, 2 subnets, 2 masks
C       
12.12.12.0/24 is directly connected, FastEthernet2/0
L       
12.12.12.1/32 is directly connected, FastEthernet2/0
      23.0.0.0/24
is subnetted, 1 subnets
D        23.23.23.0
[90/30720] via 12.12.12.2, 00:00:04, FastEthernet2/0
      24.0.0.0/24
is subnetted, 1 subnets
D        24.24.24.0
[90/30720] via 12.12.12.2, 00:00:04, FastEthernet2/0
      25.0.0.0/24
is subnetted, 1 subnets
D        25.25.25.0
[90/30720] via 12.12.12.2, 00:00:04, FastEthernet2/0

R2:-


R2#sh ip eigrp neighbors
EIGRP-IPv4 Neighbors for AS(2)
H   Address                 Interface       Hold Uptime   SRTT  
RTO  Q  Seq
                                           
(sec)         (ms)       Cnt Num
0   23.23.23.3              Fa0/0             14 01:53:38 1402  5000 
0  4
EIGRP-IPv4 Neighbors for AS(1)
H   Address                 Interface       Hold Uptime   SRTT  
RTO  Q  Seq
                                           
(sec)         (ms)       Cnt Num
3   24.24.24.4              Fa1/1             12 00:04:18   24  
200  0  5
2   25.25.25.5              Fa1/0             12 01:48:39   35  
210  0  9
1   23.23.23.3              Fa0/0             13 01:49:32   45  
270  0  9
0   12.12.12.1              Fa2/0             11 01:50:21   48  
432  0  15
R2#sh ip rou
R2#sh ip route
Codes: L – local, 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, H – NHRP
       + –
replicated route, % – next hop override

Gateway of last resort is not set

      1.0.0.0/32 is
subnetted, 1 subnets
D        1.1.1.1
[90/156160] via 12.12.12.1, 01:50:21, FastEthernet2/0
      2.0.0.0/32 is
subnetted, 1 subnets
C        2.2.2.2 is
directly connected, Loopback0
      3.0.0.0/32 is
subnetted, 1 subnets
D        3.3.3.3
[90/156160] via 23.23.23.3, 01:49:34, FastEthernet0/0
      4.0.0.0/24 is
subnetted, 1 subnets
D        4.4.4.0
[90/156160] via 24.24.24.4, 00:04:18, FastEthernet1/1
      5.0.0.0/32 is
subnetted, 1 subnets
B        5.5.5.5
[20/0] via 25.25.25.5, 01:52:21
      10.0.0.0/8 is variably subnetted, 6 subnets,
3 masks
D       
10.1.1.0/24 is a summary, 00:04:18, Null0
C       
10.1.1.0/28 is directly connected, FastEthernet3/0
L       
10.1.1.1/32 is directly connected, FastEthernet3/0
D       
10.1.1.16/28 [90/30720] via 23.23.23.3, 01:45:11, FastEthernet0/0
D       
10.1.1.32/28 [90/30720] via 25.25.25.5, 01:44:33, FastEthernet1/0
D       
10.1.1.48/28 [90/30720] via 24.24.24.4, 00:02:21, FastEthernet1/1
      12.0.0.0/8 is
variably subnetted, 2 subnets, 2 masks
C       
12.12.12.0/24 is directly connected, FastEthernet2/0
L       
12.12.12.2/32 is directly connected, FastEthernet2/0
      23.0.0.0/8 is
variably subnetted, 2 subnets, 2 masks
C       
23.23.23.0/24 is directly connected, FastEthernet0/0
L        23.23.23.2/32 is directly connected,
FastEthernet0/0
      24.0.0.0/8 is
variably subnetted, 2 subnets, 2 masks
C       
24.24.24.0/24 is directly connected, FastEthernet1/1
L       
24.24.24.2/32 is directly connected, FastEthernet1/1
      25.0.0.0/8 is
variably subnetted, 2 subnets, 2 masks
C       
25.25.25.0/24 is directly connected, FastEthernet1/0
L       
25.25.25.2/32 is directly connected, FastEthernet1/0
      34.0.0.0/24
is subnetted, 1 subnets
D        34.34.34.0
[90/30720] via 23.23.23.3, 01:53:38, FastEthernet0/0
R2#

R3:-

R3#sh ip eigrp neighbors
EIGRP-IPv4 Neighbors for AS(1)
H   Address                 Interface       Hold Uptime   SRTT  
RTO  Q  Seq
                                           
(sec)         (ms)       Cnt Num
0   23.23.23.2              Fa0/0             13 01:50:25   68  
408  0  41
R3#sh ip rou
R3#sh ip route
Codes: L – local, 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, H – NHRP
       + –
replicated route, % – next hop override

Gateway of last resort is not set

      1.0.0.0/32 is
subnetted, 1 subnets
D        1.1.1.1
[90/158720] via 23.23.23.2, 00:00:21, FastEthernet0/0
      2.0.0.0/32 is
subnetted, 1 subnets
D        2.2.2.2
[90/156160] via 23.23.23.2, 00:00:21, FastEthernet0/0
      3.0.0.0/32 is
subnetted, 1 subnets
C        3.3.3.3 is
directly connected, Loopback0
      4.0.0.0/24 is
subnetted, 1 subnets
D        4.4.4.0
[90/158720] via 23.23.23.2, 00:00:21, FastEthernet0/0
      5.0.0.0/32 is
subnetted, 1 subnets
B        5.5.5.5
[200/0] via 23.23.23.2, 00:00:21
      10.0.0.0/8 is
variably subnetted, 5 subnets, 2 masks
D        10.1.1.0/28
[90/30720] via 23.23.23.2, 00:00:21, FastEthernet0/0
C       
10.1.1.16/28 is directly connected, FastEthernet3/0
L       
10.1.1.17/32 is directly connected, FastEthernet3/0
D       
10.1.1.32/28 [90/33280] via 23.23.23.2, 00:00:21, FastEthernet0/0
D       
10.1.1.48/28 [90/33280] via 23.23.23.2, 00:00:21, FastEthernet0/0
      12.0.0.0/8 is
variably subnetted, 2 subnets, 2 masks
C       
12.12.12.0/24 is directly connected, FastEthernet2/0
L       
12.12.12.2/32 is directly connected, FastEthernet2/0
      23.0.0.0/8 is
variably subnetted, 2 subnets, 2 masks
C       
23.23.23.0/24 is directly connected, FastEthernet0/0
L       
23.23.23.3/32 is directly connected, FastEthernet0/0
      24.0.0.0/24
is subnetted, 1 subnets
D        24.24.24.0
[90/30720] via 23.23.23.2, 00:00:21, FastEthernet0/0
      25.0.0.0/8 is
variably subnetted, 2 subnets, 2 masks
C       
25.25.25.0/24 is directly connected, FastEthernet1/0
L       
25.25.25.2/32 is directly connected, FastEthernet1/0
      34.0.0.0/8 is
variably subnetted, 2 subnets, 2 masks
C       
34.34.34.0/24 is directly connected, FastEthernet0/1
L       
34.34.34.3/32 is directly connected, FastEthernet0/1

R4:-

R4#     sh ip eigrp
neighbors
EIGRP-IPv4 Neighbors for AS(1)
H   Address                 Interface       Hold Uptime   SRTT  
RTO  Q  Seq
                                           
(sec)         (ms)       Cnt Num
0   24.24.24.2              Fa1/1             12 00:06:04   43  
258  0  38

R4#sh ip route
Codes: L – local, 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, H – NHRP
       + –
replicated route, % – next hop override

Gateway of last resort is not set

      1.0.0.0/32 is
subnetted, 1 subnets
D        1.1.1.1
[90/158720] via 24.24.24.2, 00:06:03, FastEthernet1/1
      2.0.0.0/32 is
subnetted, 1 subnets
D        2.2.2.2
[90/156160] via 24.24.24.2, 00:06:03, FastEthernet1/1
      3.0.0.0/32 is
subnetted, 1 subnets
D        3.3.3.3
[90/158720] via 24.24.24.2, 00:06:03, FastEthernet1/1
      4.0.0.0/8 is
variably subnetted, 2 subnets, 2 masks
C        4.4.4.0/24
is directly connected, Loopback0
L        4.4.4.4/32
is directly connected, Loopback0
      10.0.0.0/8 is
variably subnetted, 5 subnets, 2 masks
D       
10.1.1.0/28 [90/30720] via 24.24.24.2, 00:06:03, FastEthernet1/1
D       
10.1.1.16/28 [90/33280] via 24.24.24.2, 00:06:03, FastEthernet1/1
D       
10.1.1.32/28 [90/33280] via 24.24.24.2, 00:06:03, FastEthernet1/1
C       
10.1.1.48/28 is directly connected, FastEthernet3/0
L       
10.1.1.49/32 is directly connected, FastEthernet3/0
      12.0.0.0/24
is subnetted, 1 subnets
D        12.12.12.0
[90/30720] via 24.24.24.2, 00:06:03, FastEthernet1/1
      23.0.0.0/24
is subnetted, 1 subnets
D        23.23.23.0
[90/30720] via 24.24.24.2, 00:06:03, FastEthernet1/1
      24.0.0.0/8 is
variably subnetted, 2 subnets, 2 masks
C       
24.24.24.0/24 is directly connected, FastEthernet1/1
L       
24.24.24.4/32 is directly connected, FastEthernet1/1
      25.0.0.0/24
is subnetted, 1 subnets
D        25.25.25.0
[90/30720] via 24.24.24.2, 00:06:03, FastEthernet1/1

R5:-

R5#sh ip eigrp neighbors
EIGRP-IPv4 Neighbors for AS(1)
H   Address                 Interface       Hold Uptime   SRTT  
RTO  Q  Seq
                                           
(sec)         (ms)       Cnt Num
0   25.25.25.2              Fa1/0             13 01:49:52   54  
324  0  40
R5#sh ip rou
R5#sh ip route
Codes: L – local, 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, H – NHRP
       + –
replicated route, % – next hop override

Gateway of last resort is not set

      1.0.0.0/32 is
subnetted, 1 subnets
D        1.1.1.1
[90/158720] via 25.25.25.2, 01:49:54, FastEthernet1/0
      2.0.0.0/32 is
subnetted, 1 subnets
B        2.2.2.2
[20/0] via 25.25.25.2, 01:53:34
      3.0.0.0/32 is
subnetted, 1 subnets
B        3.3.3.3
[20/0] via 25.25.25.2, 01:53:34
      4.0.0.0/24 is
subnetted, 1 subnets
D        4.4.4.0
[90/158720] via 25.25.25.2, 00:05:31, FastEthernet1/0
      5.0.0.0/32 is
subnetted, 1 subnets
C        5.5.5.5 is
directly connected, Loopback0
      10.0.0.0/8 is
variably subnetted, 5 subnets, 2 masks
D       
10.1.1.0/28 [90/30720] via 25.25.25.2, 01:49:00, FastEthernet1/0
D       
10.1.1.16/28 [90/33280] via 25.25.25.2, 01:46:24, FastEthernet1/0
C       
10.1.1.32/28 is directly connected, FastEthernet3/0
L       
10.1.1.33/32 is directly connected, FastEthernet3/0
D       
10.1.1.48/28 [90/33280] via 25.25.25.2, 00:03:34, FastEthernet1/0
      12.0.0.0/24
is subnetted, 1 subnets
D        12.12.12.0
[90/30720] via 25.25.25.2, 01:49:54, FastEthernet1/0
      23.0.0.0/24
is subnetted, 1 subnets
D        23.23.23.0
[90/30720] via 25.25.25.2, 01:49:54, FastEthernet1/0
      24.0.0.0/24
is subnetted, 1 subnets
D        24.24.24.0
[90/30720] via 25.25.25.2, 00:05:33, FastEthernet1/0
      25.0.0.0/8 is
variably subnetted, 2 subnets, 2 masks
C       
25.25.25.0/24 is directly connected, FastEthernet1/0
L       
25.25.25.5/32 is directly connected, FastEthernet1/0


R5#