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Can't ping/telnet/ssh to/from management after switching to SFP modules (Screwed something up or a bug?)

misullivan
Level 1
Level 1

Ok experts got a good one for you...

Simple hub+spoke setup.  All C3750s.. a C3750G-TS a C3750-PS and a C3750-WS (with wireless controller).  The C3750G-TS is the hub to the outside world.  All have c3750-ipbasek9-mz.150-2.SE11 on them.

 

Configs are here:

C3750G-TS -> https://dpaste.de/vzUn/raw
C3750-PS -> https://dpaste.de/Kots/raw

C3750-WS -> https://dpaste.de/CWsv/raw

 

Have a desktop (Mac) plugged into the TS - Gi2/0/2 has both vlans 10 and 100 configured - vlan 10 is the important one at the moment..
Have various other devices plugged into the PS - Gi2/01 thru 12 the Mac can talk to them no problem at all (ie the trunk over the SFP has to be working)

Firewall (non cisco) is not VLAN aware and is connected to the TS - Gi2/0/1 for Vlan 10 and Gi2/0/3 for Vlan 2.

Now the problem...

From the Mac (Vlan 10), I can ping/telnet/ssh/http the TS and the WS on 172.17.2.39 and 172.17.2.37 respectively (Vlan 2).  I cannot however get to the PS on 172.17.2.38.

Similarly from the TS I can ping itself (no surprises there) the default gateway (firewall) on 172.17.2.254 and the WS 172.17.2.37.  On the WS is can ping itself, the default gateway (172.17.2.254) and the TS on 172.17.2.39.  Neither the TS nor the WS can ping the PS on 172.17.2.38.

The PS cannot ping anything except itself on 172.17.2.38 (not the TS, the WS nor the firewall on 172.17.2.254.)

..... lastly .....

 

It was all working using the WS as the hub and copper connections earlier today with pretty much the same config...

These are the interfaces (sh int <etc> for each of the SFP ports - hostnames tell you which is the hub): https://dpaste.de/74MR/raw

Thanks in advance for any insight on whether I am truly a moron or have stumbled on something odd..

 

Regards,

 

Michelle

1 Accepted Solution

Accepted Solutions

Ok thanks for the reply however...


@paul driver wrote:


The Ts switch should be providing the L3 routing as such the other two switches need only need to have the mgt vlan configured ( in your case it looks like vlan 2) all other l3 interfaces are NOT necessary.

 


Don't want this - want the management vlan to be 2, and want it all at the L2 layer as there is L3 routing and AAA upstream.

 



Also you are tagging the native vlan on the TS switch ( vlan dot1q tag native ) but not on the other two switchs even though they have interconnected to the TS switch.

Sure about that? All were showing it in the config (and it was a default item).

 

However this is the answer... the PS switch didn't have 'vlan dot1q tag native' and as soon as I added it everything started working correctly.

 

Regards,

 

Michelle

 

 

View solution in original post

3 Replies 3

Hello

The Ts switch should be providing the L3 routing as such the other two switches need only need to have the mgt vlan configured ( in your case it looks like vlan 2) all other l3 interfaces are NOT necessary.

Also you are tagging the native vlan on the TS switch ( vlan dot1q tag native ) but not on the other two switchs even though they have interconnected to the TS switch.

 

Vtp is transparent on PS/WS switchs and have differing L2 vlans, with TS switch showing no L2 vlans configured

lasty you have ssh applied to the vty lines but ssh ISNT enabled on the switches.

Suggest:
TS switch
conf t
interface Vlan1
ip address 10.0.0.198 255.255.255.0

no vlan dot1q tag native 
ip routing
ip route 0.0.0.0 0.0.0.0 172.17.2.254

line vty 0 4
transport input telnet

privilege level 15



PS/WS switch
conf t
ip default-gateway 172.17.2.39
no ip routing
no int vlan 100

interface Vlan1
no ip address

line vty 0 4
transport input telnet

privilege level 15

 

All switches
Have the correct vlans that need to travese the trunks applied to each switch

res
Paul

 


Please rate and mark as an accepted solution if you have found any of the information provided useful.
This then could assist others on these forums to find a valuable answer and broadens the community’s global network.

Kind Regards
Paul

Ok thanks for the reply however...


@paul driver wrote:


The Ts switch should be providing the L3 routing as such the other two switches need only need to have the mgt vlan configured ( in your case it looks like vlan 2) all other l3 interfaces are NOT necessary.

 


Don't want this - want the management vlan to be 2, and want it all at the L2 layer as there is L3 routing and AAA upstream.

 



Also you are tagging the native vlan on the TS switch ( vlan dot1q tag native ) but not on the other two switchs even though they have interconnected to the TS switch.

Sure about that? All were showing it in the config (and it was a default item).

 

However this is the answer... the PS switch didn't have 'vlan dot1q tag native' and as soon as I added it everything started working correctly.

 

Regards,

 

Michelle

 

 

...and just so you know - you pointed out the missing setting ... I had missed that it wasn't on all three switches - seems the upgrade to 15.x had removed it (because it was there before.)

Thanks anyway... seems I was the moron after all :)
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