Yes they can.  You will need a trunk set on the ports connecting the physical switches together.  The VLANs will communicate at Layer 2 of the OSI model.   This overview should help with defining what a "stacked" switch is: Stacking Overview PowerConnect 3524/P and PowerConnect 3548/P stacking provides multiple switch management through a single point as if all stack members are a single unit. All stack members are accessed through a single IP address through which the stack is managed.  The stack is managed from a: • Web-based interface • SNMP Management Station • Command Line Interface (CLI) PowerConnect 3524/P and PowerConnect 3548/P devices support stacking up to eight units per stack, or can operate as stand-alone units. During the Stacking setup, one switch is selected as the Stack Master and another stacking member can be selected as the Backup Master. All other devices are selected as stack members, and assigned a unique Unit ID. Switch software is downloaded separately for each stack members. However, all units in the stack must be running the same software version. Switch stacking and configuration is maintained by the Stack Master. The Stack Master detects and reconfigures the ports with minimal operational impact in the event of: • Unit Failure • Inter-unit Stacking Link Failure • Unit Insertion • Removal of a Stacking Unit
I have a small network with about 200 network devices,20 users and 10 printers. The network is spreed out over a large building. I have central networking rack with about 150 ports and three remote closets connect by fiber with switches to attach to device in the area. The switches where setup back in 2000 when the number of networked devices was half of what it is now.  The switches are getting old and need replaced. The switches are also not stacked properly. They are stack by interconnecting the switches through the regular ports. This may have been fine back in the day but with the network growth we seen it needs to be better.  I am not really interested in gigabit ethernet, 10/100M is fine. I am looking at the Powerconnect 3500 or 5500 series switches. I am also looking to stack them correctly and setting up VLANs for performance and security.  Does any one have any suggestions or recommendations? Can you span switches with VLANs?
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