@@ -75,16 +75,35 @@ case "$lsb_dist" in

 	Ubuntu|Debian)

 		export DEBIAN_FRONTEND=noninteractive

-		# TODO remove this comment/section once device-mapper lands

-		echo 'Warning: Docker currently requires AUFS support in the kernel.'

-		echo 'Please ensure that your kernel includes such support.'

-		( set -x; sleep 10 )

+		did_apt_get_update=

+		apt_get_update() {

+			if [ -z "$did_apt_get_update" ]; then

+				( set -x; $sh_c 'sleep 3; apt-get update' )

+				did_apt_get_update=1

+			fi

+		}

+		

+		# TODO remove this section once device-mapper lands

+		if ! grep -q aufs /proc/filesystems && ! modprobe aufs; then

+			kern_extras="linux-image-extra-$(uname -r)"

+			

+			apt_get_update

+			( set -x; $sh_c 'sleep 3; apt-get install -y -q '"$kern_extras" ) || true

+			

+			if ! grep -q aufs /proc/filesystems && ! modprobe aufs; then

+				echo >&2 'Warning: tried to install '"$kern_extras"' (for AUFS)'

+				echo >&2 ' but we still have no AUFS.  Docker may not work. Proceeding anyways!'

+				( set -x; sleep 10 )

+			fi

+		fi

 		if [ ! -e /usr/lib/apt/methods/https ]; then

-			( set -x; $sh_c 'sleep 3; apt-get update; apt-get install -y -q apt-transport-https' )

+			apt_get_update

+			( set -x; $sh_c 'sleep 3; apt-get install -y -q apt-transport-https' )

 		fi

 		if [ -z "$curl" ]; then

-			( set -x; $sh_c 'sleep 3; apt-get update; apt-get install -y -q curl' )

+			apt_get_update

+			( set -x; $sh_c 'sleep 3; apt-get install -y -q curl' )

 			curl='curl -sL'

 		fi

 		(