1. Intensively talk about 05-if conditions
Single branch structure syntax:
if [ 条件 ];then
指令
fi
Multi-branch structure syntax:
if 条件
then
指令
elif 条件
then
指令
else
指令
fi
Determine whether the parameter is an integer number
#judge num
[ -n "`echo $1|sed 's/[0-9]//g'`" -a -n "`echo $2|sed 's/[0-9]//g'`"] &&\
echo "两个参数都必须为数字" && exit
if [-n str1] is true when the length of the string is greater than 0 (the string is not empty). If it is a number, sed is replaced by a null value.
Check to determine whether the mysql service exists
MYUSER=root
MYPASS="oldboy"
MYSOCK=/data/3306/mysql.sock
MySQL_STARTUP="/data/3306/mysql"
LOG_PATH=/tmp
LOG_FILE=${LOG_PATH}/mysqllogs_`date +%F`.log
MYSQL_PATH=/usr/local/mysql/bin
MYSQL_CMD="$MYSQL_PATH/mysql -u$MYUSER -p$MYPASS -S $MYSOCK"
$MYSQL_CMD -e "select version();" >/dev/null 2>&1
if [ $? -eq 0 ]
then
echo "MySQL is running! "
exit 0
else
$MySQL_STARTUP start >$LOG_FILE
sleep 5;
$MYSQL_CMD -e "select version();" >/dev/null 2>&1
if [ $? -ne 0 ]
then
#通过for循环来杀mysqld ，然后启动mysqld
for num in `seq 5`
do
killall mysqld >/dev/null 2>&1
[ $? -ne 0 ] && break;
sleep 1
done
$MySQL_STARTUP start >>$LOG_FILE
fi
$MYSQL_CMD -e "select version();" >/dev/null 2>&1 && Status="restarted" || Status="unknown"
mail -s "MySQL status is $Status" [email protected] < $LOG_FILE #将上面的Status发到邮箱
fi
exit $RETVAL
Monitor apache service (check port, process and URL at the same time)
#先加载 /etc/init.d/functions 可参考https://www.cnblogs.com/sunfie/p/5149678.html
. /etc/init.d/functions
LOG_FILE=/tmp/httpd.log
apachectl="/application/apache/bin/apachectl"
HTTPPORTNUM=`netstat -lnt|grep 80|grep -v grep|wc -l`
HTTPPRONUM=`ps -ef|grep http|grep -v grep|wc -l`
#使用 wget –spider 测试下载链接 ,如果下载链接正确，将会显示内容
#可参考https://www.cnblogs.com/sx66/p/11887022.html
wget --quiet --spider http://10.0.0.179:8000 && RETVAL=$?
#以上变量要事先调试正确后 在放到脚本运行
[ ! -f $LOG_FILE ] && touch $LOG_FILE
#不正常情况的判断
if [ "$RETVAL" != "0" -o "$HTTPPORTNUM" -lt "1" -o "$HTTPPRONUM" \< "1" ] ;then
#echo $RETVAL $HTTPPORTNUM $HTTPPRONUM
#exit
action "httpd is not running" /bin/false
echo -e "httpd is not running\n" >$LOG_FILE
#杀进程，然后启动
echo "Preparing start apache..."
for num in `seq 10`
do
killall httpd >/dev/null 2>&1
[ $? -ne 0 ] && {
echo "httpd is killed" >$LOG_FILE
break;
}
sleep 2
done
$apachectl start >/dev/null 2>&1 && Status="started" || Status="unknown"
[ "$Status" = "started" ] && action "httpd is started" /bin/true||\
action "httpd is started" /bin/false
mail -s "`uname -n`'s httpd status is $Status" [email protected] <$LOG_FILE
exit
else
action "httpd is running" /bin/true
exit 0
fi
Monitor whether a port is normal
ip_add="$1"
port="$2"
print_usage(){
echo -e "$0 ip port"
exit 1
}
#judge para num
if [ $# -ne 2 ]
then
print_usage
fi
#使用nmap 来对端口进行扫描
PORT_COUNT=`nmap $ip_add -p $port|grep open|wc -l`
#echo -e "\n" |telnet $ip_add $port||grep Connected
#echo -e "\n"|telnet 10.0.0.179 8000|grep Connected
[[ $PORT_COUNT -ge 1 ]] && echo "$ip_add $port is ok." || echo "$ip_add $port is unknown."
2. Explain the 06-case conditions in detail
case structure conditional grammar
case "字符串" in
值1) 指令...
;;
值1) 指令...
;;
*) 指令...
esac
Start/stop/restart the apache script (use case)
These two files are the same, in fact one is a soft link
#关闭apache
/appilication/apache/bin/httpd -k stop
#开启apache
/appilication/apache/bin/httpd -k start
#!/bin/bash
# Source function library.
[ -f /etc/rc.d/init.d/functions ] && . /etc/rc.d/init.d/functions
RETVAL=0
httpd="/application/apache/bin/httpd"
start() {
$httpd -k start >/dev/null 2>&1
RETVAL=$?
[ $RETVAL -eq 0 ] && action "启动 httpd:" /bin/true ||\
action "启动 httpd:" /bin/false
return $RETVAL
}
stop() {
$httpd -k stop >/dev/null 2>&1
[ $? -eq 0 ] && action "停止 httpd:" /bin/true ||\
action "停止 httpd:" /bin/false
return $RETVAL
}
case "$1" in
start)
start
;;
stop)
stop
;;
restart)
sh $0 stop
sh $0 start
;;
*)
echo "Format error!"
echo $"Usage: $0 {start|stop|restart}"
exit 1
;;
esac
exit $RETVAL
3. Intensively talk about 07-while loop
While conditional sentence syntax:
while 条件
do
指令
done
Knowledge of background execution of scripts
Check the status of the website url
#!/bin/bash
. /etc/init.d/functions
#将要检测的url放到数组中
url_list=(
https://www.baidu.com/
https://www.qq.com/
https://www.4399.com/
)
function wait()
{
echo -n '3秒后,执行该操作.';
for ((i=0;i<3;i++))
do
echo -n ".";sleep 1
done
echo
}
function check_url()
{
wait
echo 'check url...'
for ((i=0; i<`echo ${#url_list[*]}`; i++))
do
#结果为 HTTP/1.1 200 OK 目前只是检测200状态的，没添加重定向301、302的判断
#if [[ "${judge[1]}" == '200' || "${judge[1]}" == '301' && "${judge[2]}"=='OK' ]]
judge=($(curl -I -s ${
url_list[$i]}|head -1|tr "\r" "\n"))
if [[ "${judge[1]}" == '200' && "${judge[2]}"=='OK' ]]
then
action "${url_list[$i]}" /bin/true
else
action "${url_list[$i]}" /bin/false
fi
done
}
check_url
Calculate the sum of the number of access bytes of each log element of all lines in the apache log access_2010-12-8.log for a day.
Log content:
59.33.26.105 - - [08/Dec/2010:15:43:55 +0800] "GET //back/upload/course/2010-10-25-23-48-59-048-18.jpg HTTP/1.1" 200 44286 "http://oldboy.blog.51cto.com/static/web/column/17/index.shtml?courseId=43" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)"
59.33.26.105 - - [08/Dec/2010:15:43:55 +0800] "GET /back/upload/teacher/2010-08-06-11-39-59-0469.jpg HTTP/1.1" 200 10850 "http://oldboy.blog.51cto.com/static/web/column/17/index.shtml?courseId=43" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)"
59.33.26.105 - - [08/Dec/2010:15:43:55 +0800] "GET /back/upload/teacher/2010-08-30-13-57-43-06210.jpg HTTP/1.1" 200 11809 "http://oldboy.blog.51cto.com/static/web/column/17/index.shtml?courseId=43" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)"
59.33.26.105 - - [08/Dec/2010:15:43:55 +0800] "GET /static/web/coursesort/5.shtml HTTP/1.1" 200 255 "http://oldboy.blog.51cto.com/static/web/column/17/index.shtml?courseId=43" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)"
59.33.26.105 - - [08/Dec/2010:15:43:55 +0800] "POST /cms/cmtweb!getCommentListBySource.action HTTP/1.1" 200 433 "http://oldboy.blog.51cto.com/static/web/column/17/index.shtml?courseId=43" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)"
59.33.26.105 - - [08/Dec/2010:15:43:56 +0800] "GET /static/images/photos/2.jpg HTTP/1.1" 200 11299 "http://oldboy.blog.51cto.com/static/web/column/17/index.shtml?courseId=43" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)"
59.33.26.105 - - [08/Dec/2010:15:43:56 +0800] "GET /static/images/photos/2.jpg HTTP/1.1" 200 11299 "http://oldboy.blog.51cto.com/static/web/column/17/index.shtml?courseId=43" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)"
59.33.26.105 - - [08/Dec/2010:15:43:56 +0800] "GET /static/images/photos/2.jpg HTTP/1.1" 200 11299 "http://oldboy.blog.51cto.com/static/web/column/17/index.shtml?courseId=43" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)"
59.33.26.105 - - [08/Dec/2010:15:44:02 +0800] "GET /static/flex/vedioLoading.swf HTTP/1.1" 200 3583 "http://oldboy.blog.51cto.com/static/flex/AdobeVideoPlayer.swf?width=590&height=328&url=/[[DYNAMIC]]/2" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)"
124.115.4.18 - - [08/Dec/2010:15:44:15 +0800] "GET /?= HTTP/1.1" 200 46232 "-" "-"
124.115.4.18 - - [08/Dec/2010:15:44:25 +0800] "GET /static/js/web_js.js HTTP/1.1" 200 4460 "-" "-"
124.115.4.18 - - [08/Dec/2010:15:44:25 +0800] "GET /static/js/jquery.lazyload.js HTTP/1.1" 200 1627 "-" "-"
124.115.4.18 - - [08/Dec/2010:15:44:25 +0800] "GET /static/js/common.js HTTP/1.1" 200 1861 "-" "-"
124.115.4.18 - - [08/Dec/2010:15:44:25 +0800] "GET /static/js/default.js HTTP/1.1" 200 2686 "-" "-"
124.115.4.18 - - [08/Dec/2010:15:44:25 +0800] "GET /static/js/cookieUtil.js HTTP/1.1" 200 955 "-" "-"
124.115.4.18 - - [08/Dec/2010:15:44:25 +0800] "GET /static/js/jquery-jquery-1.3.2.min.js HTTP/1.1" 200 57254 "-" "-"
124.115.4.18 - - [08/Dec/2010:15:44:26 +0800] "GET /static/js/addToCart.js HTTP/1.1" 200 6417 "-" "-"
123.122.65.226 - - [08/Dec/2010:15:44:43 +0800] "GET /static/flex/vedioLoading.swf HTTP/1.1" 304 - "http://oldboy.blog.51cto.com/static/flex/VideoCenter.swf?url=/[[DYNAMIC]]/2" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)"
123.122.65.226 - - [08/Dec/2010:15:44:43 +0800] "POST /messagebroker/amf HTTP/1.1" 200 183 "http://oldboy.blog.51cto.com/static/flex/VideoCenter.swf?url=/[[DYNAMIC]]/4" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)"
123.122.65.226 - - [08/Dec/2010:15:44:43 +0800] "POST /messagebroker/amf HTTP/1.1" 200 117 "http://oldboy.blog.51cto.com/static/flex/VideoCenter.swf?url=/[[DYNAMIC]]/4" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)"
exec <$1
sum=0
while read line
do
num=`echo $line|awk '{print $10}'`
[ -n "$num" -a "$num" = "${num//[^0-9]/}" ] || continue
((sum=sum+$num))
done
echo "${1}:${sum} bytes =`echo $((${
sum}/1024))`KB"
END