lxc: pull in networking and templates via RRECOMMENDS

The lxc recipe ships three sub-packages: ${PN}, ${PN}-networking, and
${PN}-templates. ${PN} contains the lxc-* command-line binaries.
${PN}-networking owns lxc-net.service, /etc/default/lxc-net, the
dnsmasq drop-in for the lxcbr0 bridge, and the firewall plumbing.
${PN}-templates owns /usr/share/lxc/templates, the per-distro
container-creation scripts that lxc-create invokes via --template.

Installing only the main ${PN} package leaves a non-functional LXC.
There's no lxcbr0 bridge, so any container whose config references it
(every download-template default config does) fails to start with

  network.c: netdev_configure_server_veth: Failed to attach "vethXXX"
             to bridge "lxcbr0", bridge interface doesn't exist

and there are no template scripts, so lxc-create --template <foo>
has nothing to invoke. The user-facing toolchain is effectively broken
unless the integrator knows to add the sub-packages by hand.

Pull both sub-packages in through RRECOMMENDS so any image that
installs lxc gets a functional LXC by default, regardless of whether
the install path is packagegroup-lxc, IMAGE_INSTALL:append, or
CORE_IMAGE_EXTRA_INSTALL. Integrators who don't want them (custom
networking, hand-written templates) can drop either or both through
BAD_RECOMMENDATIONS.

Signed-off-by: Bruce Ashfield <bruce.ashfield@gmail.com>

1 files changed, 11 insertions, 0 deletions

diff --git a/recipes-containers/lxc/lxc_git.bb b/recipes-containers/lxc/lxc_git.bb
index ec26f2c8..d6544073 100644
--- a/recipes-containers/lxc/lxc_git.bb
+++ b/recipes-containers/lxc/lxc_git.bb
@@ -32,6 +32,17 @@ RDEPENDS:${PN} = " \
 
 RDEPENDS:${PN}:append:libc-glibc = " glibc-utils"
 
+# Soft-pull the layer's own sub-packages so a default `lxc` install lands a
+# functional LXC. Without networking, lxc-net.service is missing and lxcbr0
+# never comes up, so any container whose config references lxcbr0 (the
+# download template's default) fails to start with:
+#   network.c: netdev_configure_server_veth: Failed to attach "vethXXX" to
+#   bridge "lxcbr0", bridge interface doesn't exist
+# Without templates, lxc-create --template <foo> has no template scripts
+# to invoke. Users who genuinely don't want either can drop them with
+# BAD_RECOMMENDATIONS.
+RRECOMMENDS:${PN} += "${PN}-networking ${PN}-templates"
+
 RDEPENDS:${PN}-ptest += "file make gmp nettle gnutls bash libgcc"
 
 RDEPENDS:${PN}-networking += "iptables"