AMatechak's questions

On 18.04. I'm trying to configure my server with 2 vlan interfaces. Each vlan interface will have a separate IP Address on a separate subnet, and both will be linked to same physical interface. When I configure the vlan interfaces, I have connectivity to each different subnet through the vlans, but I am unable to add any additional routes. I need to add a default route with a next-hop on one of the subnets (vlan2000), and then a static route to a single, unattached subnet through the other vlan (vlan1000). Here is my netplan config file:

network:
renderer: NetworkManager
version: 2
ethernets:
    enp0s31f6: 
        routes:
            - to: 0.0.0.0/0
              via: 192.168.100.2
              metric: 100
            - to: 192.168.1.0/24
              via: 172.16.100.1
              metric: 10
vlans:
    vlan1000:
        id: 1000
        link: enp0s31f6
        addresses: [ "172.16.100.2/30" ]
    vlan2000:
        id: 2000
        link: enp0s31f6
        addresses: [ "192.168.100.2/24" ]

I have also tried adding the applicable routes under each vlan hierarchy with no luck -- for example:

    vlans:
    vlan1000:
        id: 1000
        link: enp0s31f6
        addresses: [ "172.16.100.2/30" ]
        routes:
          - to: 0.0.0.0/0
          via: 192.168.100.2
          metric: 100

With both of these, after applying the config I get the following error:

Traceback (most recent call last):
  File "/usr/sbin/netplan", line 23, in <module>
    netplan.main()
  File "/usr/share/netplan/netplan/cli/core.py", line 50, in main
    self.run_command()
  File "/usr/share/netplan/netplan/cli/utils.py", line 130, in run_command
    self.func()
  File "/usr/share/netplan/netplan/cli/commands/apply.py", line 43, in run
    self.run_command()
  File "/usr/share/netplan/netplan/cli/utils.py", line 130, in run_command
    self.func()
  File "/usr/share/netplan/netplan/cli/commands/apply.py", line 93, in command_apply
    stderr=subprocess.DEVNULL)
  File "/usr/lib/python3.6/subprocess.py", line 291, in check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['udevadm', 'test-builtin', 'net_setup_link', '/sys/class/net/vlan1000']' returned non-zero exit status 4.

If I then apply it again, it goes through, but none of the routes are added to the routing table. If i remove the route statements entirely, it applies with no errors. I don't know much about netplan but that seems like the issue. So i'm assuming I'm doing something in the config incorrectly. Where am i supposed to add statis routes for vlan interfaces?

FTR, when I add the static routes manually:

 sudo ip route add 192.168.1.0/24 via 172.16.100.1 dev vlan1000

everything works as I'm expecting it to. My concern is that i don't believe those manually added routes will persist after a restart. If there is an easier work around to make those routes persist I am open to that.

Thanks,