"d.gubin" <d.gubin@xxxxxxxxxxx> writes:
> I need to setup QoS on Debian GNU/Linux.
> I am going to use nftables to modify DSCP field in IPv4 Header and tc
> to shape traffic.
>
> Where is packets come in first: in nftables or tc (iproute2) ?
I think this depends on the chain type/hook/priority.
Also, are you talking about egress QoS, or ingress QoS?
If you are completely new to QoS, for egress QoS, try tc-fq_codel
before you resort to hand-tuning DSCP/TOS bits for tc-pfifo_fast.
fq_codel is the default on some systems due to:
https://github.com/systemd/systemd/blob/master/sysctl.d/50-default.conf
If you want an easy test of just the tc qdisc part, OpenSSH sets DSCP bits by default:
ssh example.com # defaults to -o IPQoS=lowdelay
ssh example.com whoami # defaults to -o IPQoS=throughput
sftp example.com # likewise
rsync example.com: # likewise
