Allied Telesis AT-9448Ts/XP (Basic Layer 3) - Manual (Page 37)

AT-9400 Series Gigabit Ethernet Switches Installation Guide
37
Expansion Slot
The expansion slot on the AT-9424Ts, AT-9424Ts/XP, and AT-9448Ts/XP
Switches accommodates the optional AT-StackXG Stacking Module. The
module is used to create stacks of up to five or eight switches, depending
on the model. The switches of a stack function as a single, logical unit in
which the network functions, such as the spanning tree protocol and static
port trunks, span across all the ports, increasing network bandwidth and
simplifying network management.
For further information and installation instructions, refer to the AT-9400
Stack Installation Guide.
Note
Do not install the AT-StackXG Stacking Module into a switch until
you have read the Software Release Notes included with the latest
release of the AT-S63 Management Software. This module may not
be appropriate for all network environments because stacks do not
support all the features of the AT-S63 Management Software.