3Com Switch 4500 Family Manual page 152

Assigning or removing an aggregation member port to or from the isolation group can cause the
other ports in the aggregation group join or leave the isolation group.
For ports that belong to an aggregation group and an isolation group simultaneously, removing a
port from the aggregation group has no effect on the other ports. That is, the rest ports remain in
the aggregation group and the isolation group.
Ports that belong to an aggregation group and the isolation group simultaneously are still isolated
after they are removed from the aggregation group (in system view).
Assigning an isolated port to an aggregation group causes all the ports in the aggregation group on
the local unit to join the isolation group.
The Switch 4500 family support cross-device port isolation if XRN fabric is enabled.
By default, the isolation group contains no port.
Examples
# Assign Ethernet 1/0/1 and Ethernet 1/0/2 to the isolation group.
<Sysname> system-view
System View: return to User View with Ctrl+Z.
[Sysname] interface ethernet1/0/1
[Sysname-Ethernet1/0/1] port isolate
[Sysname-Ethernet1/0/1] quit
[Sysname] interface ethernet1/0/2
[Sysname-Ethernet1/0/2] port isolate
After the configuration, packets cannot be exchanged between Ethernet 1/0/1 and Ethernet 1/0/2.
# Remove Ethernet 1/0/1 from the isolation group.
[Sysname-Ethernet1/0/1] undo port isolate
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