Here's the initial configs - the topology is R1-R2-R3. Where R1 is not performing any dynamic routing (R2 is it's default gateway) and R2 has an EIGRP adjacency with R3.
R1
hostname R1interface Loopback0
ip address 10.1.1.0 255.255.255.255
!
interface Loopback1
ip address 10.1.1.1 255.255.255.255
!
interface Loopback2
ip address 10.1.1.2 255.255.255.255
!
interface Loopback3
ip address 10.1.1.3 255.255.255.255
!
interface Serial0/0
ip address 10.1.12.1 255.255.255.0
encapsulation frame-relay
frame-relay map ip 10.1.12.2 102 broadcast
no frame-relay inverse-arp
!
ip route 0.0.0.0 0.0.0.0 10.1.12.2
R2
hostname R2
interface Serial0/0
no ip address
encapsulation frame-relay
no frame-relay inverse-arp
!
interface Serial0/0.21 point-to-point
ip address 10.1.12.2 255.255.255.0
snmp trap link-status
frame-relay interface-dlci 201
!
interface Serial0/0.23 point-to-point
ip address 10.1.23.2 255.255.255.0
snmp trap link-status
frame-relay interface-dlci 203
!
router eigrp 23
redistribute static metric 1 1 1 1 1
network 10.1.23.2 0.0.0.0
no auto-summary
!
ip route 10.1.1.0 255.255.255.255 10.1.12.1
ip route 10.1.1.1 255.255.255.255 10.1.12.1
ip route 10.1.1.2 255.255.255.255 10.1.12.1
ip route 10.1.1.3 255.255.255.255 10.1.12.1
R3
hostname R3
interface Serial0/0
ip address 10.1.23.3 255.255.255.0
encapsulation frame-relay
frame-relay map ip 10.1.23.2 302 broadcast
no frame-relay inverse-arp
!
router eigrp 23
network 10.1.23.3 0.0.0.0
no auto-summary
!
Ok, so nothing special so far, lets have look at what's in the EIGRP topology table:
R2#sh ip eigrp topology
IP-EIGRP Topology Table for AS(23)/ID(10.1.23.2)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - reply Status, s - sia Status
P 10.1.1.2/32, 1 successors, FD is 2560000256
via Rstatic (2560000256/0)
P 10.1.1.3/32, 1 successors, FD is 2560000256
via Rstatic (2560000256/0)
P 10.1.1.0/32, 1 successors, FD is 2560000256
via Rstatic (2560000256/0)
P 10.1.1.1/32, 1 successors, FD is 2560000256
via Rstatic (2560000256/0)
P 10.1.23.0/24, 1 successors, FD is 2169856
via Connected, Serial0/0.23
R2#sh ip eigrp topology 10.1.1.0/32
IP-EIGRP (AS 23): Topology entry for 10.1.1.0/32
State is Passive, Query origin flag is 1, 1 Successor(s), FD is 2560000256
Routing Descriptor Blocks:
10.1.12.1, from Rstatic, Send flag is 0x0
Composite metric is (2560000256/0), Route is External
Vector metric:
Minimum bandwidth is 1 Kbit
Total delay is 10 microseconds
Reliability is 1/255
Load is 1/255
Minimum MTU is 1
Hop count is 0
External data:
Originating router is 10.1.23.2 (this system)
AS number of route is 0
External protocol is Static, external metric is 0
Administrator tag is 0 (0x00000000)
This is all normal, static routes redistributed to into EIGRP are external routes...
R3#sh ip route | b Gateway
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 5 subnets, 2 masks
D EX 10.1.1.2/32 [170/2560512256] via 10.1.23.2, 00:03:05, Serial0/0
D EX 10.1.1.3/32 [170/2560512256] via 10.1.23.2, 00:03:05, Serial0/0
D EX 10.1.1.0/32 [170/2560512256] via 10.1.23.2, 00:03:05, Serial0/0
D EX 10.1.1.1/32 [170/2560512256] via 10.1.23.2, 00:03:05, Serial0/0
C 10.1.23.0/24 is directly connected, Serial0/0
So as I mentioned earlier we can actually make these static routes appear as internal to EIGRP but to make it happen we need to follow a few rules to make it work:
1) The static routes must use an interface as the next-hop rather than an using the next-hop IP Address:
R2#conf t
Enter configuration commands, one per line. End with CNTL/Z.
R2(config)#no ip route 10.1.1.0 255.255.255.255 10.1.12.1
R2(config)#ip route 10.1.1.0 255.255.255.255 s0/0.21
R2(config)#no ip route 10.1.1.1 255.255.255.255 10.1.12.1
R2(config)#ip route 10.1.1.1 255.255.255.255 s0/0.21
R2(config)#no ip route 10.1.1.2 255.255.255.255 10.1.12.1
R2(config)#ip route 10.1.1.2 255.255.255.255 s0/0.21
R2(config)#no ip route 10.1.1.3 255.255.255.255 10.1.12.1
R2(config)#ip route 10.1.1.3 255.255.255.255 s0/0.21
Update: 31 March 2012 - Tom Kacprzynski rightly informed me that step 2 is not actually required at all for this procedure to work. Thanks Tom!
3) Include the networks of the static routes into EIGRP
R2(config-router)#network 10.1.1.0 0.0.0.3
R2(config-router)#end
Now to see what has changed:
R2#show ip route | b Gateway
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
C 10.1.12.0/24 is directly connected, Serial0/0.21
S 10.1.1.2/32 is directly connected, Serial0/0.21
S 10.1.1.3/32 is directly connected, Serial0/0.21
S 10.1.1.0/32 is directly connected, Serial0/0.21
S 10.1.1.1/32 is directly connected, Serial0/0.21
C 10.1.23.0/24 is directly connected, Serial0/0.23
These are still definitely static routes, what about the EIGRP topology?
R2#sh ip eigrp topology 10.1.1.0/32
IP-EIGRP (AS 23): Topology entry for 10.1.1.0/32
State is Passive, Query origin flag is 1, 1 Successor(s), FD is 2560000256
Routing Descriptor Blocks:
0.0.0.0, from Rstatic, Send flag is 0x0
Composite metric is (2560000256/0), Route is Internal
Vector metric:
Minimum bandwidth is 1 Kbit
Total delay is 10 microseconds
Reliability is 1/255
Load is 1/255
Minimum MTU is 1
Hop count is 0
It is now showing up as an internal route even though it shows it was redistributed from static, what does our EIGRP peer R3 see?
R3#show ip route | b Gateway
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.12.0/24 [90/2681856] via 10.1.23.2, 00:02:55, Serial0/0
D 10.1.1.2/32 [90/2560512256] via 10.1.23.2, 00:02:55, Serial0/0
D 10.1.1.3/32 [90/2560512256] via 10.1.23.2, 00:02:55, Serial0/0
D 10.1.1.0/32 [90/2560512256] via 10.1.23.2, 00:02:55, Serial0/0
D 10.1.1.1/32 [90/2560512256] via 10.1.23.2, 00:02:55, Serial0/0
C 10.1.23.0/24 is directly connected, Serial0/0
R3#sh ip eigrp topology 10.1.1.0/32
IP-EIGRP (AS 23): Topology entry for 10.1.1.0/32
State is Passive, Query origin flag is 1, 1 Successor(s), FD is 2560512256
Routing Descriptor Blocks:
10.1.23.2 (Serial0/0), from 10.1.23.2, Send flag is 0x0
Composite metric is (2560512256/2560000256), Route is Internal
Vector metric:
Minimum bandwidth is 1 Kbit
Total delay is 20010 microseconds
Reliability is 1/255
Load is 1/255
Minimum MTU is 1
Hop count is 1
Yes, those static routes on R2 appear to R3 as if they are internal EIGRP routes. Actually, we can remove the "redistribute static" from the EIGRP process as it is no longer required in this instance.
R2#conf t
Enter configuration commands, one per line. End with CNTL/Z.
R2(config)#router eigrp 23
R2(config-router)#no redistribute static
R2(config-router)#end
Strange as it seems, this appears to be a design intent for EIGRP and is documented on Cisco's website about this.
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