Comment 77 for bug 1573272

> In vlan ifupdown pre-up script, instead of calling ip link up for raw device before creating vlan interface, do a full ifup for raw device.

Doing so introduces another kind of problem. Consider the following setup:

auto eno1
iface eno1 inet dhcp

auto eno1.101
iface eno1.101 inet manual
  vlan-raw-device eno1

In this case, ifup is calling dhclient that then exits, leaving eno1 interface in a state when DHCP lease never gets renewed:

/bin/sh /lib/udev/vlan-network-interface
 \_ /bin/sh /etc/network/if-pre-up.d/vlan
     \_ ifup eno1
         \_ /bin/sh -c /sbin/dhclient -1 -v -pf /run/dhclient.eno1.pid -lf /var/lib/dhcp/dhclient.eno1.leases -I -df /var/lib/dhcp/dhclient6.eno1.leases eno1 .
             \_ /sbin/dhclient -1 -v -pf /run/dhclient.eno1.pid -lf /var/lib/dhcp/dhclient.eno1.leases -I -df /var/lib/dhcp/dhclient6.eno1.leases eno1