Avaya C360 - Manual (Page 136)

Avaya C360 Layer 2 Features
136 Installation and Configuration Guide Avaya C360 Multilayer Stackable Switches, version 4.5
In addition to Link Aggregation Groups - which comprise the basic redundancy mechanism
within the switch - the C360 offers an additional port redundancy scheme. To achieve port
redundancy, you can define a redundancy relationship between any two ports in a stack. One
port is defined as the primary port and the other as the secondary port. If the primary port fails,
the secondary port takes over. You can configure up to 20 pairs of ports (or LAGs) per stack for
port redundancy, and one pair per stack for intermodule redundancy. Each pair contains a
primary and secondary port. You can configure any type of port to be redundant to any other.
Port Redundancy Operation
The Port Redundancy feature supports up to 20 pairs of ports per stack. The redundant or
secondary port takes over when the primary port link is down. Port redundancy provides for the
following in the C360:
● Switchback from the secondary to primary port is allowed
● Switching time intervals can be set by the user
Tip:
Tip:
Port Redundancy interoperates with the Spanning Tree Algorithm.
The Port Redundancy feature functions as follows:
● Port Redundancy enables the user to establish 20 pairs of ports. Within each pair, primary
and secondary ports are defined. To prevent loops, only one port is enabled at a time.
● Following initialization, the primary port is enabled and the secondary port is disabled.
- If the active port link fails, the system enables the secondary port.
- If the secondary port is enabled and the primary port link becomes available again, the
system will "switchback" to the primary port, unless configured otherwise by the user.
● Two timers are available:
- "min-time-between-switchovers" - minimum time (in seconds) between the failure of the
primary port link and switchover to the secondary (backup) port.
Tip:
Tip:
The first time the primary port fails, the switchover is immediate. This timer
applies to subsequent failures.
- "switchback-interval" - the minimum time (in seconds) that the primary port link has to be
up (following failure) before the system switches back to the primary port. If you set this
to zero, there is no switch back.