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I am trying to set up a connection between 2 buildings. In building 1 I have the following:

  1. Network 1
  2. Network 2
  3. Network 3
  4. Network 4

All the above are just different subnets on different cables. Let's say I run one cable to building 2. I have a Cisco SG300-10 in each building and I would like to plug all 4 into the first switch, and by creating port based VLANs trunk them together, connect the 2 switches with the cable that runs across the 2 buildings and patch in in building 2.

I have created 4 VLANs using the web interface. In the port VLAN membership of each switch I have

GE1 Trunk 1UP 1UP
GE2 Access 2UP 2UP
GE3 Access 3UP 3UP
GE4 Access 180UP 180UP
GE5 Access 10UP 10UP
GE6 Trunk 1UP 1UP
GE7 Trunk 1UP 1UP
GE8 Trunk 1UP 1UP
GE9 Trunk 1UP 1UP
GE10 Trunk 1UP, 2T, 3T, 10T, 180T 1UP, 2T, 3T, 10T, 180T

The cable that runs between the 2 buildings is on port 10 on each switch. I plug all the cables in building 1 and then when I go to building 2, I dont get an IP on port 2,3,4 or 5. But if I connect a cable on port 1 and on port 10 on each switch, then I get an IP in building 2. Can anyone tell me what I am missing? I had the same setup some years ago with Netgear switches and it was working fine.


share|improve this question
In building 1, what are ports 2-5 on teh SG300 connected to physically? If you unplug the cable that's going into GE2 on the SG300 and plug it into your laptop, do you get an IP? – Paul Ackerman Aug 16 '12 at 15:31
Yes, I get an IP. GE2 is plugged in to a switch on the network and that cable gives me an IP in that range – Nic Aug 16 '12 at 15:55
It's gotta be something silly - this should work. On other cisco switches, you must create the vlan on each switch or use VTP. Have vlans 2, 3, 10 and 180 been created on both switches? I know they're being passed by the trunk ports but they need to exist on the switches themselves also. – Paul Ackerman Aug 16 '12 at 16:03
both vlans have been created on both switches. They are exactly the same. – Nic Aug 17 '12 at 15:59

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