We are new to VLANs and just have a basic question to clear up some issues with understanding a few points
We have a 3com 5500G backbone consisting of 1 copper 48 port 5500G and 1 x Fibre 5500G linked together by XRN. The copper switch acts as a server switch and the fibre switch ports each has a 3Com 2948 switch attached to them. 2 fibre ports are inter site links running at 10mb and 100mb to different sites.
What I want to do is VLAN off segments of the network possibly switch rooms at a time which could be a group of 4 x 2948. But also vlan off each inter site link.
What I have been doing as a test is the following
VLAN1 - Servers and Admin
VLAN2 - Site 1
VLAN3 - Site 2
VLAN4 - Switch room 1
As the 5500G is a layer 4 switch it can handle the routing and has allowed me to create a vlan interface for each vlan which works well.
What I have done is rather than go into the end point switches is set each fibre port on the 5500G to a VLAN(untagged)
e.g. 1/0/1 VLAN2 1/0/2 VLAN3 etc
Each VLAN correctly DHCP's to its own subnet(from a single DHCP). My first question is should it be possible that each VLAN can ping and access each other? (Because they do). I was expecting them not being able to without being specifically tagged with the others vlan id?
My second question is if this is supposed to happen like this then is it reducing the broadcasts like VLANs should? vs a flat network
Number 3 is if I havent done things right should we be going into the 2948's and setting the VLANs there rather than at the core?(We were being lazy because we didnt see it was necessary)
Sorry for the essay hope I've explained myself