Ubuntu Notes

Netplan

Ubuntu uses Netplan to define the configuration of the system’s network interfaces. To enable Netplan, edit the file ‘/etc/netplan/local.yaml’. Here is an example Netplan configuration, which is encoded as a YAML file;

cat /etc/netplan/local.yaml
network:
  version: 2
  renderer: networkd
  ethernets:
    eno1:
      addresses:
        - 172.18.2.18/24
      nameservers:
        search: [lan]
        addresses: [172.18.2.1]
      routes:
        - to: default
          via: 172.18.2.1

An alternative, encapsulating the local configuration in a bridge. It is functionally equivalent to the basic config above;

network:
  version: 2
  renderer: networkd
  ethernets:
    eno1:
      wakeonlan: true
  bridges:
    br2:
      interfaces: [eno1]
      addresses: [172.18.2.31/24]
      nameservers:
        search: [lan]
        addresses: [172.18.2.1]
      routes:
        - to: default
          via: 172.18.2.1

Another example, now encapsulating the IP interface inside a VLAN interface. Install the vlan package (‘sudo apt install vlan) before using this config;

network:
  version: 2
  renderer: networkd
  ethernets:
    eno1:
      wakeonlan: true
  bridges:
    br2:
      interfaces: [vlan.2]
      addresses: [172.18.2.31/24]
      nameservers:
        search: [lan]
        addresses: [172.18.2.1]
      routes:
        - to: default
          via: 172.18.2.1
  vlans:
    vlan.2:
      id: 2
      link: eno1

Netplan config can be edited, then applied without a reboot, as follows;

sudo netplan generate 
sudo netplan --debug apply

Networking

Create a network bridge, and move the local, static IP address to it. Then, add the local network interface to the bridge. Additional local interfaces, such as virtual machines and other physical network adapters, can be added to the bridge.

sudo brctl addbr br0
sudo ip addr del local 172.18.2.31/24 dev eno1
sudo ip addr add local 172.18.2.31/24 dev br0
sudo brctl addif br0 eno1
sudo ip link set br0 up
sudo ip route add 0.0.0.0/0 via 172.18.2.1
sudo resolvectl dns br0 172.18.2.1

Firefox

Recent versions of Ubuntu install Firefox as a Snap package. There are some teething problems with Snap applications, so installing Firefox through apt is sometimes preferred.

Remove the Snap package and the apt redirect package;

sudo snap remove firefox
sudo apt remove firefox

Add the Mozilla PPA;

sudo apt-add-repository ppa:mozillateam/ppa

Edit ‘/etc/apt/preferences.d/mozillateamppa’ and add;

Package: firefox*
Pin: release o=LP-PPA-mozillateam
Pin-Priority: 501

Install the apt package;

sudo apt install firefox

Darktable

Edit .config/darktable/darktablerc and add the following line;

plugins/darkroom/clipping/extra_aspect_ratios/passport=35:45

PDF Booklet

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