Web/SNMP Management SmartSlot Card User’s Guide 13
Introduction
Watchdog Features
Overview The Management Card is designed to recover from unanticipated
inputs. Through the use of internal, system-wide watchdog
mechanisms, the Management Card can detect most internal problems
and reboot itself to recover.
Network interface
watchdog
mechanism
The Management Card implements numerous internal watchdog
mechanisms to protect itself from becoming inaccessible over the
network. For Example, if within a seven-minute period the Management
Card does not receive any network traffic (either direct, such as SNMP,
or broadcast, such as an Address Resolution Protocol [ARP] request) it
assumes that there is a problem with its network interface and reboots
itself.
The role of the
Default Gateway in
resetting the
network timer
Most networks will have some level of broadcast traffic which will be
received by the Management Card and reset the seven-minute timer to
zero. But since it is not desirable for the Management Card to reboot
just because the network is quiet, the Management Card will attempt to
contact the Default Gateway once every five minutes. If the gateway is
present, it will respond to the Management Card and the seven-minute
timer will be reset to zero.
If your application does not require a gateway or does not have one,
specify the IP address of a computer on the same subnet which is
running on the network most of the time. This will have the same effect
as configuring a gateway.