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Appears to be a VLAN Issue

Duldul123
Level 1
Level 1

Why does on a 2950 switch when a second VLAN is created, it puts VLAN 1 down. When VLAN 1 is brought up then VLAN 2 comes down?

Same problem occurs on a second 2950 switch.

Any comments on why it is behaving like this and how can VLAN 1 and VLAN 2 can both be in up state would be appreciated.

2 Accepted Solutions

Accepted Solutions

Edison Ortiz
Hall of Fame
Hall of Fame

Catalyst 2950 is a Layer2 switch and by design is only able to have one management Vlan (layer3 interface) up at the same time.

Having multiple Layer3 interfaces up at the same time would imply the switch can route between Vlans which by hardware constraints is unable to do.

HTH,

__

Edison.

View solution in original post

glen.grant
VIP Alumni
VIP Alumni

As Edison points out the ip address is to manage the switch via telnet or ssh and nothing else , it cannot route between different vlans so you only need one SVI up at any given time , a layer 3 device such as a router or a l2/l3 switch is needed to accomplish that function.

View solution in original post

2 Replies 2

Edison Ortiz
Hall of Fame
Hall of Fame

Catalyst 2950 is a Layer2 switch and by design is only able to have one management Vlan (layer3 interface) up at the same time.

Having multiple Layer3 interfaces up at the same time would imply the switch can route between Vlans which by hardware constraints is unable to do.

HTH,

__

Edison.

glen.grant
VIP Alumni
VIP Alumni

As Edison points out the ip address is to manage the switch via telnet or ssh and nothing else , it cannot route between different vlans so you only need one SVI up at any given time , a layer 3 device such as a router or a l2/l3 switch is needed to accomplish that function.

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