Problem with PING

[ccthompson]

I seem to have a little problem with my switch. Odd to say the least.

I can ping PCs attached to the switch, but cannot ping the actual switch. But from the switch itself (Cisco IOS) i cannot ping anything but the switch itself.

I cant figure out what this is, or how everything is working. Phones work, data is accessed through the PCs through the network,ect... But the switch is almost like the invisable helper.

Any Ideas?

Thanks!

CCT

[Bobby Thekkekandam]

Hi,

Is the switch's IP address in the same subnet as the connected PCs? If not, then do you have a route between the two subnets?

-Bobby

[ccthompson]

no, it is .1.x, PCs are .10.x

http://forum.cisco.com/eforum/servlet/NetProf?page=netprof&forum=Network%20Infrastructure&topic=LAN%2C%20Switching%20and%20Routing&CommCmd=MB%3Fcmd%3Ddisplay_location%26location%3D.1ddadd99/0

If you check the article above, it is similiar to my problem. I am going ot try this soon, ill let you all know if it works. Thanks for the posts!

[Nicholas Vigil]

Does your switch have its default gateway set? It needs one to communicate to devices on other subnets.

[ccthompson]

it does have the gateway set, same subnet as the switch. ex.

10.1.1.1 is the gateway

10.1.1.2 us the switch

PCs are 10.1.10.x

Thanks for the posts!

[mheusinger]

Is the switch IP address in the same VLAN as your PCs are? If not, then there will be only communication possible, if you have a router performing inter-VLAN routing.

The underlying reason is, that each VLAN represents a single broadcast domain. Thus ARP requests sent to find MAC/IP will not reach from one VLAN to another VLAN. If ARP is not working then no ping will work either. Can you check with "show arp" and "show vlan" in the switch, whether the PCs are in the same VLAN as the switch IP?

If the switch management IP is in the same VLAN make sure network mask and subnets do match and no PC firewall prevents communication.

Hope this helps! PLease rate all posts.

Regards, Martin

[ccthompson]

I have 3 differnt Vlans

Vlan1 is administration (10.1.1.x)

Vlan2 is Data (10.1.10.x)

Vlan3 is Voice (10.1.11.x)

The PCs are all on Vlan2, switch is on Vlan1. The router is doing all the inter-routes, as far as i can tell.

Thanks for the post!

[sundar.palaniappan]

Can you answer the following questions.

1. Do you have a trunk from the switch to the router.

2. Is your router configured with FastEthernet subinterfaces (router-on-a-stick) to do inter-vlan routing?

3. Can you ping the default gateway of the switch from the switch itself?

--Sundar

[ccthompson]

I hope this will give some insite, i did a sh int vlan1:

Vlan1 is up, line protocol is up

Hardware is CPU Interface, address is 0015.fa7f.d8c0 (bia 0015.fa7f.d8c0)

Internet address is 10.127.1.3/24

MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,

reliability 255/255, txload 1/255, rxload 1/255

Encapsulation ARPA, loopback not set

ARP type: ARPA, ARP Timeout 04:00:00

Last input 02:17:56, output never, output hang never

Last clearing of "show interface" counters never

Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0

Queueing strategy: fifo

Output queue: 0/40 (size/max)

5 minute input rate 1000 bits/sec, 2 packets/sec

5 minute output rate 3000 bits/sec, 7 packets/sec

423718 packets input, 30514207 bytes, 0 no buffer

Received 11 broadcasts (0 IP multicast)

0 runts, 0 giants, 0 throttles

0 input errors, 0 CRC, 0 frame, 0 overrun, 11 ignored

995625 packets output, 557546370 bytes, 0 underruns

0 output errors, 2 interface resets

0 output buffer failures, 0 output buffers swapped out

***As for pinging from the switch, no I cannot ping anything from the switch itself. Im just a bit confused I guess, how i can ping machines attached to the switch, but not the switch....??

Thanks for the help everyone!

[mahmoodmkl]

Hi

as per u r output of show interface u r vlan configs and u SVI vlan1 ip are in different subnets.configure them in the same subnet it should work.as u have the range of vlans in the above post.

Thanks

Mahmood

[ccthompson]

I configured the switch to a new IP address.

I gave it 10.1.10.3

Switched the ip default-gateway to 10.1.10.1, this is defined in my router of course. I still cannt ping however!

[mahmoodmkl]

Hi

Can u checked weahther u have IP routing enabled on u r router.

Thanks

Mahmood

[ccthompson]

I do have it enabled. It is very odd.

Like I said above, i have 3 Vlans

1.x (admin)

10.x (data)

11.x (voice)

I have a switch here, 10.1.1.2, and a switch in the other warehouse 10.1.1.3.

From my PC, 10.1.10.100, i can ping the switch here(10.1.1.2) but cannot ping the other warehouse (10.1.1.3).

I can however ping other PCs connected to that switch in the other warehouse.(10.1.1.133,ect...)

We are connect to each other via a Cisco Wireless Bridge, but i dont think thats the problem. Cause when I go to the switch itself, and connect via COM1(hyperterminal) i cannot even ping its own address, or anything else.

Thanks for the post!

[mahmoodmkl]

Hi

What r u using to route beteen u r vlans i think a router on a stick scenario can u verify weather u have configured the correct sub-interface configurations and encapsulation.amd again u r trying to ping 10.1.10.100 from 10.1.1.2 that is a different subnet.can u say which sunbet mask u r using.and verify weather u have specified the correct gateway on the switch.

Thanks

Mahmood

[ccthompson]

The router is performing all the routes Between all the Vlans. All the sub nets are the same (255.255.255.0). The default gateway on the switch is set, to the admin vlan(10.1.1.1)

As for things being on different subnets. As I said above, I also have a 3560 switch here(10.1.1.2). I can ping this from my PC (10.1.10.100)

SO i dont believe that I am having a problem with my routes, as i can ping all the other equipment on that subnet, but this one switch is the only problem.

Thanks!