SG300 VLANs with multiple trunk ports

[Robert899]

I currently have a 10 port SG300 and a Ubiquiti EdgeRouter. I have 2 VLANs established with one port on the SG300 configured as a trunk and connected to the router. Traffic from both VLANs get passed to the router/firewall. All is working well.

I am thinking of upgrading to a 24 port SG300 with PoE. My question concerns using two (or more) trunk ports on the SG300 connected to the router and whether it is a recommended practice.

For example, lets say I have VLANs 3,4,5 as well as 6,7,8 defined. I could expand my current setup and use a single trunk port on the SG300 to pass traffic to the router. Or I could configure two SG300 trunk ports, one for VLANs 3,4,5 and another for 6,7,8. Each trunk port is connected to separate ports on the router (assume each router port is correctly setup to handle intended VLAN traffic).

With the one trunk port solution, I would worry about traffic congestion on the trunk link. With the two trunk port solution, I can distribute traffic and utilize some of the spare capacity on my router/firewall. Is my thinking correct on this, or am I asking for trouble?

[Seb Rupik · Accepted solution]

Hi there,

While your idea would work, if you have the spare interfaces on both the firewall and SG300 then you should build some resilience into your network.

Instead of taking two links carrying disparate traffic to and fro the firewall, create an LACP etherchanel (LAG) and bundle the links together. If you are worried about congestion should one link fail, the SG300 supports up to eight interfaces in one LAG.

cheers,

Seb.

[Robert899]

Thank you very much for that information. I will go and investigate LAGs.