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eigrp theory question

Assume we have a hub a spoke deployment. The hub is the HQ of our company. All the spokes have 3 Vlans.

When using eigrp, does the routing table of the spokes include entries for every single vlan of all the other spokes? Shouldn't it just have a route to the hub and the hub has a big routing table? Here is what I'm getting:
HQ
---------
router eigrp 101
 network 10.2.0.0 0.0.1.255
 network 10.20.2.0 0.0.0.255
 network 10.30.2.0 0.0.0.255
 network 10.254.0.0 0.0.0.3
 network 10.254.0.4 0.0.0.3
 no auto-summary
 
 
 
NHS
-----------
router eigrp 101
 network 10.3.0.0 0.0.1.255
 network 10.20.3.0 0.0.0.255
 network 10.30.3.0 0.0.0.255
 network 10.254.0.0 0.0.0.3
 no auto-summary
 eigrp stub connected summary
 
 
 
 
MHS
-----------
router eigrp 101
 network 10.4.0.0 0.0.1.255
 network 10.20.4.0 0.0.0.255
 network 10.30.4.0 0.0.0.255
 network 10.254.0.4 0.0.0.3
 no auto-summary
 eigrp stub connected summary

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jjmartineziii
Asked:
jjmartineziii
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jjmartineziiiAuthor Commented:
Here are the routing tables:

HQ
-----------
hq#show ip route
 
Gateway of last resort is not set
 
     10.0.0.0/8 is variably subnetted, 11 subnets, 3 masks
C       10.2.0.0/23 is directly connected, FastEthernet0/1.100
D       10.3.0.0/23 [90/307200] via 10.254.0.2, 00:25:03, FastEthernet0/0
D       10.4.0.0/23 [90/307200] via 10.254.0.6, 00:11:34, FastEthernet0/1
D       10.30.4.0/24 [90/307200] via 10.254.0.6, 00:11:34, FastEthernet0/1
C       10.30.2.0/24 is directly connected, FastEthernet0/1.102
D       10.30.3.0/24 [90/307200] via 10.254.0.2, 00:25:03, FastEthernet0/0
D       10.20.4.0/24 [90/307200] via 10.254.0.6, 00:11:34, FastEthernet0/1
C       10.20.2.0/24 is directly connected, FastEthernet0/1.101
D       10.20.3.0/24 [90/307200] via 10.254.0.2, 00:25:03, FastEthernet0/0
C       10.254.0.4/30 is directly connected, FastEthernet0/1
C       10.254.0.0/30 is directly connected, FastEthernet0/0
 
 
 
NHS
-----------
nhs#SHOW IP ROUTE
 
Gateway of last resort is not set
 
     10.0.0.0/8 is variably subnetted, 11 subnets, 3 masks
D       10.2.0.0/23 [90/307200] via 10.254.0.1, 00:25:34, FastEthernet0/0
C       10.3.0.0/23 is directly connected, FastEthernet0/1.200
D       10.4.0.0/23 [90/332800] via 10.254.0.1, 00:12:05, FastEthernet0/0
D       10.30.4.0/24 [90/332800] via 10.254.0.1, 00:12:05, FastEthernet0/0
D       10.30.2.0/24 [90/307200] via 10.254.0.1, 00:25:34, FastEthernet0/0
C       10.30.3.0/24 is directly connected, FastEthernet0/1.202
D       10.20.4.0/24 [90/332800] via 10.254.0.1, 00:12:05, FastEthernet0/0
D       10.20.2.0/24 [90/307200] via 10.254.0.1, 00:25:34, FastEthernet0/0
C       10.20.3.0/24 is directly connected, FastEthernet0/1.201
D       10.254.0.4/30 [90/307200] via 10.254.0.1, 00:12:06, FastEthernet0/0
C       10.254.0.0/30 is directly connected, FastEthernet0/0
 
 
 
 
MHS
--------
mhs#show ip route
 
Gateway of last resort is not set
 
     10.0.0.0/8 is variably subnetted, 11 subnets, 3 masks
D       10.2.0.0/23 [90/307200] via 10.254.0.5, 00:12:35, FastEthernet0/0
D       10.3.0.0/23 [90/332800] via 10.254.0.5, 00:12:35, FastEthernet0/0
C       10.4.0.0/23 is directly connected, FastEthernet0/1.300
C       10.30.4.0/24 is directly connected, FastEthernet0/1.302
D       10.30.2.0/24 [90/307200] via 10.254.0.5, 00:12:35, FastEthernet0/0
D       10.30.3.0/24 [90/332800] via 10.254.0.5, 00:12:35, FastEthernet0/0
C       10.20.4.0/24 is directly connected, FastEthernet0/1.301
D       10.20.2.0/24 [90/307200] via 10.254.0.5, 00:12:35, FastEthernet0/0
D       10.20.3.0/24 [90/332800] via 10.254.0.5, 00:12:35, FastEthernet0/0
C       10.254.0.4/30 is directly connected, FastEthernet0/0
D       10.254.0.0/30 [90/307200] via 10.254.0.5, 00:12:35, FastEthernet0/0

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Don JohnstonInstructorCommented:
Unless you're summarizing, all routers will have an entry for each network. Which means that all the routers will have all the networks in their routing tables.

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jjmartineziiiAuthor Commented:
How could I prevent that? What do I need to change?

I would think that stub networks would only need to know where the HUB is. Then the HUB would direct traffic to where it needs to go.
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Don JohnstonInstructorCommented:
Based on your addressing scheme, summarizing the routes on the spoke won't work, so if you want to reduce the size of the spoke routing tables, you'll have to use a default route.

You could send the default route using EIGRP, or just create it manually on each spoke router as a static route.

Either way, you'll still have to create a distribute list to filter out the actual routes.

It would be easier if you changed your addressing so that you could summarize the routes.




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jjmartineziiiAuthor Commented:
So, if I can't summarize the networks since I need that specific scheme (100,101,102,200,201,202). In my case, then, there is nothing I can? I
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Don JohnstonInstructorCommented:
No. You can use a default route. You'll just need to use a distribute list to filter out all the actual routes.
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jjmartineziiiAuthor Commented:
can you show me an example please?

I'd like to see the stub side  and the hub side
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Don JohnstonInstructorCommented:
Here's one way:

(This would be for "NHS")

access-list 66 deny 10.0.0.0 0.255.255.255
ip route 0.0.0.0 0.0.0.0 10.254.0.1
router eigrp 100
 distribute-list 66 in

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jjmartineziiiAuthor Commented:
You the man Mr. Johnston.
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TriCannonCommented:
Don, you mentioned the code below.  But if you create an access list that only has a deny statement in it, then won't it deny ALL traffic?  Because of an explicit DENY that is at the end of every list?


access-list 66 deny 10.0.0.0 0.255.255.255
ip route 0.0.0.0 0.0.0.0 10.254.0.1
router eigrp 100
distribute-list 66 in

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Don JohnstonInstructorCommented:
No, because you don't want to learn the routes through EIGRP. The spoke routers are using a static default route.
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