Archlinux Linux Container ALSA configuration (pre-systemd)

#
# Create a basic container (Arch Linux)
#

cd /srv/lxc
mkarchroot mycontainer base
cat > /etc/lxc/mycontainer.conf << EOF
# hostname
lxc.utsname = mycontainer
#
# network
#     if the network is not defined then the container
#     will be able to use the host's network
lxc.network.type = veth
lxc.network.flags = up
lxc.network.link = br0
lxc.network.name = eth0
lxc.network.mtu = 1500
lxc.network.ipv4 = 10.0.200.3/8
#
# only explicit device access
lxc.cgroup.devices.deny = a
#
# Memory Devices
lxc.cgroup.devices.allow = c 1:3 rwm # /dev/null      null stream
lxc.cgroup.devices.allow = c 1:5 rwm # /dev/zero      zero stream
lxc.cgroup.devices.allow = c 1:7 rwm # /dev/full      full stream
lxc.cgroup.devices.allow = c 1:8 rwm # /dev/urandom   blocking random stream
lxc.cgroup.devices.allow = c 1:9 rwm # /dev/random    non blocking stream
#
# Terminals
lxc.tty =1                           #                allow one tty
lxc.cgroup.devices.allow = c 4:0 rwm # /dev/tty0      current virtual terminal
lxc.cgroup.devices.allow = c 5:0 rwm # /dev/tty       current tty device
lxc.cgroup.devices.allow = c 5:1 rwm # /dev/console   system console
lxc.cgroup.devices.allow = c 5:2 rwm   # /dev/ptmx    pseudo terminal creator
lxc.cgroup.devices.allow = c 136:* rwm # /dev/pts/*   psuedo terminal slaves
#
# root filesystem
lxc.rootfs = /srv/lxc/mycontainer
#
# mounts
lxc.mount = /etc/lxc/mycontainer.fstab
EOF
cat > /etc/lxc/mycontainer.fstab << EOF
none /srv/lxc/mycontainer/dev/pts devpts defaults 0 0
none /srv/lxc/mycontainer/dev/shm tmpfs defaults 0 0
none /srv/lxc/mycontainer/proc proc defaults 0 0
none /srv/lxc/mycontainer/sys sysfs defaults 0 0
EOF
lxc-create -f /etc/lxc/mycontainer.conf -n mycontainer
cd /srv/lxc/mycontainer/dev
rm -rf *
mknod -m 666 null c 1 3      # null stream
mknod -m 666 zero c 1 5      # zero stream
mknod -m 666 full c 1 7      # full stream
mknod -m 666 random c 1 8    # blocking random stream
mknod -m 666 urandom c 1 9   # non blocking stream
mknod -m 600 tty0 c 4 0      # current virtual terminal
mknod -m 666 tty c 5 0       # process's current tty device
mknod -m 600 console c 5 1   # system console aka tty0
mknod -m 666 ptmx c 5 2      # pseudo terminal creator
mkdir -m 755 pts             # psuedo terminal slaves
mkdir -m 1777 shm            # shared memory
mknod -m 600 initctl p       # init control channel
mknod -m 600 tty1 c 4 1           # tty1 virtual console
sed -i '/c[2-9]/d' /srv/lxc/mycontainer/etc/inittab
cat > /srv/lxc/mycontainer/etc/rc.sysinit << EOF
#!/bin/bash

# Clean out old daemon/service pids from the container
rm -f $(find /var/run -name '*pid')
rm -f /var/lock/subsys/*

# network (or use a DHCP client here)
route add default gw 10.0.0.138
echo > /etc/resolv.conf search your-domain
echo >> /etc/resolv.conf nameserver 10.0.0.138


# Initally we don't have any container originated mounts
rm -f /etc/mtab
touch /etc/mtab''
EOF
rm -f /srv/lxc/mycontainer/etc/localtime
cp /usr/share/zoneinfo/GB /srv/lxc/mycontainer/etc/localtime
cp /etc/pacman.d/mirrorlist /srv/lxc/mycontainer/etc/pacman.d/mirrorlist


#
# Setup mycontainer with Alsa. Do this on the host
#

cat >> /etc/lxc/mycontainer.conf << EOF
# For ALSA Sound
lxc.cgroup.devices.allow = c 116:* rwm # dev/snd/
EOF

#
# Script to creae sound devices. You may need to hand paste this if it
# doesn't work with cat.
#

cat > /srv/lxc/make_sound_devices << EOF
#!/bin/bash
LXC_ROOT=/srv/lxc
CONTAINERS="mycontainer"

for CONTAINER in $CONTAINERS
do
    rm -rf ${LXC_ROOT}/${CONTAINER}/dev/snd
    mkdir -p ${LXC_ROOT}/${CONTAINER}/dev/snd
done

ifs_char=$IFS
IFS=$'\n'
ifs_line=$IFS
for i in $(ls -l /dev/snd | grep '^c' | awk -F "[ ,]" {'print "mknod -m 660 ${LX
C_ROOT}/${CONTAINER}/dev/snd/"$12" c "$5" "$7" && chown root:audio ${LXC_ROOT}/$
{CONTAINER}/dev/snd/"$12'})
do
    IFS=$ifs_char
    for CONTAINER in $CONTAINERS
    do
      eval $i
    done
    IFS=$ifs_line
done
EOF

#
# make the sound devices using above script
#
chmod +x /srv/lxc/make_sound_devices
/srv/lxc/make_sound_devices

#
# recreate and start the container
#

lxc-destroy -n mycontainer
lxc-create -f /etc/lxc/mycontainer.conf -n mycontainer

/usr/bin/screen -dmS screen-mycontainer /usr/bin/lxc-start -n mycontainer

#
# enter the container
#

lxc-console -n mycontainer
root

#
# setup locale and update
#
usr/sbin/locale-gen
pacman -Syy
pacman -Syu


#
# setup ALSA
#

pacman -S alsa-utils


#
# test it works
#
aplay /usr/share/sounds/alsa/Front_Center.wav