APC AP9606 User Manual

13

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.

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.

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.