[Bug 1872589] Re: systemd-networkd is not honoring UseRoutes=false

[Rafael David Tinoco]

*** This bug is a duplicate of bug 1867375 ***
    https://bugs.launchpad.net/bugs/1867375

Ahhh good to know, documentation in netplan.io doesn't reflect that
also, that is why I opened the bug. Funny because because of the
attribute name "UseRoutes" I was in doubt if it would get the default
gateway or just the published routes.. then the documentation said it
would get the default GW.

Thanks for letting me know Dan!

-> https://netplan.io/reference

Documenting it if anyone is confused by this as well:

"""
use-routes (bool)
Default: true. When true, the routes received from the DHCP server will be installed in the routing table normally. When set to false, routes from the DHCP server will be ignored: in this case, the user is responsible for adding static routes if necessary for correct network operation. This allows users to avoid installing a default gateway for interfaces configured via DHCP. Available for both the networkd and NetworkManager backends.
"""

-- 
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/1872589

Title:
  systemd-networkd is not honoring UseRoutes=false

Status in systemd package in Ubuntu:
  Triaged

Bug description:
  When netplan configures dhcp4-overrides and set "use-routes" to false,
  systemd-networkd should be configured with UseRoutes=false. It is.
  Unfortunately looks like systemd-networkd is not honoring it and
  configuring the default gateways for the interfaces no matter what.

  Ubuntu Focal: systemd: 245.4-2ubuntu1

  ----

  $ sudo cat /etc/netplan/50-cloud-init.yaml
  network:
      ethernets:
          enp5s0:
              match:
                  macaddress: 00:16:3e:af:c4:d6
              set-name: eth0
              dhcp4: true
              dhcp-identifier: mac
          enp6s0:
              match:
                  macaddress: 00:16:3e:50:11:9c
              set-name: iscsi01
              dhcp4: true
              dhcp-identifier: mac
              dhcp4-overrides:
                use-routes: false
          enp7s0:
              match:
                  macaddress: 00:16:3e:b3:cc:50
              set-name: iscsi02
              dhcp4: true
              dhcp-identifier: mac
              dhcp4-overrides:
                use-routes: false
      version: 2
      renderer: networkd

  ----

  $ cat /var/run/systemd/network/10-netplan-enp6s0.network

  [Match]
  MACAddress=00:16:3e:50:11:9c
  Name=iscsi01

  [Network]
  DHCP=ipv4
  LinkLocalAddressing=ipv6

  [DHCP]
  ClientIdentifier=mac
  RouteMetric=100
  UseMTU=true
  UseRoutes=false

  --

  $ ip route show | grep default
  default via 10.250.93.1 dev iscsi02 proto dhcp src 10.250.93.101 metric 100
  default via 10.250.94.1 dev iscsi01 proto dhcp src 10.250.94.167 metric 100
  default via 10.250.97.1 dev eth0 proto dhcp src 10.250.97.123 metric 100

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1872589/+subscriptions