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New Member

SG300-28 poor performance other than native vlan.

We have a single SG300-28 in L2 mode with

3 vlans

3 virtual interfaces and 1 parent interface configured on the sonic firewall

Switch(trunk allow all)-->sonic( 1 parent interface and 3 virtual IP's)

vlan 10

vlan 20

vlan 30

vlan 1 (parent interface)

Cisco switch mgmt IP

When PC connected to access port of switch with pvid ( 10 or 20 or 30) performance to internet is slow.

When PC connected to access port of switch with pvid ( 1) performance is as expected.

PC is able to connect to firewall and get DHCP configuration automatically based on the port which vlan is configured.

We connected PC directtly to firewall and performance is good irrespective whcih vlan tag was set by PC using realtek utilitiy. Based on the tag set

PC automatically got DHCP IP for that vlan from firewall. This tells us that the performance problem is isolated to Switch.

Please advise what could be done.

I will update to 1.1.2 and test out. So far this switch has been  PITA.

New Member

Re: SG300-28 poor performance other than native vlan.

Hi Dave,

                As per your email I did  within switchperformance for clients in vlan 10 and also native vlan. There is no perfromance difference.

As per setup couple of ports in access vlan 10,20,30 etc and rest in native. Port 24 which is trunked to allow all vlan is connected to Sonic FW. Please see attached ttcp results and show tech.

When I say performance to WAN is poor through firewall it means that webpage from is slow and other webistes like gmail load very slowly (almost unusable)

Thank you,


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