Comment 3 for bug 1791198

same problem for me config provided by ovh

force to delete the netplan file for which starts in dhccp

then put it back and retype netplan try

eno1 in dhcp primary server ip
eno2 ip failover

/etc/netplan/50-cloud-init.yaml

network:
  version: 2
  renderer: networkd
  ethernets:
          eno2:
                  dhcp4: no
                  dhcp6: no
                  addresses: [146.59.XXX.XX/32]
                  gateway4: XX.XX.131.254
                  nameservers:
                          addresses: [213.186.33.99]
                  routes:
                  - to: XX.XX.131.254/32
                    via: 0.0.0.0
                    scope: link

after

netplan try

working

ifconfig

eno1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
        inet XX.XX.131.165 netmask 255.255.255.0 broadcast XX.XX.131.255
        ether ac:1f:XX:XX:51:08 txqueuelen 1000 (Ethernet)
        RX packets 2420464 bytes 645356260 (645.3 MB)
        RX errors 0 dropped 0 overruns 0 frame 0
        TX packets 3516469 bytes 3270577881 (3.2 GB)
        TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

eno2: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
        inet 146.59.XXX.XX netmask 255.255.255.255 broadcast 0.0.0.0
        ether ac:1f:XX:XX:51:09 txqueuelen 10000 (Ethernet)
        RX packets 0 bytes 0 (0.0 B)
        RX errors 0 dropped 0 overruns 0 frame 0
        TX packets 10 bytes 796 (796.0 B)
        TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
        inet 127.0.0.1 netmask 255.0.0.0
        loop txqueuelen 1000 (Local Loopback)
        RX packets 3224040 bytes 10843099504 (10.8 GB)
        RX errors 0 dropped 0 overruns 0 frame 0
        TX packets 3224040 bytes 10843099504 (10.8 GB)
        TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

I have volunteered to replace some part of the ip by X

to not list the exact ip it's not the most important