Configuring stack management

This process assumes that:

  • All switches to include in a stack are connected to the same subnet (broadcast domain).

  • If VLANs are enabled on the switches to include in the stack, then the ports linking the stacked switches must be on the primary VLAN in each switch. If the primary VLAN is tagged, then each switch in the stack must use the same VLAN ID (VID) for the primary VLAN.

  • If you are including an HP Switch 8000M, 4000M, 2424M, 2400M, or 1600M in a stack, you must first update all such devices to software versionC.08.03 or later. Copies of the latest software version are available from the HP Switch Networking web site or can be copied from one switch to another. For downloading instructions, see the Basic Operations Guide for your switch.

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 reconfigured 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)[a]

Manually add Candidate to Stack

Prevent automatic joining of switches you don't want in the stack

No (default) Yes (default) Optional[a]
Yes No Optional[a]
Yes Yes (default) or No Configured
Prevent a switch from being a Candidate N/A Disabled Optional

[a] 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:

  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).

  • No Manager password

  • 14 or fewer stack members at the moment