Show IP route: displays the entire routine table
Show ip route eigrp: shows only eigrp entries in the
routine table
Show ip eigrp neighbors: show all EIGRP neighbors
Show ip eigrp topology: show entries in the EIGRP table
Debug eigrp packet: show hello packets sent/received
between adjacent routers
Debug ip eigrp notification: shows eigrp changes and
updates as they occur on your network.
Below is the display of the show ip route command on Cisco router:
HQ#show ip
route
10.0.0.0/30 is
subnetted, 3 subnets
C 10.10.1.0
is directly connected, Serial0/0/1
C 10.10.10.0
is directly connected, Serial0/0/0
D 10.20.20.0 [90/2681856] via 10.10.10.2,
00:31:47, Serial0/0/0
[90/2681856]
via 10.10.1.2, 00:28:25, Serial0/0/1
172.17.0.0/24
is subnetted, 1 subnets
D 172.17.1.0 [90/2172416] via 10.10.10.2,
00:26:51, Serial0/0/0
C
192.168.10.0/24 is directly connected, FastEthernet0/0
D 192.168.20.0/24 [90/2172416] via 10.10.1.2,
00:26:44, Serial0/0/1
C
200.165.199.0/24 is directly connected, Loopback0
HQ#
The display above shows all the routes there is in the
routing table. The Cs are directly connected. The Ds (DUAL) are the EIGRP
routes and the default distance is 90, which represents internal eigrp routes.
Show ip eigrp
neighbors command:
HQ#show ip eigrp neighbors
IP-EIGRP neighbors for process 1
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.10.10.2 Se0/0/0
12 00:39:13 40 1000 0
14
1 10.10.1.2 Se0/0/1 10
00:35:48 40 1000
0 14
HQ#
The above display of the show ip eigrp neighbors command.
i. The H field shows the order in which a neighbors
is discovered.
ii. The Hold time is how long the local router (this
router) have to wait for for a hello packet to arrive from a neighbor.
iii.
The uptime shows how long adjacency with a
neighbors has been established
iv. The SRTT field is the smooth round trip timer.
This means the time it takes for this router to link with a neighbor and back.
It normally has a value which is used to determine how long a waiting time
after a multicast reply from a neighbor. If The router did not receive a reply
in time, it will result in using a unicast in order to complete the
communication.
v. The RTO (Retransmission Time Out) field is the
amount of time EIGRP waits before retransmitting a packet.
vi.
The Q value field shows the number of messages
in the queue. Taking note that large values means problem.
vii.
The Seq field indicates the sequence number of
the last update from a neighbour. This in a way is used to maintain
synchronization and to avoid duplicate messages.
The Show IP eigrp Topology:
HQ#show ip
eigrp topology
IP-EIGRP Topology Table for AS 1
Codes: P - Passive, A - Active, U - Update, Q - Query, R
- Reply,
r - Reply
status
P 10.10.10.0/30, 1 successors, FD is 2169856
via
Connected, Serial0/0/0
P 10.20.20.0/30, 2 successors, FD is 2681856
via
10.10.10.2 (2681856/2169856), Serial0/0/0
via
10.10.1.2 (2681856/2169856), Serial0/0/1
P 10.10.1.0/30, 1 successors, FD is 2169856
via
Connected, Serial0/0/1
P 192.168.10.0/24, 1 successors, FD is 28160
via
Connected, FastEthernet0/0
P 172.17.1.0/24, 1 successors, FD is 2172416
via
10.10.10.2 (2172416/28160), Serial0/0/0
P 192.168.20.0/24, 1 successors, FD is 2172416
via
10.10.1.2 (2172416/28160), Serial0/0/1
P 200.165.199.0/24, 1 successors, FD is 128256
via
Connected, Loopback0
HQ#
On the display above, each route is preceded by a P,
which indicates that the route is in a passive state which is a good thing.
If a route is preceded by A (active state), that shows
that the router has lost connection to the route or network. Looking carefully,
you will find two numbers in parentheses, the first is the feasible distance (FD),
and the second is the advertised distances a remote network
The FD (Feasible Distance) indicates feasible distances
to each remote network plus the next hop router in which a packet takes to its
destination.
The successor indicates only one successor to a remote
network Iin some cases, there are feasible successor or back-up route to a
network which will be displayed on a large network with multiple routes configured,
like that on 10.20.20.0 network above. Both routes can be found in the topology
table, but only that with the lowest metrics will be copied and placed into the
routing table.
