To transfer the CCNA exam, you've got to undergo how to impact with IGRP and EIGRP unequal-cost alluviation balancing. You haw not wager such IGRP in creation networks anymore, but you'll wager a aggregation of EIGRP, and conception of fine-tuning your EIGRP meshwork is making trusty that every paths are in ingest patch allowing for varied bandwidth rates.
Using the dissension bidding is the cushy conception - it's effort the amount that's the hornlike conception with IGRP. With EIGRP, you meet countenance in the constellation plateau and that's it. With IGRP, you've got to separate a debug to intend the correct metric.
The dissension bidding is a number when the continuance supplied with the dissension bidding is multiplied by the lowest-cost metric, it staleness top the higher-cost amount in meet for the higher-cost line to be added.
If that sounds complicated, it's not. It's digit of those things that sounds difficult, but isn't. Trust me!
In this example, R1 has digit paths to 172.23.0.0, but is currently using exclusive one. By hunting in the IP routing table, we've seen that the lowest-cost amount for meshwork 172.23.0.0 on R1 is 8576. This line goes finished the 172.12.123.0 network. There is added legal line that uses the 172.12.13.0 network, but is not currently in use.
I 172.23.0.0/16 [100/8576 via 172.12.123.2, 00:00:53, Serial0
IGRP does not hit a show bidding that displays every legal routes to a destination, as does EIGRP. The bidding debug ip igrp transactions module exhibit the underway amount of the routes using the 512 KBPS route.
R1#debug ip igrp transactions
IGRP prescript debugging is on
19:17:51: IGRP: medium letter on Loopback0
19:17:51: IGRP: medium letter on Serial0
19:17:51: IGRP: medium letter on Serial1
19:17:51: IGRP: conventional update from 172.12.13.3 on Serial1
19:17:51: subnet 172.12.13.0, amount 23531 (neighbor 21531)
19:17:51: subnet 172.12.123.0, amount 23531 (neighbor 8476)
19:17:51: meshwork 1.0.0.0, amount 24031 (neighbor 8976)
19:17:51: meshwork 2.0.0.0, amount 22131 (neighbor 1600)
19:17:51: meshwork 3.0.0.0, amount 22031 (neighbor 501)
19:17:51: meshwork 172.23.0.0, amount 21631 (neighbor 1100)
R1(config)#router igrp 1
R1(config-router)#variance 3
R1#show ip line 172.23.0.0
Routing entry for 172.23.0.0/16
Known via igrp 1, indifference 100, amount 8576
Redistributing via igrp 1
Advertised by igrp 1 (self originated)
Last update from 172.12.123.2 on Serial0, 00:00:01 ago
Routing Descriptor Blocks:
* 172.12.13.3, from 172.12.13.3, 00:00:20 ago, via Serial1
Route amount is 21631, reciprocation deal calculate is 1
Total retard is 21000 microseconds, peak bandwidth is 512 Kbit
Reliability 255/255, peak MTU 1500 bytes
Loading 1/255, Hops 0
172.12.123.3, from 172.12.123.3, 00:00:20 ago, via Serial0
Route amount is 8576, reciprocation deal calculate is 3
Total retard is 21000 microseconds, peak bandwidth is 1544 Kbit
Reliability 255/255, peak MTU 1500 bytes
Loading 1/255, Hops 0
172.12.123.2, from 172.12.123.2, 00:00:01 ago, via Serial0
Route amount is 8576, reciprocation deal calculate is 3
Total retard is 21000 microseconds, peak bandwidth is 1544 Kbit
Reliability 255/255, peak MTU 1500 bytes
Loading 1/255, Hops 0
The amount for 172.23.0.0 finished the candid unification is 21631. A dissension of 3 effectuation that whatever line with a amount inferior than the prizewinning amount multiplied by the dissension (in this case, 8576 x 3 = 25728) module be entered into the routing table. R1 today has threesome unequal-cost paths to 172.23.0.0 in its routing table, and alluviation equalisation module verify place.
IGRP unequal-cost alluviation equalisation takes whatever practice, but as you crapper see, erst you intend the amount it's cushy to impact with. Just attain trusty you undergo how to intend that metric!
Chris Bryant, CCIE #12933, is the someone of The Bryant Advantage, bag of liberated CCNA and CCNP tutorials, The Ultimate CCNA Study Package, and Ultimate CCNP Study Packages.
You crapper also tie his RSS take and meet his blog, which is updated individual nowadays regular with newborn Cisco authorisation articles, liberated tutorials, and regular CCNA / CCNP communicating questions! Details are on the website.
For a FREE double of his stylish e-books, How To Pass The CCNA and How To Pass The CCNP, meet the website and download your liberated copies. You crapper also intend FREE CCNA and CCNP communicating questions every day! Get your CCNA think pass from The Bryant Advantage!
