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Summarizing routes is a vital talent to discover to pass the BSCI Examination and obtain a single step nearer to earning your CCNP. The actual binary conversions are only Portion of the take a look at, nevertheless! You’ve got to know the way to correctly implement the summary routes, and that differs from one particular protocol to the following. In the last few CCNP / BSCI tutorials, we’ve checked out utilizing the “space array” and “summary-handle” instructions to conduct OSPF route summarization. These days, we’ll Check out summarizing routes in EIGRP.
We’ll use the subsequent four loopback addresses in this instance:
Loopback 16, sixteen.16.16.16 /32
Loopback 17, seventeen.17.seventeen.seventeen /32
Loopback 18, eighteen.18.eighteen.18 /32
Loopback 19. 19.19.19.19 /32
On R1, we’ll spot these four addresses into EIGRP AS a hundred.
R1(config-if)#router eigrp a hundred
R1(config-router)#network sixteen.sixteen.16.16 0.0.0.0
R1(config-router)#community 17.seventeen.seventeen.seventeen 0.0.0.0
R1(config-router)#community eighteen.eighteen.18.18 0.0.0.0
R1(config-router)#network 19.19.19.19 0.0.0.0
R3 is an EIGRP neighbor of R1, and that router’s EIGRP routing desk now looks like this:
R3#exhibit ip route eigrp
seventeen.0.0.0/32 is subnetted, 1 subnets
D 17.17.seventeen.17 [ninety/2297856] through 172.twelve.123.1, 00:00:29, Serial0
16.0.0.0/32 is subnetted, one subnets
D sixteen.16.sixteen.16 [ninety/2297856] https://socialhattori.com/ by way of 172.twelve.123.one, 00:00:36, Serial0
19.0.0.0/32 is subnetted, one subnets
D 19.19.19.19 [90/2297856] through 172.12.123.1, 00:00:08, Serial0
eighteen.0.0.0/32 is subnetted, one subnets
D 18.18.18.18 [90/2297856] through 172.12.123.one, 00:00:22, Serial0
To conduct guide route summarization, write out the network addresses in binary and afterwards ascertain the point at which the addresses no longer Possess a little bit in popular. For these 4 addresses, It will probably be enough to write out the very first octet in binary:
1600010000
1700010001
1800010010
1900010011
Working from left to correct, the common bits are the primary six bits – 000100xx. In decimal, this worth is sixteen. The summary mask must be determined too, and that worth is derived from putting a “1” during the mask for every widespread bit. With the main 6 bits all established to at least one – 11111100 – the resulting mask is 252.0.0.0. The complete summary address is 16.0.0.0 252.0.0.0.
In EIGRP, the summary tackle is really configured on an interface, not underneath the routing system.
R1(config)#interface serial0
R1(config-if)#ip summary-handle eigrp 100 sixteen.0.0.0 252.0.0.0
02:39:50: %Twin-5-NBRCHANGE: IP-EIGRP 100: Neighbor
172.twelve.123.3 (Serial0) is down: summary configured
172.12.123.2 (Serial0) is down: summary configured
02:40:sixteen: %DUAL-five-NBRCHANGE: IP-EIGRP one hundred: Neighbor
172.twelve.123.2 (Serial0) is up : new adjacency
02:40:17: %DUAL-5-NBRCHANGE: IP-EIGRP 100: Neighbor
172.12.123.3 (Serial0) is up: new adjacency
There’s an instantaneous side result listed here that the majority textbooks depart out. Your EIGRP adjacencies are likely to arrive down Once you configure this summary, but they need to return up rapidly. The key term There exists “need to”. When you configure EIGRP summary addresses on the creation community, you may want to make this happen through non-peak hrs. The timestamps on the above commands show which the adjacencies ended up down for approximately 27 seconds about the NBMA community. That’s about thirty minutes in conclude-user time. 😉
Check out R3’s EIGRP routing table.
D 16.0.0.0/six [ninety/2297856] by using 172.12.123.one, 00:01:46, Serial0
The four summarized routes are no more inside the routing table, plus they are already replaced because of the summary route revealed at the bottom of your routing table. Detect the mask is /5, which happens to be prefix notation for 248.0.0.0.
Being aware of how and why to summarize routes is a worthwhile ability, whatever the protocol in use. But before you decide to take the BSCI exam with your strategy to the CCNP, you should definitely know how to complete summarization with the entire Main protocols!