Notes On Stacking Switches - D-Link DES-3326SR Manual

Notes on Stacking Switches

By default, the Switch configuration settings allow it to operate as a standalone device, or in a stacked group. It
is not necessary to change any settings for the Switch to function in either capacity. However, it is recommended
that a Master Switch be manually designated for a stacked group when it is first set up.
Keep in mind the following guidelines when setting up a Switch stack:
•
A Switch that is not connected to another DES-3326SR through the stacking ports will operate as a
standalone Switch even if the stacking mode is enabled as a Master or in Auto mode.
•
In order to easily identify the Master Switch, place the designated Master unit at the top of the stack.
Use the auto stacking mode for the remaining Switches. Stack order is determined by how the Switches
are connected in relation to the Master.
•
If a link between stacked switches fails the stacked group must be connected to work around the failed
link. As with any changes in the composition of the stacked switch group, the new stacking relationship
must be negotiated. Any change to the composition of a stacked switch group or any failure of a
stacking port will cause the entire stack to restart and negotiate the new stacking composition.
The slave Switch units must meet the following criteria:
•
All additional slave Switches must be the same model, that is (at the time of the writing of this manual),
the slaves must be all DES-3326SR Switches. The slave unit types cannot be mixed within a single
stacked group.
•
All Switches must have the same firmware version loaded to operate in a stacked group.
•
A Master should be designated for the group. If the remaining Switches are using the default stacking
mode configuration, the Master will be recognized and the stack order established automatically.
Stacking mode can be changed using the CLI. The possible stacking configuration modes are as follows:
Disabled: This forces the Switch to operate as a standalone device. In standalone mode the Switch functions as a
standalone device even if a stacking module is installed. To force standalone operation it is necessary to use the
CLI command config stacking mode disable. A Switch that has stacking mode disabled should
never connect to another Switch through stacking ports. See below for notes on standalone operation.
NOTICE: Do not use stacking ports on a Switch that has the stacking mode disabled.
Enabled: Stacking mode is enabled by default. When enabled the Switch can operate as a standalone device or it
can operate with other DES-3326SR Switches in a properly connected stacked group. Stacking must be enabled
for the Switch function in a stacked arrangement with other DES-3326SR Switches. When stacking mode is
enabled it must also be configured to function in auto, master or slave mode.
Auto: This is the default stacking mode setting for the DES-3326SR. In auto stacking mode the Switch is
eligible for stacking or it can operate as a standalone device. If a DES-3326SR Switch stack is connected and all
units are configured to operate in auto stacking mode, the master-slave relationships is determined automatically.
However, as previously noted, it is better to manually designate a Switch (at the top of the stack) to be the
Master Switch and restart the entire stack. See the instructions below for details on how to manually designate a
Master.
Master: The auto mode described above may be overridden so that a properly connected Switch in a stack may
be forced into master mode. Only one Switch in a stack may act as the master and all configuration settings for
the stacked group - including stacking configuration - are saved in configuration files in the master Switch. The
stack is managed as a single entity through the master. It may be convenient to place the master unit in the
upper-most slot of a stacked group to visually distinguish it form the slave units. The master unit should be used
to uplink the stack group to the backbone. If the master unit fails or is replaced for any reason, it is possible to
load configuration files saved from the original master unit in order to continue operation with identical settings.
Slave: The auto mode may be overridden to force the Switch to operate in slave mode. When the Switch is in
slave mode, it is ineligible to function as a master and all configuration, is done through the Master unit. A
Master Switch must be properly connected to the stack for a Switch to operate in slave mode.
D-Link DES-3326SR Layer 3 Switch
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