Configuring Two-unit Stack Linear-topology Trunks

The text in this draft comment is a duplicate of what appears in the section "Support for two-unit stack linear-topology trunks" in the section on changes with 08.0.90 earlier in the guide. The exception is that the exposed "Support..." section includes a link to this one. Consider removing and linking to the next underlying section. MLW

FastIron 08.0.90 and later releases support a linear-topology trunk in a two-unit stack. A two-unit stack can form a linear-topology trunk containing all stacking ports, instead of dividing the ports into the two directions of a ring topology. The linear-topology trunk provides the same redundancy as a two-unit ring because of trunk load balancing. Furthermore, a linear-topology trunk doubles the bandwidth of the stacking ports between two units.

In a two-unit ring topology, only one direction is used even though there are two paths for a unit to reach the other unit. In contrast, a linear-topology trunk uses all ports to reach the other unit.

Note: In a ring of more than two units, all directions of any unit are fully utilized because each direction is to a different unit. Therefore, the linear-topology trunk is not supported in a stack of more than two units.

Note: A linear-topology trunk cannot co-exist with another stack-port or stack-trunk in the same unit. Therefore, if you configure a linear-topology trunk, the original stack-port or stack-trunk configuration is removed. If a unit has a linear-topology trunk and you configure a stack-port or stack-trunk, the linear-topology trunk is removed.

In this section:

  1. Building a Two-unit Linear-topology Trunk Manually
  2. Building a Two-unit Stack with a Linear-topology Trunk Using Stack Interactive-setup
  3. Creating a Two-unit Linear-topology Stack Using Stack Zero-touch Provisioning
  4. Changing a Live Two-unit Stack to a Linear-topology Trunk
  5. Changing a Live Linear-topology Trunk to a Ring
Parent topic: Building a Stack