Added degraded-raid-fix recipe

README.md

@@ -18,6 +18,7 @@ The following platforms are supported by this cookbook, meaning that the recipes
 ## Recipes
 
 * `mdadm` - The default recipe.
+* `mdadm::degraded-raid-fix` - Recipe for fixing a boot race condition where Ubuntu thinks the RAID is degraded.
 
 # Usage
 

files/default/mdadm-functions

@@ -0,0 +1,122 @@
+#!/bin/sh
+
+txt_message ()
+{
+        if [ -x /bin/plymouth ] && plymouth --ping; then
+	    return 0
+        else
+                echo "$@" >&2
+        fi
+        return 0
+}
+
+message()
+{
+        if [ -x /bin/plymouth ] && plymouth --ping; then
+                plymouth message --text="$@"
+        else
+                echo "$@" >&2
+        fi
+        return 0
+}
+
+
+degraded_arrays()
+{
+	udevadm settle
+	mdadm --misc --scan --detail --test >/dev/null 2>&1
+	return $((! $?))
+}
+
+mountroot_fail()
+{
+	if degraded_arrays; then
+		txt_message "
+** WARNING: There appears to be one or more degraded RAID devices **
+
+The system may have suffered a hardware fault, such as a disk drive
+failure.  The root device may depend on the RAID devices being online. One
+or more of the following RAID devices are degraded:
+"
+		txt_message "`cat /proc/mdstat`"
+
+		BOOT_DEGRADED="false"
+		# Read BOOT_DEGRADED from file
+		if [ -r "/conf/conf.d/mdadm" ]; then
+			. /conf/conf.d/mdadm
+		fi
+		# But allow for overides on the kernel command line
+		for x in $(cat /proc/cmdline); do
+			case $x in
+				bootdegraded)
+					BOOT_DEGRADED="true"
+				;;
+				bootdegraded=*)
+					BOOT_DEGRADED=${x#bootdegraded=}
+				;;
+			esac
+		done
+		# Allow for a couple of permutations, {true|1|yes|on}
+		case "$BOOT_DEGRADED" in
+			1)    BOOT_DEGRADED="true";;
+			yes)  BOOT_DEGRADED="true";;
+			on)   BOOT_DEGRADED="true";;
+		esac
+		# Check to see if user has already answered interactive question
+		# If they say anything other than "yes", the boot halts, so we
+		# can just set it to true to skip asking again.
+		if [ -f /run/.boot-degraded-asked ] ; then
+			BOOT_DEGRADED="true"
+		fi
+		# Finally, prompt interactively if the user has not specified
+		# to boot degraded either in a configuration file or as a
+		# kernel boot parameter
+		if [ "$BOOT_DEGRADED" != "true" ]; then
+			txt_message '
+You may attempt to start the system anyway, or stop now and attempt
+manual recovery operations.  To do this automatically in the future,
+add "bootdegraded=true" to the kernel boot options.
+
+If you choose to start the degraded RAID, the system may boot normally,
+but performance may be degraded, and a further hardware fault could
+result in permanent data loss.
+
+If you abort now, you will be provided with a recovery shell.
+
+'
+			# Set a 15-second timeout for this question
+			ANSWER="unanswered"
+			if [ -x /bin/plymouth ] && plymouth --ping; then
+			    plymouth display-message --text="
+
+***            WARNING: Degraded RAID devices detected.            ***
+   Press Y to start the degraded RAID or N to launch recovery shell
+"
+			    ANSWER=`plymouth watch-keystroke --keys='yYnN'`
+			else
+			    read -t 15 -p "Do you wish to start the degraded RAID? [y/N]: " -r ANSWER
+			fi
+			echo "" > /run/.boot-degraded-asked
+			case "$ANSWER" in
+				unanswered) echo "Timed out" ;;
+				y*|Y*)  BOOT_DEGRADED="true" ;;
+				*)      BOOT_DEGRADED="false";;
+			esac
+		fi
+		if [ "$BOOT_DEGRADED" = "true" ]; then
+			message "Attempting to start the RAID in degraded mode..."
+			if mdadm --incremental --run --scan; then
+				message "Started the RAID in degraded mode."
+				return 0
+			else	
+				if mdadm --assemble --scan --run; then
+					message "Started the RAID in degraded mode."
+					return 0
+				else
+					message "Could not start the RAID in degraded mode."
+				fi
+			fi
+		fi
+	fi
+	return 1
+}

recipes/degraded-raid-fix.rb

@@ -0,0 +1,30 @@
+#
+# Cookbook Name:: mdadm
+# Recipe:: degraded-raid-fix
+#
+# This cookbook fixes problems on Ubuntu where the OS always
+# thinks the RAID is degraded at boot.  See below references
+# for more information.
+#
+# References:
+# http://ubuntuforums.org/showthread.php?t=1861516&page=2&p=11388915#post11388915
+# https://bugs.launchpad.net/ubuntu/+source/mdadm/+bug/872220
+# https://bugs.launchpad.net/ubuntu/+source/mdadm/+bug/990913
+# https://bugs.launchpad.net/ubuntu/+source/mdadm/+bug/917520
+#
+#
+
+cookbook_file 'mdadm-functions' do
+  path '/usr/share/initramfs-tools/scripts/mdadm-functions'
+  owner 'root'
+  group 'root'
+  mode '0755'
+  notifies :run, 'execute[update_initramfs]'
+  action :create
+end
+
+execute 'update_initramfs' do
+  command 'update-initramfs -u'
+  action :nothing
+end
+