Recommendations for Configuring Stacks
When deploying a new stack, follow these recommendations for configuring the software:
•
Plan to use the stack as if it were a single multi-slot switch. You need to decide the number and type
of stackable switches in the stack and how the stack ports will be connected to the network.
•
You can physically connect the stack to your networks before the nodes are configured. However,
the default configuration on a switch in non-stacking mode assumes a default untagged VLAN that
contains all switch ports. When first powered on, the switch acts as a Layer 2 switch, possibly
resulting in network loops.
•
Make sure all nodes support the SummitStack feature and are running the same ExtremeXOS
software version. (See the
ExtremeXOS 31.3 Feature License Requirements
.) To view the
ExtremeXOS software version on a node, restart the node and run the command:
show version {
detail
|
process
name
|
images
{
partition
partition
}
{
slot
slot_number
} }
.
If any node does not have the right version, install the correct version on that node. Use the same
image partition on all nodes. After stacking is enabled, images can be upgraded from the stack only
if the same image is selected on all nodes.
•
If you intend to deploy new units that might be part of a stack in the future, turn on stacking mode
during initial deployment to avoid the need for a future restart. The only disadvantages of stacking
mode are the loss of QoS (quality of service) profile QP7 and the reservation of some of the packet
buffer space for stacking control traffic.
•
You can configure the stack by logging into the primary node or any of the other nodes.
•
If the primary-capable stackable switches have different purchased license levels, you might need to
configure license level restrictions on some nodes before those nodes can join the stack. See the
for more information about managing licenses.
•
If the stack supports any feature pack license (such as MPLS or Direct Attach), that feature pack
license must be installed on all primary-capable nodes to support that feature and to prevent traffic
interruption if a failover event occurs.
•
Most stacking specific configurations are effective only after a restart. However, most non-stacking
configuration commands take effect immediately and require no restart.
•
A basic stack configuration can be achieved by using the Easy Setup procedure, as described in the
•
If EAPS, Spanning Tree, or any Layer 2 redundancy protocol is not running on the network, make
sure that your network connections do not form a network loop.
Follow the recommendations in
Recommendations for Placing Switches for Stacked Operation
on page
61 for physically situating your equipment.
Selecting Native and Alternate Stacking Ports
On switches that provide both native stacking ports and alternate stacking ports, you can configure
each logical stacking port to use either the native stacking port or the alternate stacking port. You can
configure logical stacking ports to use any of the following physical stacking port configurations:
•
Two native stacking ports
•
Two alternate stacking ports
Recommendations for Configuring Stacks
Building Stacks
62
ExtremeSwitching 5420 Series Hardware Installation Guide
