CCNA - a little routing and subnetting help ^^; diagram included!

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Akubane

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Hey guys. Just started working on my CCNA and i'm having a bit of trouble with routing this network.
I jumped into the course late so I missed subnetting and have been trying to work through it on my own. Think I got most of it down though.
It's no big deal if I don't get it down since we weren't supposed to really do anything till monday in class but I didn't feel like waiting around to try and follow along. Better if I can do it, get used to it, then go alone during class where I can expand upon my understanding.
We're using the CCNA network Visualizer 6 for this. (Really cool program btw lol)
http://img228.imageshack.us/img228/9923/ccnalab.jpg (seems the forum doesnt allow thumbnails. image is 1600x900)
Anyway on to the problem.
-Purple underlined IP's are concrete.
-I need to assign the missing IP addresses (yellow) with valid IPs, and all the hosts with valid IP's.

I think I got the hosts done properly, and they can all communicate on their own subnetworks.

Focusing on PEI on the right:
The problem starts when Hosts H01-H05 on PEI01 try to ping PEI Router Interface F0/0 (18.233.141.69) or any other hosts on the network. Nothing gets passed PEI01 switch interface F0/1 (pink arrow).
The in program troubleshooter says the interface is down, while the console says its up. Does the switch interface need an IP address? I didn't think it did but I tried adding one through the switches console just to see but it just returned an error.
I have the PEI router interface F0/0 set up as H01-H05's default gateway.

As far as communicated between router -> routers, and hosts -> hosts on other subnets:

I had PEI S0/1 @ 17.13.14.14/30
XFH01 S0/0 @ 13.100.200.158/30
FTN S0/1 @ 20.200.103.189/30

I assumed (perhaps incorrectly) PEI S0/1 should be on the same subnet as HFX01 S0/1 (same with other routers) but it didn't seem to work. Routers could ping their neighbours, but not hop one and ping the others. i.e. PEI couldnt ping FTN.

I set up RIP as the routing protocol and gave it the addresses on the neighbouring interfaces but it didn't seem to work.

Just in case, i tried giving the missing router IP interfaces completely separate IP addresses but that didn't seem to make a difference either.

Questions:
1)Was my assumption about the neighbouting router interfaces being on the same subnet correct? i.e. 17.13.14.13/30 ---------- 17.13.14.14/30 ? If not could someone give an example of a valid IP address for the PEI S0/1 router interface?
2)Did I subnet the hosts properly? I did the math for calculating block size and made sure I didnt use the subdomain address or broadcast address. Beyond that I don't know ^^;;
3) Pink arrow switch interface F0/1. Does it need an IP address? Would that be the default gateway instead of the router PEI F0/0? Or was choosing the router interface as the default gateway correct?

Thanks for any help anyone can offer. im stumped.
 
first i would grab a subnet calc and see if the addressing is correct. all hosts on PEI should be assigned to the same subnet. F0/1 on PEI01 shouldn't need an ip. it should should have routers interface ip saved in the mac address table of the switch.

i suspect the problem with pinging other routers is a misconfig with router's default gateways.
 
ok was messing around with it this morning and figured out why the routers weren't communicating. When I configured RIP I misunderstood how it was supposed to work and input the the actual neighbouring IP address, and not the address of the subnetwork itself. So i reconfigured rip with the proper network addresses and they're communicating perfectly now. Turns out i was right to keep each interface on the same network.

upodated:
http://img34.imageshack.us/img34/3561/subnetworkcurrent.png

I didn't think the switch interface needed an IP.

The hosts are all subnetted properly it seems. I've got a good grip on how to do it now thankfully, and the calculator verifies the correct valid ip ranges.

The hosts still can't ping the router though. its not just that they cant ping other routers and hosts on other subnets. Hosts H01-H05 and H12-H13 can't ping their own router PEI.

The only thing I can think of is that i've misconfigured the default gateway, though I don't see why that would prevent them from pinging the router thats on the same subnet. And i don't see why that router interface wouldn't be the proper gateway address.

after digging around i thought the problem might be that ip datagram forwarding was disabled but cisco says its enabled by default.

http://img580.imageshack.us/img580/75/subnetworkcurrentnetdet.png
here's whats the troubleshooter says.

I dont see how it can't find it. the valid host range for that subnet x.x.x.64 is 18.233.141.65 - 18.233.141.126

The router and hosts all fall within. ; ;

Any ideas?

Here's the routers ip route and ip interface:
http://img690.imageshack.us/img690/3811/routingtable.png

edit~~ I just found out that its only the PEI subnetwork that isnt functioning properly. hosts H06-H11 can all communicate properly with every other host/router on the network ~including~ PEI Interface F0/0.
 
i find your edit comment to be contradicting. I figure all hosts with a default gateway of the PEI F0/0 to be the PEI subnetwork. However, you say the hosts can now ping each other and PEI F0/0. Can you clarify what's currently not working properly?
 
Sorry about that. Didn't make it clear.

All hosts on the subnetwork PEI (H01 to H05 and H12 to H13) cannot communicate with their router PEI (default gateway) or anythign outside of it.

All other hosts (H06 to H11) on the other subnetworks function as intended. They can communicated outside their networks. What I found odd is that they can also communicate with all 3 interfaces on PEI, which includes F0/0 (The default gateway for the subnetwork that isn't working)

It's like all communication stops at the switch PEI01. Though I didnt do anything beyond changing the hostname, as I did with the other switches.

Hope thats worded better.

edit~ Just in case i did something during initial setup that i didn't remember, i just deleted the router and reconfigured it from scratch, twice, and still no luck.
 
you can further investigate by answering the following questions

can you ping the hosts 1-5, 12 & 13 from PEI's F0/0? if yes, check inbound ACL on PEI F0/0.

can hosts 1-5, 12 & 13 ping each other? if yes, focus on router int config.

follow-up q

can you post the run config for PEI?
 
Could you post up the running config on PEI?

edit: while I was away fixing someone's mac, office beat me to it :p
edit edit: also, knowing any config changes you made on PEI01 would help too. Are you managing that switch at all?
 
OK no, I can't ping the hosts 1-5 and 12-13 from pei.

Yes those hosts can ping each other

The only config change I made to PEI01 is changing the hostname.

As far as the routers access list, show access-list didn't return anything. I haven't manually added any entries.

Gonna head off to class, i'll keep pokin' around when i get there. Thanks a ton guys

running config:
Building configuration...
Current configuration : 625 bytes
!
version 12.2
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname PEI
!
enable secret 5 $1$u76B$IOFVJ7VxfVXYVpGDrFTcI0
!
ip subnet-zero
!
!
!
!
!
interface FastEthernet0/0
ip address 18.233.141.69 255.255.255.192
no ip directed-broadcast
!
interface Serial0/0
no ip address
no ip directed-broadcast
shutdown
!
interface FastEthernet0/1
ip address 15.132.254.174 255.255.255.252
no ip directed-broadcast
!
interface Serial0/1
ip address 17.13.14.14 255.255.255.252
no ip directed-broadcast
!
router rip
network 15.0.0.0
network 17.0.0.0
network 18.0.0.0
!
!
ip classless
no ip http server
!
!
!
line con 0
line aux 0
line vty 0 4
login
!
end
 
Hmm, it's been so long since I've had to deal with this :p time to break out the textbooks
It looks like your router config is fine.

'no shut' command issued on F0/1 on PEI01?
 
yup the interface is enabled.

PEI01>en
PEI01#show ip int bri
Interface IP-Address OK? Method Status Protocol
Vlan1 unassigned YES unset down down
FastEthernet0/1 unassigned YES manual up up <------------------- *
FastEthernet0/2 unassigned YES manual up up
FastEthernet0/3 unassigned YES manual up down
FastEthernet0/4 unassigned YES manual up up
FastEthernet0/5 unassigned YES manual up down
FastEthernet0/6 unassigned YES manual up up
FastEthernet0/7 unassigned YES manual up down
FastEthernet0/8 unassigned YES manual up up
FastEthernet0/9 unassigned YES manual up down
FastEthernet0/10 unassigned YES manual up down
FastEthernet0/11 unassigned YES manual up up
FastEthernet0/12 unassigned YES manual up up
PEI01#
 
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