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processing power, interaction, unified management, and uninterrupted maintenance of multiple
devices.
A stack provides a single point of management. You can access the stack from any member device
to configure and manage all the members as if they were interface modules on one node. Settings
will be issued to all member devices in the stack.
The following information describes the concepts that you might encounter when you use stacking.
NOTE:
Stacking and stack are called IRF on the webpages and in online help.
Stack member roles
HPE OfficeConnect 1950 stacking uses two member roles: master and standby (also called
subordinate).
When devices form a stack, they elect a master to manage and control the stack. All the other
members process services while backing up the master. When the master device fails, the other
devices automatically elect a new master.
Stack port
A stack port is a logical interface for the connection between stack member devices. Every stackable
device supports two stack ports. The stack ports are referred to as IRF-port 1 and IRF-port 2.
To use a stack port, you must bind a minimum of one physical interface to it. The physical interfaces
assigned to a stack port automatically form an aggregate stack link.
When you connect two neighboring stack members, connect the physical interfaces of IRF-port 1 on
one member to the physical interfaces of IRF-port 2 on the other.
Stack physical interfaces
Stack physical interfaces connect stack member devices and must be bound to a stack port. They
forward stack protocol packets and data packets between stack member devices.
You can use 10GBase-T or SFP+ ports for stack links.
To connect the 10GBase-T Ethernet ports in a short distance, you can use Category 6A (or above)
twisted-pair cables.
To connect the SFP+ ports in a short distance, you can use SFP+ DAC cables.
To connect the SFP+ ports in a long distance, you must use SFP+ transceiver modules and fibers.
You can assign fiber and copper ports to the same stack port. However, the ports at the two ends of
a stack link must be the same type.
Stack domain ID
One stack forms one stack domain. Stack domain IDs uniquely identify stacks and prevents stacks
from interfering with one another.
Stack split and stack merge
A stack split occurs when a virtual stack breaks up into two or more virtual stacks because of stack
link failures.
