From 96610da210697a1f33669d8bec0cb7b944d3a516 Mon Sep 17 00:00:00 2001 From: Tomoki Sekiyama Date: Wed, 12 Dec 2012 12:55:57 +0900 Subject: qemu-ga: sample fsfreeze hooks Adds sample hook scripts for --fsfreeze-hook option of qemu-ga. - fsfreeze-hook : execute scripts in fsfreeze-hook.d/ - fsfreeze-hook.d/mysql-flush.sh.sample : quiesce MySQL before snapshot Signed-off-by: Tomoki Sekiyama Reviewed-by: Michael Roth Signed-off-by: Michael Roth --- scripts/qemu-guest-agent/fsfreeze-hook | 33 +++++++++++++ .../fsfreeze-hook.d/mysql-flush.sh.sample | 56 ++++++++++++++++++++++ 2 files changed, 89 insertions(+) create mode 100755 scripts/qemu-guest-agent/fsfreeze-hook create mode 100755 scripts/qemu-guest-agent/fsfreeze-hook.d/mysql-flush.sh.sample (limited to 'scripts/qemu-guest-agent') diff --git a/scripts/qemu-guest-agent/fsfreeze-hook b/scripts/qemu-guest-agent/fsfreeze-hook new file mode 100755 index 0000000000..c27b29f282 --- /dev/null +++ b/scripts/qemu-guest-agent/fsfreeze-hook @@ -0,0 +1,33 @@ +#!/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 frozen. 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 "$1" in + *~ | *.bak | *.orig | *.rpmnew | *.rpmorig | *.rpmsave | *.sample) + return 0 ;; + esac + return 1 +} + +# Iterate executables in directory "fsfreeze-hook.d" with the specified args +[ ! -d "$FSFREEZE_D" ] && exit 0 +for file in "$FSFREEZE_D"/* ; do + is_ignored_file "$file" && continue + [ -x "$file" ] || continue + printf "$(date): execute $file $@\n" >>$LOGFILE + "$file" "$@" >>$LOGFILE 2>&1 + STATUS=$? + printf "$(date): $file finished with status=$STATUS\n" >>$LOGFILE +done + +exit 0 diff --git a/scripts/qemu-guest-agent/fsfreeze-hook.d/mysql-flush.sh.sample b/scripts/qemu-guest-agent/fsfreeze-hook.d/mysql-flush.sh.sample new file mode 100755 index 0000000000..2b4fa3aeb1 --- /dev/null +++ b/scripts/qemu-guest-agent/fsfreeze-hook.d/mysql-flush.sh.sample @@ -0,0 +1,56 @@ +#!/bin/sh + +# Flush MySQL tables to the disk before the filesystem is frozen. +# At the same time, this keeps a read lock in order to avoid write accesses +# from the other clients until the filesystem is thawed. + +MYSQL="/usr/bin/mysql" +MYSQL_OPTS="-uroot" #"-prootpassword" +FIFO=/var/run/mysql-flush.fifo + +# Check mysql is installed and the server running +[ -x "$MYSQL" ] && "$MYSQL" $MYSQL_OPTS < /dev/null || exit 0 + +flush_and_wait() { + printf "FLUSH TABLES WITH READ LOCK \\G\n" + trap 'printf "$(date): $0 is killed\n">&2' HUP INT QUIT ALRM TERM + read < $FIFO + printf "UNLOCK TABLES \\G\n" + rm -f $FIFO +} + +case "$1" in + freeze) + mkfifo $FIFO || exit 1 + flush_and_wait | "$MYSQL" $MYSQL_OPTS & + # wait until every block is flushed + while [ "$(echo 'SHOW STATUS LIKE "Key_blocks_not_flushed"' |\ + "$MYSQL" $MYSQL_OPTS | tail -1 | cut -f 2)" -gt 0 ]; do + sleep 1 + done + # for InnoDB, wait until every log is flushed + INNODB_STATUS=$(mktemp /tmp/mysql-flush.XXXXXX) + [ $? -ne 0 ] && exit 2 + trap "rm -f $INNODB_STATUS; exit 1" HUP INT QUIT ALRM TERM + while :; do + printf "SHOW ENGINE INNODB STATUS \\G" |\ + "$MYSQL" $MYSQL_OPTS > $INNODB_STATUS + LOG_CURRENT=$(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 + ;; + + *) + exit 1 + ;; +esac -- cgit v1.2.3