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Need Help adding a 2950G 1

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jmuttart

ISP
Jul 22, 2009
11
CA
We have recently purchased a used Cisco 2950G and using the network assistant we can see other switches plugged into it via trunk ports but am unable to see the new one from any of the other switches. Can ping from the new to the old but not from the old to the new one. We have wiped the config and setup it up again fresh with just the management vlan and its IP with no success any ideas as to what could possibly be wrong
 
post the config of the new one here

I hate all Uppercase... I don't want my groups to seem angry at me all the time! =)
- ColdFlame (vbscript forum)
 
Shamrock#show conf
Using 1810 out of 32768 bytes
!
version 12.1
no service pad
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname Shamrock
!
enable secret 5 $1$zCjw$AeH/S/oWKId5h1adDJfA00
enable password **********
!
wrr-queue bandwidth 10 20 70 1
wrr-queue cos-map 1 0 1
wrr-queue cos-map 2 2 4
wrr-queue cos-map 3 3 6 7
wrr-queue cos-map 4 5
mls qos map cos-dscp 0 8 16 24 32 46 48 56
ip subnet-zero
!
!
spanning-tree mode pvst
no spanning-tree optimize bpdu transmission
spanning-tree extend system-id
!
!
!
!
interface FastEthernet0/1
switchport access vlan 555
!
interface FastEthernet0/2
switchport access vlan 555
switchport mode access
mls qos trust cos
auto qos voip trust
macro description cisco-switch
spanning-tree link-type point-to-point
!
interface FastEthernet0/3
switchport mode access
!
interface FastEthernet0/4
!
interface FastEthernet0/5
!
interface FastEthernet0/6
!
interface FastEthernet0/7
!
interface FastEthernet0/8
!
interface FastEthernet0/9
!
interface FastEthernet0/10
!
interface FastEthernet0/11
!
interface FastEthernet0/12
!
interface FastEthernet0/13
!
interface FastEthernet0/14
!
interface FastEthernet0/15
!
interface FastEthernet0/16
!
interface FastEthernet0/17
!
interface FastEthernet0/18
!
interface FastEthernet0/19
!
interface FastEthernet0/20
! interface FastEthernet0/21
!
interface FastEthernet0/22
!
interface FastEthernet0/23
!
interface FastEthernet0/24
description Trunk to Sw2
switchport mode trunk
speed 100
duplex full
!
interface GigabitEthernet0/1
!
interface GigabitEthernet0/2
!
interface Vlan1
no ip address
no ip route-cache
shutdown
!
interface Vlan555
ip address 172.16.125.31 255.255.0.0
no ip route-cache
!
ip http server
!
line con 0
line vty 0 4
password r2sw1TCH
login
line vty 5 15
password r2sw1TCH
login
!
!
end


I can ping any cisco switches on the 172.16.0.0 network put can not ping this cisco switch (172.16.125.31) from any of those switches. I can also get on the internet from this switch (through 5 others to get to the gateway) so I know the trunking is working but can not manage it unless plugged into it directly.

Thanks

Jason


 
it's got to be an issue with not having the ip default-gateway <gateway ip> in there. I'm not 100% clear on your network setup and whether or not you are trying to access the VLAN555 SVI from the 172.16.0.0/16 address space.

I hate all Uppercase... I don't want my groups to seem angry at me all the time! =)
- ColdFlame (vbscript forum)
 
VLAN555 is the management Vlan with the IP scheme of 172.16.0.0 so no default gateway is needed. I am just wondering if there is an issue with these switches as I have two of them that do the same thing we have set up at least 20 others with no issues at all but for whatever reason these two just do not work properly.
 
>but am unable to see the new one from any of the other switches

Verify CDP is running.

The only issue I’ve had with my 2950G and VLANs after clearing and rebuilding the flash is that VTP is running version 1.

ip default-gateway command on a L2 device is only used for management access
 
cdp is layer 2 and i dont think default gateway is only used for management access interface vlan 1 is used for management by default so lets say its 1.1.1.1 so you telnet to that, where does it send the return traffic? 1.1.1.1? or the default gateway?

you can ping everything in 172.16.0.0 because you are broadcasting that and anyone that will listen will reply.

you need a default gateway
 
>i dont think default gateway is only used for management access

in L2 yes

in L3 no

>cdp is layer 2

indeed. this is why when you connect two switches back-to-back they know each others information. if you are unable to obtain this information from a neighboring switch you may want to verify CDP is running.
 
ok so when you telnet to vlan 555 at 172.16.125.31 where does the return traffic go?
 
default-gateway. This is why it doesn’t work. As described above the only way to gain telnet access is by plugging into a local switchport.
 
The ip address is for mgt only on the switch , if you try to telnet to it from off the subnet that your mgt is on and there is no default gateway on the 2950 then it doesn't know where to send the packets to be routed thus you cannot telnet or ping to it from off the mgt subnet, put the L3 default gateway address in and it should work as others have said.
 
i agree...

<quote>North323 (TechnicalUser)
22 Jul 09 15:14
cdp is layer 2 and i dont think default gateway is only used for management access interface vlan 1 is used for management by default so lets say its 1.1.1.1 so you telnet to that, where does it send the return traffic? 1.1.1.1? or the default gateway?

you can ping everything in 172.16.0.0 because you are broadcasting that and anyone that will listen will reply.

you need a default gateway
</quote>
 
Simple test: add the default GW and see what happens.

The fact of the matter is this - all his switches have VLAN555 addresses on them (?confirm) so if he is telnetted to one switch, from that switch he can ping all the others, and none of that network traffic has anything to do with the default GW.
If this isn't working, then he is having unusual ARP problems.

I suspect, however, that the real problem lies in the actual testing being done.

Describe your test in detail and include relevant config.
 
Alright -- I must be doing something completely wrong with this Cisco config. After 30+ configs of new and used ciscos could it be that I am forgetting the basics?

My situation is slightly changed from the earlier description.

I have two new (used) cisco WS-2950G-24-EI switches running the latest firmware c2950-i6q4l2-mz.121-22.EA13.

The switches are connected through Fa0/1 on each by a crossover cable. The lights are green. The ports are set to Trunk / all, auto auto.

I have specified Vlan2 as management on each switch and assigned IPs on the same subnet to each.

I am connected to the switches using the console cable.

These switches are just not talking to each other. I am at a loss as to the cause. To simplify troubleshooting -- the ciscos should be exchanging CDP info via that pair of trunk ports. Both ciscos show outgoing CDP and no incoming traffic. There is no IP connectivity here either, one switch cannot ping the IP of the other.

These are used switches but the hardware seems to be fine. Help me see otherwise if that's the case. Have tried multiple ports, vlans and patch cables with the same results. Also disabled CDP v2 advertisements as a test.

Any thoughts?

Here are the configs from each switch, lanex1 and lanex2.

lanex1#sh conf

Using 1436 out of 32768 bytes

!

version 12.1

no service pad

service timestamps debug uptime

service timestamps log uptime

no service password-encryption

!

hostname lanex1

!

enable secret 5 $1$8LZi$FBwZGfhDJrkWaKefc3e8q/

enable password thepass

!

ip subnet-zero

!

!

spanning-tree mode pvst

no spanning-tree optimize bpdu transmission

spanning-tree extend system-id

!

!

!

!

interface FastEthernet0/1

switchport mode trunk

!

interface FastEthernet0/2

!

interface FastEthernet0/3

!

interface FastEthernet0/4

!

interface FastEthernet0/5

!

interface FastEthernet0/6

!

interface FastEthernet0/7

!

interface FastEthernet0/8

!

interface FastEthernet0/9

!

interface FastEthernet0/10

!

interface FastEthernet0/11

!

interface FastEthernet0/12

!

interface FastEthernet0/13

!

interface FastEthernet0/14

!

interface FastEthernet0/15

!

interface FastEthernet0/16

!

interface FastEthernet0/17

!

interface FastEthernet0/18

!

interface FastEthernet0/19

!

interface FastEthernet0/20

!

interface FastEthernet0/21

!

interface FastEthernet0/22

!

interface FastEthernet0/23

!

interface FastEthernet0/24

!

interface GigabitEthernet0/1

!

interface GigabitEthernet0/2

!

interface Vlan1

no ip address

no ip route-cache

shutdown

!

interface Vlan2

description management

ip address 172.16.180.1 255.255.0.0

no ip route-cache

!

ip default-gateway 172.16.1.1

ip http server

no cdp advertise-v2

!

line con 0

line vty 0 4

password route2

login

line vty 5 15

password route2

login

!

!

end

--------------------------------------------

lanex2#show conf

Using 1412 out of 32768 bytes

!

version 12.1

no service pad

service timestamps debug uptime

service timestamps log uptime

no service password-encryption

!

hostname lanex2

!

enable secret 5 $1$Q/QE$jEw7FKA3q47KgkuyrZo0B/

enable password thepass

!

ip subnet-zero

!

!

spanning-tree mode pvst

no spanning-tree optimize bpdu transmission

spanning-tree extend system-id

!

!

!

!

interface FastEthernet0/1

switchport mode trunk

!

interface FastEthernet0/2

!

interface FastEthernet0/3

!

interface FastEthernet0/4

!

interface FastEthernet0/5

!

interface FastEthernet0/6

!

interface FastEthernet0/7

!

interface FastEthernet0/8

!

interface FastEthernet0/9

!

interface FastEthernet0/10

!

interface FastEthernet0/11

!

interface FastEthernet0/12

!

interface FastEthernet0/13

!

interface FastEthernet0/14

!

interface FastEthernet0/15

!

interface FastEthernet0/16

!

interface FastEthernet0/17

!

interface FastEthernet0/18

!

interface FastEthernet0/19

!

interface FastEthernet0/20

!

interface FastEthernet0/21

!

interface FastEthernet0/22

!

interface FastEthernet0/23

!

interface FastEthernet0/24

!

interface GigabitEthernet0/1

!

interface GigabitEthernet0/2

!

interface Vlan1

no ip address

no ip route-cache

shutdown

!

interface Vlan2

ip address 172.16.180.2 255.255.0.0

no ip route-cache

!

ip default-gateway 172.16.1.1

ip http server

no cdp advertise-v2

!

line con 0

line vty 0 4

password route2

login

line vty 5 15

password route2

login

!

!

end
----------------------------------------------

Thinking it may be a problem with me not seeing a required configuration item that is due to the new firmware, I am downgrading these switches to older firmware now. Any other suggestions welcome.


Thank You
 
how are is your vlan traffic going to get to the default gateway?

interface Vlan2

description management

ip address 172.16.180.1 255.255.0.0

no ip route-cache

!

ip default-gateway 172.16.1.1
 
172.16.180.1 is on a different network that 172.16.1.1 how does one subnet route to the other? 172.16.1.1 is your next hop correct? can a device in vlan 2 ping the gateway?
 
The 172.16.1.1 is not assigned to any physical interface on this network yes, however, the ping test was directed from 172.16.180.1 to 172.16.180.2 and vice-versa.

In my 30+ switch network, I have specified no default gateway and they are sharing, pingable and etc. with no issue.

Thanks
 
can you post the output from sh int f0/1 switchport from both switches?? north, it's a /16 mask so the .1.1 address is in the same subnet

I hate all Uppercase... I don't want my groups to seem angry at me all the time! =)
- ColdFlame (vbscript forum)
 
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