Cronから実行するEC2スナップショットスクリプト

実行条件

• awscliがインストールされている
• IAMロールなどでEC2周りの権限を解放しておく

スクリプト

#!/bin/sh

#　取得したいインスタンスのidを並べる
INSTANCE_ID=(i-xxxxx1 i-xxxxx2 i-xxxxx3)

SHELLDIR=`dirname ${0}`
SHELLDIR=`cd ${SHELLDIR}; pwd`
SHELLNAME=`basename $0`

LOG_DIR="/var/log"
LOG_SAVE_PERIOD=14
LOG_FILE="${LOG_DIR}/${SHELLNAME}.log"
echo $LOG_FILE

REGION=ca-central-1
SNAPSHOTS_PERIOD=2

AWS="/usr/bin/aws --region ${REGION}"


rotate_log() {
    (( cnt=${LOG_SAVE_PERIOD} ))
    while (( cnt > 0 ))
    do
        logfile1=${LOG_FILE}.$cnt
        (( cnt=cnt-1 ))
        logfile2=${LOG_FILE}.$cnt
        if [ -f $logfile2 ]; then
            mv $logfile2 $logfile1
        fi
    done

    if [ -f $LOG_FILE ]; then
        mv ${LOG_FILE} ${LOG_FILE}.1
    fi
    touch $LOG_FILE
}

print_msg() {
    echo "`date '+%Y/%m/%d %H:%M:%S'` $1" | tee -a ${LOG_FILE}
}

create_snapshot() {
    for ID in `echo $@`
    do
        print_msg "Create snapshot Start"
        VOL_ID=`${AWS} ec2 describe-instances --instance-ids ${ID} --output text | grep EBS | awk '{print $5}'`
        if [ -z ${VOL_ID} ] ; then
            echo ${VOL_ID}
            print_msg "ERR:ec2-describe-instances"
            logger -f ${LOG_FILE}
            exit 1
        fi
        print_msg "ec2-describe-instances Success : ${VOL_ID}"
        ${AWS} ec2 create-snapshot --volume-id ${VOL_ID} --description "Created by SYSTEMBK(${ID}) from ${VOL_ID}" >> ${LOG_FILE} 2>&1
        if [ $? != 0 ] ; then
            print_msg "ERR:${SHELLDIR}/${SHELLNAME} ec2-create-snapshot"
            logger -f ${LOG_FILE}
            exit 1
        fi
        print_msg "Create snapshot End"
    done
}

delete_old_snapshot() {
    for ID in `echo $@`
    do
        VOL_ID=`${AWS} ec2 describe-instances --instance-ids ${ID} --output text | grep EBS | awk '{print $5}'`
        print_msg "Delete old snapshot Start"
        SNAPSHOTS=`${AWS} ec2 describe-snapshots --output text | grep ${VOL_ID} | grep "Created by SYSTEMBK" | wc -l`
        while [ ${SNAPSHOTS} -gt ${SNAPSHOTS_PERIOD} ]
        do
            ${AWS} ec2 delete-snapshot --snapshot-id `${AWS} ec2 describe-snapshots --output text | grep ${VOL_ID} | grep "Created by SYSTEMBK" | sort -k 11,11 | awk 'NR==1 {print $10}'` >> ${LOG_FILE} 2>&1
            if [ $? != 0 ] ; then
                print_msg "ERR:${SHELLDIR}/${SHELLNAME} ec2-delete-snapshot"
                logger -f ${LOG_FILE}
                exit 1
            fi
            SNAPSHOTS=`${AWS} ec2 describe-snapshots | grep ${VOL_ID} | grep "Created by SYSTEMBK" | wc -l`
        done
        print_msg "Delete old snapshot End"
    done
}

rotate_log

print_msg "INF:$SHELLDIR/${SHELLNAME} START"
create_snapshot ${INSTANCE_ID[@]}
delete_old_snapshot ${INSTANCE_ID[@]}
print_msg "INF:$SHELLDIR/${SHELLNAME} END"

exit 0