1蒸苇、顯示統(tǒng)計占用系統(tǒng)內(nèi)存最多的進(jìn)程，并排序吮旅。
使用top命令顯示系統(tǒng)資源使用情況溪烤，按M依照內(nèi)存使用情況排序味咳。
image.png
2、編寫腳本檬嘀，使用for和while分別實現(xiàn)192.168.0.0/24網(wǎng)段內(nèi)槽驶，地址是否能夠ping通，若ping通則輸出"success!"鸳兽，若ping不通則輸出"fail!"
for循環(huán)
[root@localhost scripts]# vim for_ping.sh
for i in {1..254};do
{
if ping -W1 -c1 $NETID$i &> /dev/null;then
echo ping:$NETID$i successs!
else
echo ping:$NETID$i fail
fi
}
done
wait
[root@localhost scripts]# bash -n for_ping.sh
[root@localhost scripts]# chmod +x for_ping.sh
[root@localhost scripts]# ./for_ping.sh
ping:192.168.0.1 fail
ping:192.168.0.2 fail
ping:192.168.0.3 fail
ping:192.168.0.4 fail
ping:192.168.0.5 fail
ping:192.168.0.6 fail
ping:192.168.0.7 fail
ping:192.168.0.8 fail
ping:192.168.0.9 fail
ping:192.168.0.10 fail
ping:192.168.0.11 fail
ping:192.168.0.12 fail
ping:192.168.0.13 fail
ping:192.168.0.14 fail
ping:192.168.0.15 fail
ping:192.168.0.16 fail
ping:192.168.0.17 fail
ping:192.168.0.18 fail
ping:192.168.0.19 fail
ping:192.168.0.20 fail
······ //以下輸出省略
while循環(huán)
[root@localhost scripts]# vim while_ping.sh
NETID=192.168.0
i=1
while [ $i -lt 255 ];do
{
if ping -W1 -c1 $NETID.$i &> /dev/null;then
echo ping:$NETID.$i success!
else
echo ping:$NETID.$i fail
fi
}
done
wait
[root@localhost scripts]# bash -n while_ping.sh
[root@localhost scripts]# chmod +x while_ping.sh
[root@localhost scripts]# ./while_ping.sh
ping:192.168.0.1 fail
ping:192.168.0.2 fail
ping:192.168.0.3 fail
ping:192.168.0.4 fail
ping:192.168.0.5 fail
ping:192.168.0.6 fail
ping:192.168.0.7 fail
ping:192.168.0.8 fail
ping:192.168.0.9 fail
ping:192.168.0.10 fail
ping:192.168.0.11 fail
ping:192.168.0.12 fail
ping:192.168.0.13 fail
ping:192.168.0.14 fail
ping:192.168.0.15 fail
ping:192.168.0.16 fail
ping:192.168.0.17 fail
ping:192.168.0.18 fail
······ //以下輸出省略
3掂铐、每周的工作日1:30，將/etc備份至/backup目錄中揍异，保存的文件名稱格式 為“etcbak-yyyy-mm-dd-HH.tar.xz”全陨，其中日期是前一天的時間
[root@localhost scripts]# vim bakup.sh
BACKNAME=etcbak-`date -d -1day +%F-%H`
tar -Jcvf /backup/${BACKNAME}.tar.xz /etc &> /dev/null
[root@localhost scripts]# bash -n bakup.sh
[root@localhost scripts]# chmod +x bakup.sh
[root@localhost scripts]# crontab -e
30 13 * * 1-5 /usr/bin/bash /data/scripts/bakup.sh
[root@localhost scripts]# ./bakup.sh
[root@localhost scripts]#
[root@localhost scripts]# echo $?
0
[root@localhost scripts]# ll /backup/
total 7640
-rw-r--r--. 1 root root 7822328 Aug 10 21:28 etcbak-2020-08-09-21.tar.xz
4、工作日時間衷掷，每10分鐘執(zhí)行一次磁盤空間檢查辱姨，一旦發(fā)現(xiàn)任何分區(qū)利用率高 于80%，就發(fā)送郵件報警
[root@localhost scripts]# vim checkdisk.sh
USED=`df -h|awk -F " +|%" '/^\/dev\/sd.*/{print $5}'|sort -nr|head -1`
if [ $USED -gt 80 ];then
mail root << eof
someone disk used more than 80%,please check!
eof
fi
[root@localhost scripts]# bash -n checkdisk.sh
[root@localhost scripts]# chmod +x checkdisk.sh
[root@localhost scripts]# crontab -e
30 13 * * 1-5 /usr/bin/bash /data/scripts/bakup.sh
*/10 * * * 1-5 /usr/bin/bash /data/scripts/diskcheck.sh
