A note on the bandwidth definition used in this file:
kbps
mbps
kbit
mbit
bps or number
k or kb
m or mb
The columns in the file are as follows (where the column name is followed by a different name in parentheses, the different name is used in the alternate specification syntax).
INTERFACE
TYPE - [external|internal]
IN-BANDWIDTH (in_bandwidth) - {-|bandwidth[:burst]|~bandwidth[:interval:decay_interval]}
If you don't want any traffic to be dropped, set this to a value to zero in which case Shorewall will not create an ingress qdisc.Must be set to zero if the REDIRECTED INTERFACES column is non-empty.
The optional burst option was added in Shorewall 4.4.18. The default burst is 10kb. A larger burst can help make the bandwidth more accurate; often for fast lines, the enforced rate is well below the specified bandwidth.
What is described above creates a rate/burst policing filter. Beginning with Shorewall 4.4.25, a rate-estimated policing filter may be configured instead. Rate-estimated filters should be used with Ethernet adapters that have Generic Receive Offload enabled by default. See m[blue]Shorewall FAQ 97am[][2].
To create a rate-estimated filter, precede the bandwidth with a tilde ("~"). The optional interval and decay_interval determine how often the rate is estimated and how many samples are retained for estimating. Please see m[blue]http://ace-host.stuart.id.au/russell/files/tc/doc/estimators.txtm[] for details. If not specified, the default interval is 250ms and the default decay_interval is 4sec.
OUT-BANDWIDTH (out_bandwidth) - [rate[:[burst][:[latency][:[peek][:[minburst]]]]]]
Shorewall provides defaults as follows:
/etc/shorewall/tcinterfaces
m[blue]http://ace-host.stuart.id.au/russell/files/tc/doc/sch_tbf.txtm[]
m[blue]http://ace-host.stuart.id.au/russell/files/tc/doc/estimators.txtm[]
shorewall(8)