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Q. The LAN link LED is green on my NetDog, but I can't poll it from my T/Mon.
A. Some routers will not forward packets to an IP address until the MAC address of the destination device has
been registered on the router's Address Resolution Protocol (ARP) table. Enter the IP address of your
gateway and your T/Mon system to the ARP table.
Q. What do the terms "port," "address," "display" and "alarm point" mean?
A. These terms refer to numbers that designate the location of a network alarm, from the most general (a port to
which several devices are connected) to the most specific (an individual alarm sensor).
Port: A number designating a serial port through which a monitoring device collects data.
Address: A number designating a device connected to a port.
Display: A number designating a logical group of 64 alarm points.
Alarm Point: A number designating a contact closure that is activated when an alarm condition occurs. For
example, an alarm point might represent a low oil sensor in a generator or an open/close sensor in a door.
These terms originally referred only to physical things: actual ports, devices, and contact closures. For the
sake of consistency, port-address-display-alarm point terminology has been extended to include purely
logical elements: for example, the NetDog reports internal alarms on Port 99, Address 1.
Q. What characteristics of an alarm point can be configured through software? For instance, can point 4
be used to sense an active-low signal, or point 5 to sense a level or an edge?
A. The NetDog's standard configuration is for all alarm points to be level-sensed. You cannot use configuration
software to convert alarm points to TTL (edge-sensed) operation. TTL alarm points are a hardware option
that must be specified when you order your NetDog. Ordering TTL points for your NetDog does not add to
the cost of the unit What you can do with the configuration software is change any alarm point from
"Normal" to "Reversed" operation. Switching to Reversed operation has different effects, depending on the
kind of input connected to the alarm point:
·
If the alarm input generates an active-high signal, switching to Reversed operation means the NetDog
will declare an alarm in the absence of the active-high signal, creating the practical equivalent of an
active-low alarm.
·
If the alarm input generates an active-low signal, switching to Reversed operation means the NetDog
will declare an alarm in the absence of the active-low signal, creating the practical equivalent of an
active-high alarm.
·
If the alarm input is normally open, switching to Reversed operation converts it to a normally closed
alarm point.
·
If the alarm input is normally closed, switching to Reversed operation converts it to a normally open
alarm point.
Q. How do I back up my NetDog configuration?
A. You can use File Transfer Protocol (FTP) to read and write configuration files to the NetDog's NVRAM, but
you can't use FTP to edit configuration files.
SNMP FAQs
14.2
Q. Which version of SNMP is supported by the SNMP agent on the NetDog?
A. SNMP v1 and v2c.
Q. How do I configure the NetDog to send traps to an SNMP manager? Is there a separate MIB for the
NetDog? How many SNMP managers can the agent send traps to? And how do I set the IP address of
the SNMP manager and the community string to be used when sending traps?
A. The NetDog begins sending traps as soon as the SNMP managers are defined. The NetDog MIB is included
on the NetDogResource CD. The MIB should be compiled on your SNMP manager. (Note: MIB versions
may change in the future.) The unit supports a main SNMP manager, which is configured by entering its IP
address in the Trap Address field of Ethernet Port Setup. You can also configure up to eight secondary
Summary of Contents for NetDog 82 BW
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