Ping/Routing Question

I enabled OSPF on all 3 routers, and they can ping each other just fine. Also, the routers can ping the PCs that are in their subnet, but not the PCs on the other subnets. Shouldn't they be able to ping each other?

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Comments

OfWolfAndMan

For each router (Make sure you label), what are your routing statements currently?

bankintheroll

Router 1:
192.168.1.0/24 is variably subnetted, 4 subnets, 2 masks
C 192.168.1.0/26 is directly connected, FastEthernet0/0
C 192.168.1.64/26 is directly connected, FastEthernet0/0.10
C 192.168.1.128/26 is directly connected, FastEthernet0/0.20
C 192.168.1.252/30 is directly connected, Serial0/0
O 192.168.2.0/24 [110/65] via 192.168.1.254, 00:24:17, Serial0/0

Router 2:
192.168.1.0/24 is variably subnetted, 2 subnets, 2 masks
O 192.168.1.0/26 [110/65] via 192.168.1.253, 00:24:42, Serial0/0/0
C 192.168.1.252/30 is directly connected, Serial0/0/0
C 192.168.2.0/24 is directly connected, FastEthernet0/0

Router 3:
192.168.1.0/24 is variably subnetted, 2 subnets, 2 masks
O 192.168.1.0/26 [110/66] via 192.168.2.1, 00:24:55, FastEthernet0/0
O 192.168.1.252/30 [110/65] via 192.168.2.1, 00:24:55, FastEthernet0/0
C 192.168.2.0/24 is directly connected, FastEthernet0/0

thenappyone

do have the default gateway set on the switches?

bankintheroll

thenappyone wrote: »

do have the default gateway set on the switches?

Yes. Switch 1 & 2 has the default gateway of 192.168.1.1. Switch 3 has the default gateway of 192.168.2.1

martell1000

your pcs are in different vlans. you have any subinterfaces configured on the router to do the inter vlan rounting? (since 2950s cont do l3 switching)?

bankintheroll

martell1000 wrote: »

your pcs are in different vlans. you have any subinterfaces configured on the router to do the inter vlan rounting? (since 2950s cont do l3 switching)?

Only PCs connected to Router 1 are in VLANs. VLAN 10 has subinterface 192.168.1.65 and VLAN 20 has 192.168.1.129. All of those PCs can ping each other also (including the PCs in different VLANs).

xnx

Try doing a traceroute, see if gets past the default gateway or not first.

bankintheroll

xnx wrote: »

Try doing a traceroute, see if gets past the default gateway or not first.

Hmm, a tracert from a PC on the left only makes it as far as 192.168.2.1 when trying to get to a PC on the right.

OfWolfAndMan

I actually meant the command you put in after you type in router ospf [asn]. From your design, it should be:
Router3#(config-router)network 192.168.2.0 0.0.0.255 area 0
(I'm not bothering with the public side lol. You gotta have PAT configured and will need a static route).
Router2#(config-router) network 192.168.2.0 0.0.0.255 area 0
network 192.168.1.252 0.0.0.3 area 0
Router 1#(config-router) network 192.168.1.0 0.0.0.255 (Since you have 190 hosts on one end and two on the other)
Do you have all of that?

xnx

Can you draw arrows in paint of what can ping what and then someone may be able to work it out quickly, i'd look properly but i'm off to sleep after 12 hours of studying

xnx

OfWolfAndMan wrote: »

I actually meant the command you put in after you type in router ospf [asn]. From your design, it should be:
Router3#(config-router)network 192.168.2.0 0.0.0.255 area 0
(I'm not bothering with the public side lol. You gotta have PAT configured and will need a static route).
Router2#(config-router) network 192.168.2.0 0.0.0.255 area 0
network 192.168.1.252 0.0.0.3 area 0
Router 1#(config-router) network 192.168.1.0 0.0.0.255 (Since you have 190 hosts on one end and two on the other)
Do you have all of that?

OSPF doesn't use AS numbers by the way, it uses process numbers which doesn't really matter, just make sure it's not 0 :P

xnx

I've had a VERY quick look and Router 2 has no route to Router 3 unless i'm mistaken

OfWolfAndMan

xnx wrote: »

OSPF doesn't use AS numbers by the way, it uses process numbers which doesn't really matter, just make sure it's not 0 :P

Lol yes. Got my EIGRP mixed up with my OSPF :P

bankintheroll

xnx wrote: »

OSPF doesn't use AS numbers by the way, it uses process numbers which doesn't really matter, just make sure it's not 0 :P

R2 and R3 are directly connected.

bankintheroll

OfWolfAndMan wrote: »

I actually meant the command you put in after you type in router ospf [asn]. From your design, it should be:
Router3#(config-router)network 192.168.2.0 0.0.0.255 area 0
(I'm not bothering with the public side lol. You gotta have PAT configured and will need a static route).
Router2#(config-router) network 192.168.2.0 0.0.0.255 area 0
network 192.168.1.252 0.0.0.3 area 0
Router 1#(config-router) network 192.168.1.0 0.0.0.255 (Since you have 190 hosts on one end and two on the other)
Do you have all of that?

I didn't even bother with the public side either at this point. I actually configured OSPF slightly different. Jeremy (from CBTNuggets) said the best practice is to use the actual router interface IP and use 0.0.0.0 as the wildcard mask. Is this correct?

bankintheroll

To be more specific, here are the network commands I used in router ospf 1:

Router 1:
network 192.168.1.1 0.0.0.0 area 0
network 192.168.1.253 0.0.0.0 area 0

Router 2:
network 192.168.2.1 0.0.0.0 area 0
network 192.168.1.254 0.0.0.0 area 0

Router 3:

network 192.168.2.2 0.0.0.0 area 0
network 68.200.93.217 0.0.0.0 area 0

Is this wrong for this particular topology?

EdTheLad

No its not wrong, the network command is used to indicate which interfaces will run ospf. If you use the address with 0.0.0.0 mask you are specifying a single address. Lets say you have 4 interfaces using a 192.168.1.x/30 subnet, i.e. subnets 0,4,8,12 you could use network statement 192.168.1.0 0.0.0.15.
If you want to enable ospf on all interfaces you can use "network 0.0.0.0 255.255.255.255" .
It all comes down to control, lets say you have a router with two interfaces 10.0.0.1/30, 10.0.0.5/30; ospf network statement 10.0.0.0 0.0.0.255, both interfaces are enabled for ospf. Now later you add an interface 10.0.0.9, this will automatically have ospf enabled, maybe you don't want that. You also probably wouldn't want hundreds of network statements, this is where panning comes in.

bankintheroll

Thanks Ed. In the real world, is it best to do what I have practiced in this example?

On another note, I'm still not quite sure why I can't ping from the left network to the right. It says destination host unreachable when I try that.

EdTheLad

It depends how many interfaces you have to enable ospf on, but what you have done is perfectly fine for the real world as you only have afew interfaces and you have complete control over which interfaces have ospf enabled.

I had a quick look at your setup and i can point afew things out you should fix.

1) On Router1, you have a physical interface with 2 subinterfaces, remove the config from the main interface i.e. 192.168.1.1/26. You are missing ospf network statements for 192.168.1.65 and 192.168.1.129.
2) Make sure 2950-1 and 2950-2 have vlans 10 and 20 configured and allowed on the trunk between the 2 switches and between switch1 and router1.
3)Make sure PC1-6 have the correct DFGW configured i.e .65 or .129

See how you go with that.

bankintheroll

Ed,

As soon as I saw your advice on using OSPF statements on the R1's subinterfaces, I had a strong feeling that was my problem. You were right. Thank you very much for taking the time to help me! Everything pings great now!