Motorola WiNG 4.4, Reference Manual

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Switch Services 5 - 37
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.
Critical Resource
Enter the IP address of the Critical Resource. When the heartbeat is lost, this
resource will be checked for reachability. The critical resource can be any gateway,
server or host. If the critical resource is not reachable and the heartbeat is still lost,
the switch will de-adopt APs and continue to de-adopt APs until instructed
otherwise.
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.
NOTE: Redundancy uses UDP port 51515 for both source and destination port. The TCP
connection uses 51515 as the destination port, the source port is selected from the range
of 32768 to 61000.