[OT] Linux equivalent of MT connection-mark=no-mark ?

RouterOS General
1

Hello,

In nftables or iptables language, what could be the equivalent of Mikrotik’s connection-mark=no-mark ?

Semantic: “if an un- marked packet is received in interface ISP_1, then add mark it with 17 mark”
/ip firewall mangle

MT implementation
addchain=input connection-mark=no-mark in-interface=ISP_1 action=mark-connection new-connection-mark=17

nftables implementation
add rule ip mangle input iifname “ens3.932” meta FOOBAR meta mark set 17

What shall I replace FOOBAR with to get something strictly equivalent of MT implementation ?
In other words, what is default mark in Linux ? Is it 0 ? Is it 1 ? Something else ?

Cheers

PS: Please, apologize if this is a bit Off-Topic but, given the high number of factor that may influence my lab testing, help from experienced readers would be be of great value.

2

The kernel assigns default mark of 0, so “meta mark 0” I would assume.

3

or “not 17”

4

Thanks for replying !