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tadams avatar Ubuntu

How to configure DHCP and Static interfaces on Ubuntu 18.04.6 - Destkop

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tadams

/etc/network/interfaces contains the below:

source-directory /etc/network/interfaces.d/*

auto lo
iface lo inet loopback

auto eth1
iface eth1 inet static
    address 192.168.1.10
    netmask 255.255.255.0
    gateway 192.168.1.1

auto eth0
iface eth0 inet dhcp

I have an on-board ethernet adapter that I want to be set for DHCP and also a USB to Ethernet adapter that I want set to 192.168.1.10

If the USB adapter is NOT plugged in on boot, I receive an IP for eth0.

If the USB adapter IS plugged in on boot, I get a static IP 192.168.1.10 for eth1 but no DHCP IPv4 address for eth0

I spent days on this already, any help is appreciated.

EDIT1: this is the /var/log/syslog output with grep applied (grep -E "dhclient|eth0|eth1")

USB to Ethernet adapter is plugged in on boot (no DHCP address assigned to eth0). syslog output:

Mar  6 12:12:36 jetson kernel: [    2.154873] r8152 2-1.3:1.0 eth0: v2.09.00 (2017/08/21)
Mar  6 12:12:36 jetson kernel: [    2.154878] r8152 2-1.3:1.0 eth0: This product is covered by one or more of the following patents:
Mar  6 12:12:38 jetson systemd[1]: Started ifup for eth1.
Mar  6 12:12:38 jetson NetworkManager[4189]: <info>  [1678133558.4103] guessed connection type (eth1) = 802-3-ethernet
Mar  6 12:12:38 jetson NetworkManager[4189]: <info>  [1678133558.4104] update_connection_setting_from_if_block: name:eth1, type:802-3-ethernet, id:Ifupdown (eth1), uuid: 7b635ed6-2640-7ad8-675d-744db12dd9fa
Mar  6 12:12:38 jetson NetworkManager[4189]: <info>  [1678133558.4109] adding eth1 to connections
Mar  6 12:12:38 jetson NetworkManager[4189]: <info>  [1678133558.4109] adding iface eth1 to eni_ifaces
Mar  6 12:12:38 jetson NetworkManager[4189]: <info>  [1678133558.4129] devices added (path: /sys/devices/1003000.pcie/pci0000:00/0000:00:02.0/0000:01:00.0/net/eth1, iface: eth1)
Mar  6 12:12:38 jetson NetworkManager[4189]: <info>  [1678133558.4133] devices added (path: /sys/devices/70090000.xusb/usb2/2-1/2-1.3/2-1.3:1.0/net/eth0, iface: eth0)
Mar  6 12:12:38 jetson NetworkManager[4189]: <info>  [1678133558.4133] device added (path: /sys/devices/70090000.xusb/usb2/2-1/2-1.3/2-1.3:1.0/net/eth0, iface: eth0): no ifupdown configuration found.
Mar  6 12:12:38 jetson NetworkManager[4189]: <info>  [1678133558.4994] keyfile: new connection /run/NetworkManager/system-connections/netplan-eth0.nmconnection (75a1216a-9d1a-30cd-8aca-ace5526ec021,"netplan-eth0")
Mar  6 12:12:38 jetson NetworkManager[4189]: <info>  [1678133558.5210] dhcp-init: Using DHCP client 'dhclient'
Mar  6 12:12:38 jetson kernel: [    5.348192] eth1: 0xffffff800d589000, 48:b0:2d:5c:39:cd, IRQ 407
Mar  6 12:12:38 jetson avahi-daemon[4207]: Joining mDNS multicast group on interface eth1.IPv4 with address 192.168.1.10.
Mar  6 12:12:38 jetson avahi-daemon[4207]: New relevant interface eth1.IPv4 for mDNS.
Mar  6 12:12:38 jetson avahi-daemon[4207]: Registering new address record for 192.168.1.10 on eth1.IPv4.
Mar  6 12:12:38 jetson kernel: [    5.451629] IPv6: ADDRCONF(NETDEV_UP): eth1: link is not ready
Mar  6 12:12:38 jetson NetworkManager[4189]: <info>  [1678133558.6964] manager: (eth0): new Ethernet device (/org/freedesktop/NetworkManager/Devices/3)
Mar  6 12:12:38 jetson NetworkManager[4189]: <info>  [1678133558.7150] manager: (eth1): new Ethernet device (/org/freedesktop/NetworkManager/Devices/4)
Mar  6 12:12:39 jetson networkd-dispatcher[4254]: ERROR:Unknown state for interface NetworkctlListState(idx=3, name='eth0', type='ether', operational='n/a', administrative='unmanaged'): n/a
Mar  6 12:12:39 jetson networkd-dispatcher[4254]: ERROR:Unknown state for interface NetworkctlListState(idx=4, name='eth1', type='ether', operational='n/a', administrative='unmanaged'): n/a
Mar  6 12:12:39 jetson NetworkManager[4189]: <info>  [1678133559.3797] devices added (path: /sys/devices/70090000.xusb/usb2/2-1/2-1.3/2-1.3:1.0/net/eth0, iface: eth0)
Mar  6 12:12:39 jetson NetworkManager[4189]: <info>  [1678133559.3798] device added (path: /sys/devices/70090000.xusb/usb2/2-1/2-1.3/2-1.3:1.0/net/eth0, iface: eth0): no ifupdown configuration found.
Mar  6 12:12:39 jetson NetworkManager[4189]: <info>  [1678133559.3813] device (eth0): state change: unmanaged -> unavailable (reason 'managed', sys-iface-state: 'external')
Mar  6 12:12:39 jetson kernel: [    6.159876] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready
Mar  6 12:12:39 jetson kernel: [    6.176569] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready
Mar  6 12:12:42 jetson NetworkManager[4189]: <info>  [1678133562.7772] device (eth1): carrier: link connected
Mar  6 12:12:42 jetson kernel: [    9.554106] r8168: eth1: link up
Mar  6 12:12:42 jetson kernel: [    9.554147] IPv6: ADDRCONF(NETDEV_CHANGE): eth1: link becomes ready
Mar  6 12:12:43 jetson avahi-daemon[4207]: Joining mDNS multicast group on interface eth1.IPv6 with address fe80::4ab0:2dff:fe5c:39cd.
Mar  6 12:12:43 jetson avahi-daemon[4207]: New relevant interface eth1.IPv6 for mDNS.
Mar  6 12:12:43 jetson avahi-daemon[4207]: Registering new address record for fe80::4ab0:2dff:fe5c:39cd on eth1.*.

EDIT2:

This is my netplan config

network:
  ethernets:
    eth0:
      match:
        macaddress: my_mac_for_onboard_ethernet
      dhcp4: true
    eth1:
      dhcp4: false
      addresses: [192.168.1.10/24]
  version: 2

EDIT3 Here is my updated yaml file - currently no DHCP address on eth0


network:
  version: 2
  renderer: networkd
  ethernets:
    eth0:
      dhcp4: true

    eth1:
      addresses:
        - 192.168.1.10/24
      gateway4: 192.168.1.1
154
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Simon Sudler avatar
us flag
Simon Sudler
The `/etc/network/interfaces/` file look alright. You should check the `/var/log/syslog`. watch out for `dhclient` messages, renaming of network interfaces, etc... if you want help on this, [edit](https://askubuntu.com/posts/1458064/edit) your question and include the logs.
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chili555 avatar
cn flag
chili555
The `/etc/network/interfaces` method is deprecated in Ubuntu 17.10 and later. Its function is now handled in netplan. Is this a desktop (using Network Manager) or server installation? Welcome to Ask Ubuntu.
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chili555 avatar
cn flag
chili555
What does this suggest that your netplan file should read? `cat /usr/share/doc/netplan/examples/static.yaml`
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tadams avatar
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tadams
a nameserver block? I assumed that was handled on the remote DHCP server and required no config on the client side.
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chili555 avatar
cn flag
chili555
The DHCP server doesn't supply DNS nameservers to interfaces declared to be static. Also please check renderer and route.
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tadams avatar
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tadams
I added renderer, but not sure what you meant by route
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tadams avatar
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tadams
The route for eth0 (DHCP assigned) appears to be missing from `ip route` command. When I unplug the eth1 (USB adapter) and reboot, the `ip route` command returns routes for DHCP. Do you know why the routes for eth0 would disappear just because a USB Adapter is plugged in? I would like to avoid declaring the routes in netplan - I want to take the defaults from the DHCP server
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chili555 avatar
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chili555
Netplan won't work if you don't follow its conventions and you certainly can't do what you are trying to do with Network Manager. Please paste the following: `cat /usr/share/doc/netplan/examples/static.yaml` and also: `cat /etc/netplan/*.yaml` Paste the results here and give us the link: http://paste.ubuntu.com
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chili555 avatar
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chili555
Are your interfaces eth0 and eth1 or are they enp3s0 and enp3s1? `ip a`
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tadams avatar
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tadams
They are eth0 and eth1, I tried both but changed the config to eth0 and eith1
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