Init script for handling guests on shutdown/boot

Example output during shutdown:

Running guests on default URI: console, rhel6-1, rhel5-64
Running guests on lxc:/// URI: lxc-shell
Running guests on xen:/// URI: error: no hypervisor driver available for xen:///
error: failed to connect to the hypervisor
Running guests on vbox+tcp://orkuz/system URI: no running guests.
Suspending guests on default URI...
Suspending console: done
Suspending rhel6-1: done
Suspending rhel5-64: done
Suspending guests on lxc:/// URI...
Suspending lxc-shell: error: Failed to save domain 9cba8bfb-56f4-6589-2d12-8a58c886dd3b state
error: this function is not supported by the hypervisor: virDomainManagedSave

Note, the "Suspending $guest: " shows progress during the suspend phase
if domjobinfo gives meaningful output.

Example output during boot:

Resuming guests on default URI...
Resuming guest rhel6-1: done
Resuming guest rhel5-64: done
Resuming guest console: done
Resuming guests on lxc:/// URI...
Resuming guest lxc-shell: already active

Configuration used for generating the examples above:
URIS='default lxc:/// xen:/// vbox+tcp://orkuz/system'

The script uses /var/lib/libvirt/libvirt-guests files to note all active
guest it should try to resume on next boot. It's content looks like:

default 7f8b9d93-30e1-f0b9-47a7-cb408482654b 085b4c95-5da2-e8e1-712f-6ea6a4156af2 fb4d8360-5305-df3a-2da1-07d682891b8c
lxc:/// 9cba8bfb-56f4-6589-2d12-8a58c886dd3b

daemon/Makefile.am

@@ -30,6 +30,8 @@ EXTRA_DIST =						\
 	libvirtd.uml.logrotate.in                       \
 	test_libvirtd.aug                               \
 	THREADING.txt					\
+	libvirt-guests.init.in				\
+	libvirt-guests.sysconf				\
 	$(AVAHI_SOURCES)				\
 	$(DAEMON_SOURCES)
 
@@ -217,21 +219,27 @@ install-logrotate: $(LOGROTATE_CONFS)
 	$(INSTALL_DATA) libvirtd.uml.logrotate $(DESTDIR)$(sysconfdir)/logrotate.d/libvirtd.uml
 
 if LIBVIRT_INIT_SCRIPT_RED_HAT
-install-init: libvirtd.init
+install-init: libvirtd.init libvirt-guests.init
 	mkdir -p $(DESTDIR)$(sysconfdir)/rc.d/init.d
 	$(INSTALL_SCRIPT) libvirtd.init \
 	  $(DESTDIR)$(sysconfdir)/rc.d/init.d/libvirtd
+	$(INSTALL_SCRIPT) libvirt-guests.init \
+	  $(DESTDIR)$(sysconfdir)/rc.d/init.d/libvirt-guests
 	mkdir -p $(DESTDIR)$(sysconfdir)/sysconfig
 	$(INSTALL_SCRIPT) $(srcdir)/libvirtd.sysconf \
 	  $(DESTDIR)$(sysconfdir)/sysconfig/libvirtd
+	$(INSTALL_SCRIPT) $(srcdir)/libvirt-guests.sysconf \
+	  $(DESTDIR)$(sysconfdir)/sysconfig/libvirt-guests
 
 uninstall-init:
 	rm -f $(DESTDIR)$(sysconfdir)/rc.d/init.d/libvirtd \
-		$(DESTDIR)$(sysconfdir)/sysconfig/libvirtd
+		$(DESTDIR)$(sysconfdir)/sysconfig/libvirtd \
+		$(DESTDIR)$(sysconfdir)/rc.d/init.d/libvirt-guests \
+		$(DESTDIR)$(sysconfdir)/sysconfig/libvirt-guests
 
-BUILT_SOURCES += libvirtd.init
+BUILT_SOURCES += libvirtd.init libvirt-guests.init
 
-libvirtd.init: libvirtd.init.in
+%.init: %.init.in
 	$(AM_V_GEN)sed					\
 	    -e s!\@localstatedir\@!@localstatedir@!g	\
 	    -e s!\@sbindir\@!@sbindir@!g		\

daemon/libvirt-guests.init.in

+#!/bin/sh
+
+# the following is the LSB init header
+#
+### BEGIN INIT INFO
+# Provides: libvirt-guests
+# Required-Start: libvirtd
+# Required-Stop: libvirtd
+# Default-Start: 3 4 5
+# Short-Description: suspend/resume libvirt guests on shutdown/boot
+# Description: This is a script for suspending active libvirt guests
+#              on shutdown and resuming them on next boot
+#              See http://libvirt.org
+### END INIT INFO
+
+# the following is chkconfig init header
+#
+# libvirt-guests:   suspend/resume libvirt guests on shutdown/boot
+#
+# chkconfig: 345 98 02
+# description:  This is a script for suspending active libvirt guests \
+#               on shutdown and resuming them on next boot \
+#               See http://libvirt.org
+#
+
+sysconfdir=@sysconfdir@
+localstatedir=@localstatedir@
+
+# Source function library.
+. "$sysconfdir"/rc.d/init.d/functions
+
+URIS=default
+ON_BOOT=start
+ON_SHUTDOWN=suspend
+SHUTDOWN_TIMEOUT=0
+
+test -f "$sysconfdir"/sysconfig/libvirt-guests && . "$sysconfdir"/sysconfig/libvirt-guests
+
+LISTFILE="$localstatedir"/lib/libvirt/libvirt-guests
+
+RETVAL=0
+
+retval() {
+    "$@"
+    if [ $? -ne 0 ]; then
+        RETVAL=1
+        return 1
+    else
+        return 0
+    fi
+}
+
+run_virsh() {
+    uri=$1
+    shift
+
+    if [ "x$uri" = xdefault ]; then
+        conn=
+    else
+        conn="-c $uri"
+    fi
+
+    virsh $conn "$@"
+}
+
+run_virsh_c() {
+    ( export LC_ALL=C; run_virsh "$@" )
+}
+
+list_guests() {
+    uri=$1
+
+    list=$(run_virsh_c $uri list)
+    if [ $? -ne 0 ]; then
+        RETVAL=1
+        return 1
+    fi
+
+    uuids=
+    for id in $(echo "$list" | awk 'NR > 2 {print $1}'); do
+        uuid=$(run_virsh_c $uri dominfo $id | awk '/^UUID:/{print $2}')
+        if [ -z "$uuid" ]; then
+            RETVAL=1
+            return 1
+        fi
+        uuids="$uuids $uuid"
+    done
+
+    echo $uuids
+}
+
+guest_name() {
+    uri=$1
+    uuid=$2
+
+    name=$(run_virsh_c $uri dominfo $uuid 2>/dev/null | \
+           awk '/^Name:/{print $2}')
+    [ -n "$name" ] || name=$uuid
+
+    echo "$name"
+}
+
+guest_is_on() {
+    uri=$1
+    uuid=$2
+
+    guest_running=false
+    info=$(run_virsh_c $uri dominfo $uuid)
+    if [ $? -ne 0 ]; then
+        RETVAL=1
+        return 1
+    fi
+
+    id=$(echo "$info" | awk '/^Id:/{print $2}')
+
+    [ -n "$id" ] && [ "x$id" != x- ] && guest_running=true
+    return 0
+}
+
+start() {
+    [ -f $LISTFILE ] || return 0
+
+    if [ "x$ON_BOOT" != xstart ]; then
+        echo $"libvirt-guests is configured not to start any guests on boot"
+        rm -f $LISTFILE
+        return 0
+    fi
+
+    while read uri list; do
+        configured=false
+        for confuri in $URIS; do
+            if [ $confuri = $uri ]; then
+                configured=true
+                break
+            fi
+        done
+        if ! $configured; then
+            echo $"Ignoring guests on $uri URI"
+            continue
+        fi
+
+        echo $"Resuming guests on $uri URI..."
+        for guest in $list; do
+            name=$(guest_name $uri $guest)
+            echo -n $"Resuming guest $name: "
+            if guest_is_on $uri $guest; then
+                if $guest_running; then
+                    echo $"already active"
+                else
+                    retval run_virsh $uri start "$name" >/dev/null && \
+                    echo $"done"
+                fi
+            fi
+        done
+    done <$LISTFILE
+
+    rm -f $LISTFILE
+}
+
+suspend_guest()
+{
+    uri=$1
+    guest=$2
+
+    name=$(guest_name $uri $guest)
+    label=$"Suspending $name: "
+    echo -n "$label"
+    run_virsh $uri managedsave $guest >/dev/null &
+    virsh_pid=$!
+    while true; do
+        sleep 1
+        kill -0 $virsh_pid >&/dev/null || break
+        progress=$(run_virsh_c $uri domjobinfo $guest 2>/dev/null | \
+                   awk '/^Data processed:/{print $3, $4}')
+        if [ -n "$progress" ]; then
+            printf '\r%s%12s ' "$label" "$progress"
+        else
+            printf '\r%s%-12s ' "$label" "..."
+        fi
+    done
+    retval wait $virsh_pid && printf '\r%s%-12s\n' "$label" $"done"
+}
+
+shutdown_guest()
+{
+    uri=$1
+    guest=$2
+
+    name=$(guest_name $uri $guest)
+    label=$"Shutting down $name: "
+    echo -n "$label"
+    retval run_virsh $uri shutdown $guest >/dev/null || return
+    timeout=$SHUTDOWN_TIMEOUT
+    while [ $timeout -gt 0 ]; do
+        sleep 1
+        timeout=$[timeout - 1]
+        guest_is_on $uri $guest || return
+        $guest_running || break
+        printf '\r%s%-12d ' "$label" $timeout
+    done
+
+    if guest_is_on $uri $guest; then
+        if $guest_running; then
+            printf '\r%s%-12s\n' "$label" $"failed to shutdown in time"
+        else
+            printf '\r%s%-12s\n' "$label" $"done"
+        fi
+    fi
+}
+
+stop() {
+    # last stop was not followed by start
+    [ -f $LISTFILE ] && return 0
+
+    suspending=true
+    if [ "x$ON_SHUTDOWN" = xshutdown ]; then
+        suspending=false
+        if [ $SHUTDOWN_TIMEOUT -le 0 ]; then
+            echo $"Shutdown action requested but SHUTDOWN_TIMEOUT was not set"
+            RETVAL=6
+            return
+        fi
+    fi
+
+    : >$LISTFILE
+    for uri in $URIS; do
+        echo -n $"Running guests on $uri URI: "
+        list=$(list_guests $uri)
+        if [ $? -eq 0 ]; then
+            empty=true
+            for uuid in $list; do
+                $empty || printf ", "
+                echo -n $(guest_name $uri $uuid)
+                empty=false
+            done
+            if $empty; then
+                echo $"no running guests."
+            else
+                echo
+                echo $uri $list >>$LISTFILE
+            fi
+        fi
+    done
+
+    while read uri list; do
+        if $suspending; then
+            echo $"Suspending guests on $uri URI..."
+        else
+            echo $"Shutting down guests on $uri URI..."
+        fi
+
+        for guest in $list; do
+            if $suspending; then
+                suspend_guest $uri $guest
+            else
+                shutdown_guest $uri $guest
+            fi
+        done
+    done <$LISTFILE
+}
+
+gueststatus() {
+    for uri in $URIS; do
+        echo "* $uri URI:"
+        retval run_virsh $uri list || echo
+    done
+}
+
+# See how we were called.
+case "$1" in
+    start|stop|gueststatus)
+        $1
+        ;;
+    restart)
+        stop && start
+        ;;
+    force-reload)
+        ;;
+    status)
+        if [ -f $LISTFILE ]; then
+            RETVAL=3
+        else
+            RETVAL=0
+        fi
+        ;;
+    shutdown)
+        ON_SHUTDOWN=shutdown
+        stop
+        ;;
+    *)
+        echo $"Usage: $0 {start|stop|restart|force-reload|gueststatus|shutdown}"
+        exit 3
+        ;;
+esac
+exit $RETVAL

daemon/libvirt-guests.sysconf

+# URIs to check for running guests
+# example: URIS='default xen:/// vbox+tcp://host/system lxc:///'
+#URIS=default
+
+# action taken on host boot
+# - start   all guests which were running on shutdown are started on boot
+#           regardless on their autostart settings
+# - ignore  libvirt-guests init script won't start any guest on boot, however,
+#           guests marked as autostart will still be automatically started by
+#           libvirtd
+#ON_BOOT=start
+
+# action taken on host shutdown
+# - suspend   all running guests are suspended using virsh managedsave
+# - shutdown  all running guests are asked to shutdown. Please be careful with
+#             this settings since there is no way to distinguish between a
+#             guest which is stuck or ignores shutdown requests and a guest
+#             which just needs a long time to shutdown. When setting
+#             ON_SHUTDOWN=shutdown, you must also set SHUTDOWN_TIMEOUT to a
+#             value suitable for your guests.
+#ON_SHUTDOWN=suspend
+
+# number of seconds we're willing to wait for a guest to shut down
+#SHUTDOWN_TIMEOUT=0

libvirt.spec.in

@@ -830,6 +830,10 @@ fi
 
 %{_datadir}/libvirt/cpu_map.xml
 
+%{_sysconfdir}/rc.d/init.d/libvirt-guests
+%config(noreplace) %{_sysconfdir}/sysconfig/libvirt-guests
+%dir %attr(0700, root, root) %{_localstatedir}/lib/libvirt
+
 %if %{with_sasl}
 %config(noreplace) %{_sysconfdir}/sasl2/libvirt.conf
 %endif