Switch not pingable, router is

joshbgosh10592 · ‎11-11-2015

Hello everyone. I'm a newbie starting a CCNA lab with general Cisco knowledge. I have a 3550XL and 3640 Router with 2, 2-port Ethernet modules inserted (E0/0,0/1 are currently what I'm using.)

I have the router up and running, pingable from my LAN (right now, everything including my lab is all in the same subnet (10.9.xx\16). My gateway to the Internet is 10.9.0.1

The router is 10.9.0.160, and switch (MDF) is 10.9.0.181. Router can ping my LAN, and 8.8.8.8.

The switch cannot ping anything but itself. Router's Uplink is E0/0, and the MDF is connected to E0/1, 0/48 on the switch.

Sho cdp nei shows the other device (from router, it sees switch, vice versa), with the IP address I assigned.

Have any ideas? The config is below:

Router#sho run | b Ethernet

interface Ethernet0/0
description Uplink
ip address 10.9.0.160 255.255.0.0
half-duplex
no mop enabled
!
interface Ethernet0/1
description To MDF
no ip address
half-duplex
!

<-------------------------------------->

ip default-gateway 10.9.0.1
ip http server
no ip http secure-server
ip route 0.0.0.0 0.0.0.0 10.9.0.1
ip route 0.0.0.0 0.0.0.0 Ethernet0/0 10.9.0.1

Switch:

interface FastEthernet0/48
description Uplink toCRouter
switchport mode dynamic desirable
!

interface Vlan1
ip address 10.9.0.181 255.255.0.0
!

ip default-gateway 10.9.0.160
ip classless
ip http server
ip http secure-server
!

Ganesh Hariharan · ‎11-12-2015

Hello ,

The command on interface vlan 1 ip address is only to mange the switches from local LAN.

what vlan are the host are configired, it shoudl be in vlan 1 to connect the switch on same vlan.

and in router you can have ip route 0.0.0.0 0.0.0.0 ISP public ip rather ip default gateway.

Hope it Helps..

-GI

Rate if it Helps

joshbgosh10592 · ‎11-13-2015

The router is inside my LAN. The only uplink the router has is through E0/0, which runs into my ISP's gateway with the IP address of 10.9.0.1\16.

Switch: int Vlan1 IP address is 10.9.0.181\16

The router, I can't seem to get into the int vlan1. I don't suspect the router is at fault, or at least the config of the IP address, since I'm able to ping into it, and out of it. I could be wrong however...

The router IP address is set on E0/0. Maybe it should be set somewhere else? Maybe Loopback0 instead of E0/0?

InayathUlla Sharieff · ‎11-15-2015

Josh,

Suppose your network looks like this:-

ISP

|(10.9.0.1)

|

Router

|E0/0(10.9.0.160 255.255.0.0)

|

Switch ( vlan 1:- 10.9.0.181\16)

So the vlan concept only comes in the Switching technology. Hence now you have configured the switch vlan 1 to be in the same network it should be albe to ping the router ip address if it has been configured correctly.( show vlan id and see the uplink port is showing under the id vlan 1.) Check the ip address and subnet mask once again to verify we are not missing anything.

Coming down to your questions:-

=======================

The router is inside my LAN. The only uplink the router has is through E0/0, which runs into my ISP's gateway with the IP address of 10.9.0.1\16.

Answer:- this looks good.

2)

Switch: int Vlan1 IP address is 10.9.0.181\16

The router, I can't seem to get into the int vlan1. I don't suspect the router is at fault, or at least the config of the IP address, since I'm able to ping into it, and out of it. I could be wrong however...

Answer:- Router doesnt have concept of Vlan( but we do the same using the subinterfaces if we have to do the intervlan routing).

3)

The router IP address is set on E0/0. Maybe it should be set somewhere else? Maybe Loopback0 instead of E0/0?

Answer:- I hope your E0/0 is connected direclty to the switch f0/48 interface? If yes please check the subnet mask configured between the interfaces ?

Check the Interface status on both the ends? show vlan id on switch and show span tree for that vlan 1?

There is nothing extra requrired if you have directly connected interface between the switch and router having it on the same broadcast domain.

HTH

regards

Inayath

joshbgosh10592 · ‎11-16-2015

Hi Inayath,

I'll have to move the console cable over when I get home tonight (I have the router's aux connected to the switch's con port, but I can't get reverse telnet to work either. That's another issue I'm working on...)

1) At least one thing is right! Lol

2) Since I didn't configure VLANs or anything like that on the router, so I assume VLANs (at least on the router) aren't at fault.

3) No, E0/1 is connected directly to F0/48, with no ip address, which is what we use at work. I did set E0/1 at one time to be a .161, to which made no difference.

Interface status was up/up on both, last I checked. Also last I checked, vlan1 was assigned to all 48 ports, as that was default.

Also probably noteworthy, I was able to get into the switch when it was wired into my home network alone. So if I have my computer connected to the switch directly, I can get into it.

Richard Bradfield · ‎11-18-2015

Hi Josh

The problem is that you do not have an IP address on e0/1 of the router. and e0/1 cannot be set as a switchport. Therefore I would suggest you setup a completely different subnet between the switch and the router e0/1

If you want to continue to use the 10.9.0.x network then

remove Ip adress from e0/0 and put on e0/1 connect the ISP directly to another port on the switch configured as Vlan 1

joshbgosh10592 · ‎11-18-2015

Hello again Richard.

I eventually did figure that out, and created a completely different network based off of what you said. I made E0/0 10.9.0.160\16 and E0/1 to be 92.168.1.1\24.

So, to get what I was originally aiming for, meaning that the ports (other than the WAN) did not have an IP, would the loopback have to be set? I'm just trying to figure out how another environment works, and was trying to dupliciate it.

Richard Bradfield · ‎11-18-2015

The 3640 just has 2 ethernet ports which are L3

you can have " ip address unnumbered loopback 0" to use the loopback address on the interface.

HTH

Richard

joshbgosh10592 · ‎11-16-2015

Ok, so now that I'm home, I can do more information digging.

Sw int f0/48 is vlan 1 by default, and shows as up/up on both ends.

The subnet mask of E0/0 and vlan1 on the switch do match.

I'm assuming the problem might be that the e0/1 doesn't have an IP address. However, I'd like to be able to set the IP address on the router, and not bind it to a port. Is that the Loopback0?