Dell Force10 S50N Uplink Configuration Question

Hi Guys,

I'm wondering - I have a Dell Force10 (S50N) which I'm using as a core colo switch on an L2 network (I'm being routed to).

However, while I can access the switch just fine via in-band methods (SSH, etc.) - I cannot see any of the devices behind the switch.

This is what I have for the uplink port:

interface GigabitEthernet 0/48
description Uplink to Tierpoint - IP+
ip address 174.136.47.2/24
mtu 9252
no shutdown

Here's one of the affected downline hosts:

interface GigabitEthernet 0/1
description XEN1-0.DFW1
no ip address
switchport
no shutdown

I cannot see their ARP on the switch, etc. - they're completely offline.

As such - I was wondering if there was anything that I'm missing in order to make this work. However, I note the following - which may be the issue:

CORE-SW1.DFW1#show interfaces vlan 1
Vlan 1 is down, line protocol is down
Address is 00:01:e8:d6:06:df, Current address is 00:01:e8:d6:06:df
Interface index is 1107787777
Internet address is not set
MTU 1554 bytes, IP MTU 1500 bytes
LineSpeed 100 Mbit
ARP type: ARPA, ARP Timeout 04:00:00
Last clearing of "show interface" counters 03:34:13
Queueing strategy: fifo
Time since last interface status change: 03:34:13

Though - I'm not sure what I need to do in terms of bringing that up since I do not have any more IP's to assign.

Any clues or next steps I should be looking at?