QoS for 3CX VoIP on Debian Linux

[keven.bernier]

Hello

I own the 3cx V16 update 3 version and I would like to implant the QoS by following this procedure (https://www.3cx.com/blog/voip-howto/qos-linux/ ). I get an error in the Debian
error:
iptables -t mangle -A OUTPUT -p udp -j DSCP –set-dscp 56
Bad argument –set-dscp' Try iptables -h' or 'iptables --help' for more information.


The Debian is in version 9

Has the procedure changed?

Thank you

 

[keven.bernier]

I solved my problem it was missing a dash after DSCP