On Tue, Nov 13, 2012 at 01:56:59PM +0900, Tomoki Sekiyama wrote: > Adds sample hook scripts for --fsfreeze-hook option of qemu-ga. > - fsfreeze-hook : execute scripts in fsfreeze-hook.d/ > - fsfreeze-hook.d.sample/mysql-flush.sh : quiesce MySQL before snapshot > > Signed-off-by: Tomoki Sekiyama <tomoki.sekiyama...@hitachi.com>
Reviewed-by: Michael Roth <mdr...@linux.vnet.ibm.com> > --- > docs/qemu-guest-agent/fsfreeze-hook | 31 +++++++++++++ > .../fsfreeze-hook.d.sample/mysql-flush.sh | 47 > ++++++++++++++++++++ > 2 files changed, 78 insertions(+) > create mode 100755 docs/qemu-guest-agent/fsfreeze-hook > create mode 100755 > docs/qemu-guest-agent/fsfreeze-hook.d.sample/mysql-flush.sh > > diff --git a/docs/qemu-guest-agent/fsfreeze-hook > b/docs/qemu-guest-agent/fsfreeze-hook > new file mode 100755 > index 0000000..319f68c > --- /dev/null > +++ b/docs/qemu-guest-agent/fsfreeze-hook > @@ -0,0 +1,31 @@ > +#!/bin/sh > + > +# This script is executed when a guest agent receives fsfreeze-freeze and > +# fsfreeze-thaw command, if it is specified in --fsfreeze-hook (-F) > +# option of qemu-ga or placed in default path (/etc/qemu/fsfreeze-hook). > +# When the agent receives fsfreeze-freeze request, this script is issued with > +# "freeze" argument before the filesystem is freezed. And for fsfreeze-thaw > +# request, it is issued with "thaw" argument after filesystem is thawed. > + > +LOGFILE=/var/log/qga-fsfreeze-hook.log > +FSFREEZE_D=$(dirname -- "$0")/fsfreeze-hook.d > + > +# Check whether file $1 is a backup or rpm-generated file and should be > ignored > +is_ignored_file() { > + case "$1" in > + *~ | *.bak | *.orig | *.rpmnew | *.rpmorig | *.rpmsave) > + return 0 ;; > + esac > + return 1 > +} > + > +# Iterate executables in directory "fsfreeze-hook.d" with the specified args > +[ ! -d "$FSFREEZE_D" ] && exit 1 > +for file in "$FSFREEZE_D"/* ; do > + is_ignored_file "$file" && continue > + [ -x "$file" ] || continue > + echo "$(date): execute $file $@" >>$LOGFILE > + "$file" "$@" >>$LOGFILE 2>&1 > + STATUS=$? > + echo "$(date): $file finished with status=$STATUS" >>$LOGFILE > +done > diff --git a/docs/qemu-guest-agent/fsfreeze-hook.d.sample/mysql-flush.sh > b/docs/qemu-guest-agent/fsfreeze-hook.d.sample/mysql-flush.sh > new file mode 100755 > index 0000000..e6d7998 > --- /dev/null > +++ b/docs/qemu-guest-agent/fsfreeze-hook.d.sample/mysql-flush.sh > @@ -0,0 +1,47 @@ > +#!/bin/sh > + > +# Flush MySQL tables to the disk before the filesystem is freezed. > +# At the same time, this keeps a read lock while the filesystem is freezed > +# in order to avoid write accesses by the other clients. > + > +MYSQL="mysql -uroot" #"-prootpassword" > +FIFO=/tmp/mysql-flush.fifo > + > +flush_and_wait() { > + printf "FLUSH TABLES WITH READ LOCK \\G\n" > + read < $FIFO > + printf "UNLOCK TABLES \\G\n" > +} > + > +case "$1" in > + freeze) > + mkfifo $FIFO || exit 1 > + flush_and_wait | $MYSQL & > + # wait until every block is flushed > + while [ "$(echo 'SHOW STATUS LIKE "Key_blocks_not_flushed"' |\ > + $MYSQL | tail -1 | cut -f 2)" -gt 0 ]; do > + sleep 1 > + done > + # for InnoDB, wait until every log is flushed > + INNODB_STATUS=$(mktemp /tmp/mysql-flush.XXXXXX) > + [ $? -ne 0 ] && exit 2 > + trap "rm -f $INNODB_STATUS" SIGINT > + while :; do > + printf "SHOW ENGINE INNODB STATUS \\G" | $MYSQL > $INNODB_STATUS > + LOG_CURRENT=$(grep 'Log sequence number' $INNODB_STATUS |\ > + tr -s ' ' | cut -d' ' -f4) > + LOG_FLUSHED=$(grep 'Log flushed up to' $INNODB_STATUS |\ > + tr -s ' ' | cut -d' ' -f5) > + [ "$LOG_CURRENT" = "$LOG_FLUSHED" ] && break > + sleep 1 > + done > + rm -f $INNODB_STATUS > + ;; > + > + thaw) > + [ ! -p $FIFO ] && exit 1 > + echo > $FIFO > + rm -f $FIFO > + ;; > +esac > + >