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VLans and SFP; 2 switches connected together on both SFP Ports

I am trying to quote a network and need to figure out how many switches I need. What I am trying to figure out is can I connect  2 Unifi switches together over fiber more than once? Not sure how to describe what I am trying to do but here it goes. I want to connect Switch A SFP 1 to Switch B SFP 1 on VLan 10, with ports 1-14 VLan 10. And then Connect Switch A SFP 2 to Switch B SFP 2 VLan 20 with ports 15 & 16 assigned to VLan 20. Is this possible with Unifi?

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Re: VLans and SFP; 2 switches connected together on both SFP Ports

Probably, although spanning tree may block one link unless disabled, and you would need untagged managment traffic enabled on one of the links so the controller can communicate with the remote switch.

 

The more usual way of increasing the bandwidth between switches would be to create a link aggregeation group (LAG) https://help.ubnt.com/hc/en-us/articles/360007279753-UniFi-USW-Configuring-Link-Aggregation-Groups-L... an transporting the multiple VLANs over the one LAG.

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Re: VLans and SFP; 2 switches connected together on both SFP Ports

I'm not trying to increase bandwidth. I'm trying to connect 2 switches on a CCTV network over a separate fiber pair to reduce the traffic on SFP 1 which will be used for the hotel WiFi.

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Re: VLans and SFP; 2 switches connected together on both SFP Ports

You are likely better served with a “trunk” connection with both VLANs running over it. If bandwidth is a concern, then as @tomw said, run a second connection and put them together in a LAG group. This is sufficient for the 2 switch scenario you describe.

If you want to connect the same switches with separate links for each VLAN, you would need “Per VLAN STP” (PVST) which isn’t available in Unifi switches. This is only useful if you have 3 or more switches with redundant links and wish to spread the trunked traffic around to avoid “dark links”.
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Re: VLans and SFP; 2 switches connected together on both SFP Ports

Looks like we posted at the same time.

The second link is going to be blocked by STP as a “loop”.

Sounds like you are trying to use the second link as a “poor man’s QoS” limiter to keep camera traffic from spamming the main VLAN.

Without PVST, you’re likely to have to make the trunk fat enough to absorb both networks worth of traffic or introduce switch C to take the VLAN20 from switch A.
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Re: VLans and SFP; 2 switches connected together on both SFP Ports

I still dont think I have described what I am trying to accomplish. I'm not at my desk so it isnt pretty but this might help. I know I can do this with other switches, just not sure if the controller will assign the Trunk port and route accordingly.

 

          Screenshot 2018-11-04 15.05.44.png

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Re: VLans and SFP; 2 switches connected together on both SFP Ports

Mantra: USG is NOT a switch...

The USG isn’t the “root switch”, it is more like another peripheral like a computer. The management VLAN doesn’t go out the second LAN port, you’ll have trouble adopting Switch B.

Not too different would be to plug both LAN ports of the USG into THE SAME SWITCH (Switch A). You can bind VLAN20 to the second port.

Then run a trunk line from Switch A to B that carries both VLANs.

It may sound like you’d create a switching loop by plugging both LAN ports of the USG to the same switch. But...

Mantra: USG is NOT a SWITCH
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Re: VLans and SFP; 2 switches connected together on both SFP Ports

Yes I fully understand its not a switch. The title of this post was just to catch attention. I just wanted to know if the controller was capable of setting up two different networks on the switch. Most managed switches are capable. But all I can get is answers as to why my description is wrong.. 

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Re: VLans and SFP; 2 switches connected together on both SFP Ports

Yes. The entire Unifi line supports VLANs.