Options for configuring a commander and candidates

Depending on how Commander and Candidate switches are configured, Candidates can join a stack either automatically or by a Commander manually adding (pulling) them into the stack. In the default configuration, a Candidate joins only when manually pulled by a Commander, but you can reconfigure a Commander to automatically pull in Candidates that are in the default stacking configuration. Also a Candidate switch can be re-configured to either "push" itself into a particular Commander's stack, convert the Candidate to a Commander (for a stack that does not already have a Commander), or to operate as a standalone switch without stacking. The following table shows your control options for adding Members to a stack.

Stacking configuration guidelines

Join Method 1

Commander (IP Addressing Required)Auto Grab

Candidate (IP Addressing Optional)Auto Join

Passwords

Automatically add Candidate to Stack Causes the first 15 eligible, discovered switches in the subnet to automatically join a stack.

Yes

Yes (default)

No (default)

Manually add Candidate to StackPrevent automatic joining of switches you don't want in the stack

No (default)

Yes (default)

Optional1

Yes

No

Optional1

Yes

Yes (default) or No

Configured

Prevent a switch from being a Candidate

N/A

Disabled

Optional

1

The Commander's Manager and Operator passwords propagate to the candidate when it joins the stack.

The easiest way to automatically create a stack is to:

Procedure
  1. Configure a switch as a Commander.
  2. Configure IP addressing and a stack name on the Commander.
  3. Set the Commander's Auto Grab parameter to Yes.
  4. Connect Candidate switches (in their factory default configuration) to the network.

This approach automatically creates a stack of up to 16 switches (including the Commander). However this replaces manual control with an automatic process that may bring switches into the stack that you did not intend to include. With the Commander's Auto Grab parameter set to Yes, any switch conforming to all four of the following factors automatically becomes a stack Member:
  • Default stacking configuration (Stack State set to Candidate, and Auto Join set to Yes)

  • Same subnet (broadcast domain) and default VLAN as the Commander (If VLANs are used in the stack environment, see "Stacking Operation with Multiple VLANs Configured” on page Stacking operation with multiple VLANs configured.)

  • No Manager password

  • 14 or fewer stack members at the moment