Troubleshooting maximum stack members exceeded

Cause

This failure can happen if you have an active stack that has already reached its maximum number of members. It can also happen when the maximum number of switches is reached with a combination of active members and strictly provisioned members.

Since one of the suggested initial deployment techniques is a deterministic method using strictly provisioned entries, this failure example demonstrates what occurs if the maximum number of members is reached by strictly provisioning four members. At least one of these configuration entries has an incorrect MAC address. Similar to the mismatched MAC address example, the stack attempts to “plug-and-go” to add the switch, however, since the maximum number of members has already been reached, the switch cannot join the stack.

Action
  1. The following example shows the show stacking output before the switch attempts to join.

    Displaying stack members before the join

    switch(config)# show stacking
    
    Stack ID         : 00031cc1-de4d87c0
    MAC Address      : 1cc1de-4dc765
    Stack Topology   : Ring
    Stack Status     : Active
    Uptime           : 0d 1h 27m
    Software Version : WB.15.11.0000x
    
    Mbr
    ID  Mac Address   Model                                  Pri Status
    --- ------------- -------------------------------------- --- ---------------
    1   1cc1de-4d87c0 HPE J9727A 2920-24G-PoE+-2SFP+ Switch   200 Standby
    2   1cc1de-4dc740 HPE J9727A 2920-24G-PoE+-2SFP+ Switch   128 Commander
    3   1cc1de-4dbd40 HPE J9726A 2920-24G Switch              128 Member
    4   1cc1de-4d79c0 HPE J9728A 2920-48G Switch              175 Member
    5   1cc1de-000005 HPE J9728A 2920-48G Switch              128 Not Joined
    

  2. When a switch that does not match the MAC addresses attempts to join, that switch reboots when the maximum configuration is detected. The active stack logs the following:
    W 10/07/00 06:01:11 03253 stacking: ST3–CMDR: Maximum number of switches in the stack has been reached. 
     Cannot add 1cc1de-4da900 type J9728A

    The failure can be due to one of the strictly provisioned entries being incorrect. To correct this entry, reboot the switch. If there are already 4 switches in the stack, you cannot add additional switches at this time.