Moving to Wordpress

Blogger has the distinct 'abandonware' feel to it (and the editor is really frustrating for code snippets), so I'm migrating to Wordpress. You can find past and future posts at djanotes.wordpress.com. I hope you'll join me there.

Comments

Anonymous bridges in netplan

netplan is the default network configuration system for new installs of Ubuntu 18.04 (Bionic). Introduced as the default in Artful, it replaces /etc/network/interfaces . One question that gets asked repeatedly is: "How do I set up an anonymous bridge in netplan?" (An anonymous bridge, I discovered, is one where the bridge doesn't have an IP address; it's more akin to a switch or hub.) It's been approached on Launchpad , and comes up on the IRC channel. If you're trying to create a bridge without an IP address, the obvious first thing to try is this: network: version: 2 ethernets: ens8: match: macaddress: 52:54:00:f9:e9:dd ens9: match: macaddress: 52:54:00:56:0d:ce bridges: br0: interfaces: [ens8, ens9] This is neat, plausible, and wrong - the bridge will be created but will stay 'down'. Per ip a : 5: br0: <BROADCAST,MULTICAST> mtu 15...

Connecting to a wifi network with netplan

How do you connect to a a wifi network with netplan? I hang out on the #netplan IRC channel on Freenode, and this comes up every so often. netplan - the default network configuration tool in Ubuntu 17.10 onwards - currently supports WPA2 Personal networks, and open (unencrypted) networks only. If you need something else, consider using NetworkManager directly, or falling back to ifupdown and wpa_supplicant for a little longer. Without further ado, here are tested, working YAML files for connection to my local WPA2 and unencrypted network. The only things that have been changed are the SSIDs and password. Both networks have a router providing dhcp4. In both cases I assume there's only one wifi device in the system - if this is not true, replace match: {} with something more specific. You can drop these in /etc/netplan and run netplan generate; netplan apply and things should work. The network will also be brought up on subsequent boots. Note that, as always in YAML...

Painless powerpc cross-compiling

As an ex-IBMer, I'm still quite fond of POWER/ppc64 processors, and occasionally cross-compile kernels for 64-bit little-endian PowerPC (ppc64el/ppc64le) from my amd64 system. It's not immediately obvious what the simplest way to do this is. On Ubuntu (and I'm told, Debian) it is really very simple. Installation sudo apt install gcc-powerpc64le-linux-gnu Congrats, you now have a ppc64le cross-compiling toolchain installed! If you need other languages, g++/gccgo/gfortran/gnat/gobjc-powerpc64le-linux-gnu are also available. Kernel cd your/linux/source make ARCH=powerpc CROSS_COMPILE=powerpc64le-linux-gnu- <your usual kernel build commands here> That's it. Userspace It depends a bit on the build system. Here's how to build, for example, sed , which uses autotools ( ./configure and friends). ./configure --host powerpc64le-linux-gnu make That's it. For a dynamically linked binary, you only need the headers for any library depende...

Daniel's Notes

Search This Blog