[LARTC] Multiple shaping on a single physical interface

[Daniel L. Miller]

I have a Linux box connected to a simple DSL router (along with other 
machines on the home network).  This box is intended as an off-site 
storage server for my office.  Taking advantage of some rsync scripts, I 
have a very simple yet complete off-site backup solution.  My question 
is in bandwidth management.

I want to use this box for other purposes.  It has a single NIC, 
connected to the switch/router.  Operating within my home LAN, I should 
be able to communicate with it at the typical full-duplex 100BaseT 
speeds.  However, when it's involved in the archive process, the DSL 
connection (5M/512k) get saturated.  I wanted to setup some sort of 
shaping on this box to control how much of the DSL connection it consumes.

I initially went to wondershaper/ctshaper - but I realized that this is 
actually going to hurt me.  With ctshaper enabled, with the DSL tuned 
settings of 5M/512k - I've absolutely crippled its ability to 
communicate with the LAN.

How can I achieve the clean communication with the DSL, reserving some 
available bandwidth for other purposes - yet leave communication with 
the local network at full?  Do I need to define multiple virtual interfaces?

Daniel