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VLAN issues between a SA520 and an SG 300

I have an SA520 with firmware 2.1.72   it is generating a VLAN on port 1  with 192.168.75.x   DHCP enabled

a second vlan on port 2  with 10.40.1.x  no DHCP

I have an SG300  with firmware

With  a VLAN on ports 1-16  that will have the 192.168.75.x  network and  a VLAN with ports 17-24

that will have the 10.40.1.x  network .

If I plug in port 1 in the SA 520 to port 1 on the  SG300 it works great


If I plug in port 2 in the SA 520 to port 17 on the SG300 it works great

but if I plug in both at the same time. the SG 300 wigs out and will not route for anyone.

is there a setting on either the SA 520 or the SG 300 that will let me  work with this setup?

Everyone's tags (7)
New Member

VLAN issues between a SA520 and an SG 300

More information

ports 1 and 17 on the SG300 are trunk

all other ports are general  untagged

vlan 1 has all ports in vlan 2 as excluded 

vlan 2 has all ports in vlan 1 as excluded


VLAN issues between a SA520 and an SG 300

Hello David, the spanning-tree function is likely trashing out the SA500. Assuming the spanning-tree is operating on the SG 300 switch, one of the ports should get shut down as soon as it detects the redundant link on the same vlan.

If the SA500 is locking up or "wigging out" it sounds like the STP is disabled on the Sg 300 and it is broadcast looping, likely consuming all the SA500 memory and making it crash.

-Tom Please mark answered for helpful posts
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