Debian 10 64 Bits – Ajouter route statique persistente

nano /etc/network/interfaces

auto ens19
iface ens19 inet static
        address 192.168.60.5/24
        up ip route add 10.168.50.0/24 via 192.168.60.1 dev ens19
        down ip route del 10.168.50.0/24 via 192.168.60.1 dev ens19
        up ip route add 192.168.50.0/24 via 192.168.60.1 dev ens19
        down ip route del 192.168.50.0/24 via 192.168.60.1 dev ens19
        up ip route add 192.168.61.0/24 via 192.168.60.1 dev ens19
        down ip route del 192.168.61.0/24 via 192.168.60.1 dev ens19

RTNETLINK answers: No such process

RTNETLINK answers: File exists
ifup: failed to bring up ens19

/bin/sh: 1: route: not found
ifup: failed to bring up ens19

ip addr flush dev ens19