I'm trying to set up a traffic control on ingress attaching a egress qdisc to
the ifb device. The idea is to use a RED algorithm instead of policing
the incoming traffic. After trying with tc-red and not obtaining the
expected results, I decided to try with something easier, and use htb
as bottleneck:
ifconfig ifb0 up
tc qdisc del dev $dev ingress
tc qdisc del dev ifb0 root
tc qdisc add dev $dev ingress
tc filter add dev $dev parent ffff: protocol ip prio 10 u32 \
match u32 0 0 flowid 1:\
action mirred egress redirect dev ifb0
(1) tc qdisc add dev ifb0 root handle 1: htb default 1
(2) tc class add dev ifb0 parent 1: classid 1:1 htb burst 0 rate 112kbit
Now I generate some traffic:
$ scp user@host1:~/reallylargefile .
reallylargefile 0% 64KB 12.4KB/s 7:52:29
and I get the expected results, if instead of htb I use something like
RED, changing lines (1) and (2) with
tc qdisc add dev ifb0 root handle 1: red limit 256000 min 1 max 32000
avpkt 1 burst 1 probability 0.8 bandwidth 512
I don's see any dropped packets at all. (I know that the values of min,
avpkt and burst are extremely low, and that probability is extremely
high, but I just tweakeed them hopping to see dropped packets)
Did I completely misunderstod the how red works?