Installation guide

Switch Services
5-38
Heartbeat Period The Heartbeat Period is the interval heartbeat messages are
sent. Heartbeat messages discover the existence and status of
other members within the group. Configure an interval between
1 and 255 seconds. The default value is 5seconds.
Hold Time Define the Hold Time for a redundancy group. If there are no
heartbeats received from a peer during the hold time, the peer is
considered down. In general, the hold period is configured for three
times the heartbeat period. Meaning, if three consecutive
heartbeats are not received from the peer, the peer is assumed
down and unreachable. The hold time is required to be longer than
the heartbeat interval. Configure a hold time between 10 and 255
seconds. The default is 15 seconds.
Handle STP
convergence
Select the Handle STP convergence checkbox to enable
Spanning Tree Protocol (STP) convergence for the switch. In
general, this protocol is enabled in layer 2 networks to prevent
network looping. If the network is enabled for STP to prevent
looping, the network forwards data only after STP convergence.
Enabling STP convergence delays the redundancy state machine
execution until the STP convergence is completed (the standard
protocol value for STP convergence is 50 seconds). Delaying the
state machine is important to load balance access ports at startup.
Enable DHCP
Redundancy
Enables DHCP Redundancy for member switches. DHCP
Redundancy allows an administrator to have only one DHCP server
running at any time in a cluster. The clustering protocol enables all
peers participating in DHCP redundancy to determine the active
DHCP server among them. The switch with lowest Redundancy IP
is selected as the active DHCP server for the cluster. This selected
active DHCP server can be either a primary or standby switch. The
other switches do not provide DHCP service as long as the selected
DHCP server switch is active.
Auto Revert Check this box to enable the Auto Revert feature and specify the
time (in minutes) for the switch to revert. Configure the interval
between 1 and 1800 minutes. The default revert time is 5 minutes.
When a primary switch fails, the standby switch takes over APs
adopted by the primary. If the auto revert feature is enabled, when
the failed primary switch comes back up, the standby starts a timer
based on the auto-revert interval. At the expiry of auto-revert
interval (if the primary switch is still up), the standby switch
releases all adopted APs and goes back to a monitoring mode. The
expiry timer either will be stopped or restarted if the primary switch
goes down and comes up during the auto-revert interval.
Revert Now Reverts an active fail-over standby switch to a passive standby
switch. When a user presses this button, the standby switch will
un-adopt all its adopted APs and move into a standby (passive)
mode only if all configured members are up again. The revert
function does not push APs to the primary switch unless the
primary switch has failed over.