Confused the CORE Switch's

Question

HI!
PS Throw Light to the following SCenario:
I Have 5 distribution switchs(6509-sup20) connected to Core switch 6509-sup20.the routing protocole its EIGRP.I SENT THE Following Network as a summary to the CORE:
DS1)10.11.0.0:
DS2)10.12.0.0:
DS3:10.13.0.0:
DS4:10.14.0.0:
DS5:10.15.0.0:
Now maybe these confused the core switch.what is the OPTIMUM Way to uncofused the core?& let the core always function properly as well as very good performance
i waiting ur reply!

Answer 1

Under the EIGRP process, the network statement should only include subnets that you want to advertised FROM the router. Subnets that are learned from other devices need NOT to be listed.
If you issue
'sh ip interface brief'
on the core, you can select what networks you want to advertise FROM the core to all devices sharing the same EIGRP AS.
For instance, if the 'sh ip int bri' includes the following networks:
172.16.1.1
192.168.1.1
10.1.1.1
Then your EIGRP process should be like
router eigrp 10
network 172.16.1.0
network 192.168.1.0
network 10.1.1.0
You can also use another method if you have multiple subnets that are within the major network, for instance:
10.11.0.0
10.12.0.0
10.13.0.0
10.14.0.0
could be represented with a single command
router eigrp 10
network 10.0.0.0
no auto-summary.
It will advertise the subnets listed above and not the 10.0.0.0 network because 'no auto-summary' is also part of the EIGRP process.
now if you have the following connected networks:
10.11.0.0 thru 10.14.0.0 AND 10.50.0.0 thru 10.60.0.0 but only want to advertise the 10.11.0.0 thru 10.14.0.0 network then the EIGRP process would be like
router eigrp 10
network 10.8.0.0 0.0.7.255
no auto-summary
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Thanks