Creating a Two-unit Linear-topology Stack Using Stack Zero-touch Provisioning

Stack zero-touch provisioning elects to form a linear-topology trunk only when the active controller has a linear-topology trunk configuration for itself. If the active controller does not have a linear-topology trunk configuration, stack zero-touch provisioning forms a ring.

The following procedure uses an ICX 7250 stack as an example. A two-unit ICX 7250 stack has two potential linear-topology trunks, (x/2/1 to x/2/4) and (x/2/5 to x/2/8). The system configures a four-port trunk and removes the other direction.

Note: Neither stack interactive-setup nor stack zero-touch provisioning can convert a live two-unit stack to a linear-topology trunk. If you are working with a live system, you can enter the multi-stack-trunk ethernet 1/2/1 to 1/2/4 and ethernet 2/2/1 to 2/2/4 command to change the configuration on both units simultaneously. Refer to Changing a live two-unit stack to a linear-topology trunk for more information.

Complete the following steps to configure a two-unit linear-topology trunk using stack zero-touch provisioning.

Note: For more information on stack zero-touch provisioning, refer to Scenario 2 - Using zero-touch provisioning to configure a stack.

  1. Connect cables between the two units. (In this example, four cables are used as shown in ICX 7250-24P two-unit stack with linear-topology trunk as configured in example).
  2. On the unit that you want to become the active controller, create the desired trunk in stack unit 1 configuration sub-mode. 
    ICX7250# configure terminal
ICX7250(config)# stack unit 1
ICX7250(config-unit-1)# stack-trunk ethernet 1/2/1 to 1/2/4
ICX7250(config-unit-1)# exit
    The example configures ports 1/2/1 through 1/2/4 as a stacking trunk.
  3. On the prospective active controller, enable stacking and zero-touch provisioning as shown in the following example. 
    ICX7250(config)# stack enable
!
ICX7250(config)# stack zero-touch-enable
!

    The first unit detects the other unit within a few minutes.

    The first unit reloads the other unit as a stack member.

    A two-unit stack forms when the member boots up and joins the stack.

  4. Enter the write memory command to save the configuration. 
    ICX7250(config)# write memory

The following example shows the discovery of a two-unit ICX 7250 linear-topology stack using stack zero-touch provisioning. 

ICX7250-48P Router# show stack

***** Warning! stack is not enabled. *****

T=3m56.7: alone: standalone, D: dynamic cfg, S: static
ID   Type          Role    Mac Address    Pri State   Comment
1  S ICX7250-48P   alone   609c.9f99.1988   0 local   None:0


     +---+
  2/1| 1 |2/3
     +---+
Current stack management MAC is 609c.9f99.1988
ICX7250-48P Router# configure terminal
ICX7250-48P Router(config)# stack enable
Enable stacking. This unit actively participates in stacking
ICX7250-48P Router(config)# end
ICX7250-48P Router# stack interactive-setup
You can abort stack interactive-setup at any stage by <ctrl-c>
0: quit
1: change stack unit IDs
2: discover and convert new units (no startup-config flash) to members
3: discover and convert existing/new standalone units to members
2&3 can also find new links and auto-trunk or convert chain(s) to ring.
Please type your selection: 2
Probing topology to find clean units...
T=4m30.7: Sending probes to ports: u1: 1/2/1 to 1/2/4,
Probing in progress ...
Probing in progress ...
Existing stack: ============================================================

     +---+
  2/1| 1 |2/3
     +---+


Horizontal bars link to discovered units. Vertical bars link to stack units.


Chain #0: ==================================================================
SN: serial #, (diff: image mismatch)
#1: icx7250-48p-poe-port 609c.9f99.3f80 SN=DUH3809M02R

     1/2/1
      ||
      ||
      2/1
     +---+
     |#1 |
     +---+

Discovered 1 chain/ring
Chain #0: Do you want to select this chain? (enter 'y' or 'n'): y
#1: icx7250-48p-poe-port 609c.9f99.3f80 SN=DUH3809M02R, type an ID (No: 0, default: 2):

You selected 1 unit(s): #1: ID=2,
There are total two units. The connections qualify a linear-topo that puts all discovered links to a trunk.
Do you want a ring? (y: ring, n: linear-topo chain) (enter 'y' or 'n'): n

stack interactive-setup detects the following links:
Links U1--U2, #=4: 2/1--2/1, 2/2--2/2, 2/3--2/3, 2/4--2/4,


                   #1
     +---+        +---+
     | 1 |2/1==2/1| 2 |
     +---+        +---+

 U1: MAC=609c.9f99.1988 SN=CRK2234J00J running stack interactive-setup
 U2: MAC=609c.9f99.3f80 SN=DUH3809M02R
Proceeding will produce the above topology. Do you accept it? (enter 'y' or 'n'): y
stack interactive-setup discovers 1 unit(s) and sends stack-port/trunk to chain 0: linear-topo: 2/1 to 2/4

T=5m10.7: Please wait for background job to finish.
stack-trunk ethernet 1/2/1 to 1/2/4 replaces stack-port ethernet 1/2/1 and stack-port ethernet 1/2/3

Configuration changed. Please do "write memory".

ICX7250-48P Router#

=================== wait for unit 2 to reload and join the stack ========================

ICX7250-48P Router# show running-config
Current configuration:
!
ver 09.0.00
!
stack unit 1
  module 1 icx7250-48p-poe-port-management-module
  module 2 icx7250-sfp-plus-8port-80g-module
  priority 128
  stack-trunk ethernet 1/2/1 to 1/2/4
stack unit 2
  module 1 icx7250-48p-poe-port-management-module
  module 2 icx7250-sfp-plus-8port-80g-module
  stack-trunk ethernet 2/2/1 to 2/2/4
stack enable
... snipped

ICX7250-48P Router# show stack
T=10m11.2: alone: standalone, D: dynamic cfg, S: static
ID   Type          Role    Mac Address    Pri State   Comment
1  S ICX7250-48P   active  9f99.0000.1988   0 local   Ready
2  D ICX7250-48P   standby 9f99.0000.3f80   0 remote  Ready

    active       standby
     +---+        +---+
     | 1 |2/1==2/1| 2 |
     +---+        +---+
... snipped

ICX7250-48P Router# write memory
Parent topic: Configuring Two-unit Stack Linear-topology Trunks