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34
Replies

cannot ping LAN IP

xue.wen
Level 1
Level 1

Hi, I have a cisco 3825 router with two GE interfaces. GE0/0 is connected to a switch through ethernet cable. I have configured the GE0/0 interface with IP address. I have also configured static route for the local network. However, now I can only ping the GE0/0's own IP from the router. Here are the running-config:

hostname Router

!

boot-start-marker

boot-end-marker

!

!card type command needed for slot 2

enable secret 5 $1$4gxa$sykc0mcaxpCIrGc86i1ZE.

enable password 7 012156114F5814

!

no aaa new-model

ip cef

!

!

!

!

!

!

!

username routeradmin password 7 113B4910034119

!

!

!

!

interface GigabitEthernet0/0

description Internal

ip address 10.1.52.4 255.255.255.0 secondary

ip address 10.1.52.5 255.255.255.0

ip nat inside

duplex auto

speed auto

media-type rj45

no cdp enable

!

interface GigabitEthernet0/1

no ip address

shutdown

duplex auto

speed auto

media-type rj45

!

no ip forward-protocol nd

ip route 0.0.0.0 0.0.0.0 10.1.52.1

ip route 10.1.52.0 255.255.255.0 10.1.52.1

!

no ip http server

no ip http secure-server

!

!

control-plane

!

!

line con 0

password 7 012156114F5814

login

line aux 0

password 7 1425421E185738

login

line vty 0 4

password 7 133747071F5F16

login local

!

scheduler allocate 20000 1000

!

end

The 10.1.52.1 is the current gateway on the 10.1.52.x LAN.

Can anyone please help here?

Thanks a lot!

1 Accepted Solution

Accepted Solutions

My friend,

i believe that without encapsulation you will not communicate with your internal vlans.....

Good Luck

Alessio

View solution in original post

34 Replies 34

first

you don't need of static route for the local network it's directly connected

second

are you sure that do you have correctly connectivity with the rest of lan?

in the ports of switch are configured vlan?

regards

Thanks for your reply.

Yes, there are vlan configured in the switch ports. However, we are using layer 3 switch and IP routing is enabled among different vlans. And I even cannot ping the IP address within the same vlan.

Jason Dance
Level 1
Level 1

Can you try removing that static route to see if you can ping again? If it still doesn't work try removing the Nat command from the ge0/0 interface also.

Thanks for your reply.

I tried to remove the static route and the nat command, and I even changed one cable. However, it still doesn't work. I cannot ping any local IP connected on the same switch from the router.

Do you have any other suggestion? Thanks!

One quick update:

I tried to connect GE0/0 directly to host, and then I can ping the GE0/0 IP (10.1.52.4) from that host.

Hope this gives more clue.. Any suggestion is high appreciated.

jimmysands73_2
Level 5
Level 5

You have IP NAT INSIDE, where are you other nat statements?

      

and

ip address 10.1.52.4 255.255.255.0 secondary

ip address 10.1.52.5 255.255.255.0

You secondary address in in the same subnet as the original?  Bad design.

Thanks Jimmy for pointing that out.

I followed Jason's suggestion to remove that IP NAT INSIDE command. I also removed that secondary ip address. But either of them helped..

Any other ideas? Thanks.

To which to  belongs the VLAN subnet 10.1.52.4 / 24? If not for the native vlan (is it vlan 1?), then you need to configure subinterfaces on the router

There are two vlans in the subnet 10.1.52.4 / 24, vlan 1 and vlan 3. We have two switches and IP routing are enabled on the switches so that hosts in the two vlans can visit each other. Can you elaborate a little bit how should I configure subinterfaces on the router? Do I still need to assign ip address for GE0/0? or should I just go for GE0/0.1, GE0/0.2? simple example would be very hlepful.

Thanks.

Please show the output "Show vlan br" and tell me what ports connected to the host that you are testing and a router.

If they are in a different vlans, we should be configure subinterfaces

where should I initiate this command? I don't see such command either on our switch (DELL powerconnect) or router (cisco 3825).

But I can answer your question about the host and router, they are connected to the same switch and to ports that are in the same vlan (vlan 1). The current gateway (10.1.52.1) is on another switch and in another vlan (vlan 3).

Do I need to configure subinterfaces? Thanks.

This command must be entered on the switch, but you switch is-non Cisco. Pls, double check that host and router in a same subnet and same vlan.

Subinterfaces needed in a case when used non-native vlan.

Also, we can try to put the one  host on the switch to the test vlan 33, create a subinterface on  router in vlan 33,  test the connection.

I will try your suggestion.

And I just double checked, the host and router (GE0/0) are in the same subnet and same vlan, which is vlan 1 and should be default vlan. How do I know whether it is non-native vlan?

On you router native vlan is 1, by default. I think, on your switch it is  untagged port,but i'm not familiar with dell switches

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