Why cant I ping to different intereface when route is there

Unanswered Question
Feb 5th, 2008

All our devices are on vlan 1 in one building. However, we are trying to implemenet a new link. All devices

are using the 192.168.1.0 Network. However we are trying to add 192.168.21.0

On our 2950 switch we have 3 routers attached

Users have are given 2 default gateways via DHCP-One Gateway From Router A and the other from Router B

Router A-192.168.1.252

Router B-192.168.1.245

Router C will be the new subnet and Gateway -192.168.21.236

From Router B I can ping the 192.168.21.236 interface.

RouterB#sh ip route 192.168.21.236

Routing entry for 192.168.0.0/16, supernet

Known via "static", distance 1, metric 0

But from router A I cant

router A>sh ip route 192.168.21.236

% Network not in table

From my desktop on the 192.168.1.X subnet, I can ping the 192.168.21.236 interface. Perhaps I using Router B gateway when I do this??

However, when I switch over to the 192.168.21.X subnet, and use the .21.236 on router C-as my default gateway I CAN'T ping Router A but can Ping router B

BUT I have a route to the entire 192.168.1.0 network...via connection to router B. This would include a route to router A

Router A-192.168.1.252

Router B-192.168.1.245

Router C #sh ip route 192.168.1.252

Routing entry for 192.168.1.0/24

Known via "connected", distance 0, metric 0 (connected, via interface)

Redistributing via ospf 100

RouterC #ping 192.168.1.252

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 192.168.1.252, timeout is 2 seconds:

...

Success rate is 0 percent (0/3)

RouterC#ping 192.168.1.245

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 192.168.1.245, timeout is 2 seconds:

!!!!!

However, only when I log into router B-can I ping router A

One thing I failed to mentioni is that Router C has a Primary and Secondary interface.

On Router A-the secondary is pingable but the primary is not-it is also showing connected even though there is a switch between them

RouterA#sh ip route 192.168.1.236

Routing entry for 192.168.1.0/24

Known via "connected", distance 0, metric 0 (connected, via interface

Redistributing via eigrp 1

Routing Descriptor Blocks:

* directly connected, via FastEthernet0/0

I'm stumped

I see no access lists applied to any interface on Router A that would deny ICMP

I have this problem too.
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Edison Ortiz Tue, 02/05/2008 - 11:24

Router B has a static route to Router C as shown here:

RouterB#sh ip route 192.168.21.236

Routing entry for 192.168.0.0/16, supernet

Known via "static", distance 1, metric 0

Add the same static route on Router A.

HTH,

__

Edison.

nygenxny123 Tue, 02/05/2008 - 18:43

Hi Edison,

Since I can ping the secondary interface on Router C from Router A. Shouldint I also

be able to ping the primary interface on Router C from Router A?

router c

secondary 192.168.1.236

primary 192.168.21.236

Edison Ortiz Tue, 02/05/2008 - 21:04

The secondary IP is on the same subnet as the primary IP on Router A, no need for routing.

On Router A, do the following:

ip route 192.168.21.0 255.255.255.0 192.168.1.236

HTH,

__

Edison.

nygenxny123 Wed, 02/06/2008 - 06:08

Here is the sh ip route to the primary ip interface

RouterA#sh ip route 192.168.21.0

% Network not in table

Here is the secondary IP

Router A#sh ip route 192.168.1.236

Routing entry for 192.168.1.0/24

Known via "connected", distance 0, metric 0 (connected, via

Redistributing via eigrp 1

Routing Descriptor Blocks:

* directly connected, via FastEthernet0/0

Route metric is 0, traffic share count is 1

the default route for router A actually goes to our ISP.

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