[Bug 2060778] Re: netplan, multiple dhcp route with metric failure

[Csillagszemű Pityesz]

As far as I know I am not using NetworkManager, 'nmcli dev' shows the
following:

DEVICE  TYPE      STATE       CONNECTION 
virbr0  bridge    nem kezelt  --         
vm-br0  bridge    nem kezelt  --         
lan     ethernet  nem kezelt  --         
lo      loopback  nem kezelt  --         
iscsi   vlan      nem kezelt  --         
vm      vlan      nem kezelt  --

('nem kezelt' means not managed; the 'iscsi' interface is a statically
configured vlan device to access the VM storage backend)

My usecase is somewhat special as I use the desktop distribution with a
somewhat more complicated setup than usual because I need to use
networked VMs for my work. I am using networkd as I thought it would be
more appropriate than NetworkManager.

Upon further investigation to the original matter I believe it is really
an issue with systemd-resolved instead of netplan, so sorry for taking
your time. My local router resolves hostnames differently for the host
and the VM networks. After startup or issuing a 'netplan apply' after
resume the resolver for the host ('lan' network) is being used as
primary, BUT after resume not issuing a 'netplan apply' command somehow
the resolver for the VM network takes precedence - which is bad. Then
the host will obviously try to access the 'misresolved' systems through
the wrong gateway, which is really only the symptom not the cause.

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to systemd in Ubuntu.
https://bugs.launchpad.net/bugs/2060778

Title:
  netplan, multiple dhcp route with metric failure

Status in Netplan:
  Incomplete
Status in systemd package in Ubuntu:
  New

Bug description:
  Hardware/network: PC with single NIC, multiple vlans:
   - untagged: default LAN, should be used by the host
   - vlan 15: VM network, should only be used by the VM(s) running on the host

  Netplan config:

  network:
    version: 2
    renderer: networkd
    ethernets:
      lan:
        match:
          macaddress: "XX:XX:XX:XX:XX:XX"
        set-name: lan
        mtu: 9000
        dhcp4: yes
        dhcp6: yes
        ipv6-privacy: true
    bridges:
      vm-br0:
        dhcp4: yes
        interfaces: [vm]
        dhcp4-overrides:
          route-metric: 200
    vlans:
      vm:
        id: 15
        link: lan

  (Using networkd as the renderer some apps [App Store, Settings/Online Accounts,...] thinks I'm offline in ubuntu.)
  The main problem is with this setup is that after resume the route metrics get mixed up, and the host tries to use the VM network as its default route.
  Adding a 'dhcp4-overrides: {route-metric: 10}' stanza to LAN - as the netplan documentation suggests - results in the interfaces not coming up. (Issuing 'netplan try' results in 'Warning: The unit file, source configuration file or drop-ins of netplan-ovs-cleanup.service changed on disk. Run 'systemctl daemon-reload' to reload units.'.)

To manage notifications about this bug go to:
https://bugs.launchpad.net/netplan/+bug/2060778/+subscriptions