[mrtg] Interface indentification under Windows

[Steve Shipway]

> can someone explain me, what EXACTLY means those values if I want to run
> cfgmaker under windows, please?
> 
> --ifref=eth          ... by Ethernet Number
> --ifref=descr        ... by Interface Description
> --ifref=name         ... by Interface Name
> 
> because I try hard, spend many hours searching the Web, inside of my
> windows, but I still do not understand :-(

At a DOS command line, type 'netstat -r'

The 'Interface List' at the top will show the interface number (0x1, 0x2...) followed by MAC address and Interface description.

These three items correspond to the information given about an interface by SNMP.  The number is 0,1,2.... sequentially.  The description (rarely used) is the pretty name shown in Windows for the interface.  The Name is usually something like 'eth0', 'eth1'... for Ethernet and 'lo0' for loopback, and so on.  I can't give you an example because we don't have any SNMP-enabled Windows boxes here.

MRTG needs a unique way to refer to the interface.  Usually, using IP address is the best, but if you can't use that, maybe the interface name or description will work.  As a last resort, you can use the Ethernet number.  The problem with these methods is that the number and name can change if new interfaces are added, and the description is user configurable and so can change rather easily.  However the Description is good for the ifdescr= option.

HTH

Steve