4

I have several switches (some on same floor and another on other floors) all connected to core layer 3 switches through trunk links.

One of the vlan id / name is repeated along the switches. May I use the same network subnet for that repeated vlan id / name?

I would think so, because I can only have one default gateway per vlan once I implement inter-vlan on those layer 3 switches.

Improve this question
1
  • Did any answer help you? if so, you should accept the answer so that the question doesn't keep popping up forever, looking for an answer. Alternatively, you could post and accept your own answer.
    – Ron Maupin ♦
    Commented Jan 6, 2021 at 0:25

1 Answer 1

Reset to default
5

Remember that layer-3 switches are still layer-2 switches. The layer-3 interfaces are SVIs (virtual interfaces, internal to the layer-3 switch), and you connect your layer-2 access switches to the layer-3 distribution switch via a layer-2 trunk, and all the layer-2 access switches could have the same VLAN(s).

A VLAN can be assigned to multiple layer-2 interfaces (including trunk interfaces) on the layer-3 switch. The layer-3 routing happens between the SVIs inside the layer-3 switch. The layer-3 address assigned to an SVI for a VLAN is the gateway address of the hosts on that VLAN.

Improve this answer
1
  • Ok thanks, so I will need to use the same network subnet for the repeated vlan id / name since I can only assign one svi per vlan to be the default gateway for each of those vlans on the layer 3 switch.
    – Novice Programmer
    Commented May 22, 2019 at 13:58

Not the answer you're looking for? Browse other questions tagged or ask your own question.