1、复制/etc/skel目录为/home/tuser1,要求/home/tuser1及其内部文件的属组和其它用户均没有任何访问权限。
[[email protected] ~]# cp -a /etc/skel/ /home/tuser1 [[email protected] ~]# chmod -R 700 /home/tuser1/ [[email protected] ~]# ll -d !$ ll -d /home/tuser1/ drwx------ 3 root root 4096 2015-03-27 /home/tuser1/
2、编辑/etc/group文件,添加组hadoop。
[[email protected] ~]# echo "hadoop:x:3000" >> /etc/group [[email protected] ~]# tail -1 !$ tail -1 /etc/group hadoop:x:3000
3、手动编辑/etc/passwd文件新增一行,添加用户hadoop,其基本组ID为hadoop组的id号;其家目录为/home/hadoop。
[[email protected] ~]# echo hadoop:x:3000:3000:hadoop:/home/hadoop:/bin/bash >> /etc/passwd[[email protected] ~]# tail -1 !$ tail -1 /etc/passwd hadoop:x:3000:3000:hadoop:/home/hadoop:/bin/bash
4、复制/etc/skel目录为/home/hadoop,要求修改hadoop目录的属组和其它用户没有任何访问权限。
[[email protected] ~]# cp -a /etc/skel/ /home/hadoop [[email protected] ~]# chmod 700 -R /home/hadoop/
5、修改/home/hadoop目录及其内部所有文件的属主为hadoop,属组为hadoop。
[[email protected] ~]# chown -R hadoop:hadoop /home/hadoop/ [[email protected] ~]# ll -d !$ ll -d /home/hadoop/ drwx------. 3 hadoop hadoop 87 6月 28 10:34 /home/hadoop/
6、显示/proc/meminfo文件中以大写或小写S开头的行;用两种方式;
[[email protected] ~]# grep -i ^s /proc/meminfo SwapCached: 0 kB SwapTotal: 4194300 kB SwapFree: 4194300 kB Shmem: 34752 kB Slab: 253416 kB SReclaimable: 176732 kB SUnreclaim: 76684 kB [[email protected] ~]# grep ^[sS] /proc/meminfo SwapCached: 0 kB SwapTotal: 4194300 kB SwapFree: 4194300 kB Shmem: 34752 kB Slab: 253408 kB SReclaimable: 176724 kB SUnreclaim: 76684 kB
7、显示/etc/passwd文件中其默认shell为非/sbin/nologin的用户;
[[email protected] ~]# grep -v /sbin/nologin$ /etc/passwd | cut -d: -f1root sync shutdown halt sh hadoop
8、显示/etc/passwd文件中其默认shell为/bin/bash的用户;
[[email protected] ~]# grep /bin/bash$ /etc/passwd | cut -d: -f1 root sh hadoop
9、找出/etc/passwd文件中的一位数或两位数;
[[email protected]t ~]# grep -o ‘[0-9]\{1,2\}‘ /etc/passwd
10、显示/boot/grub/grub.conf中以至少一个空白字符开头的行;
[[email protected] ~]# grep ‘^[[:space:]]\+‘ /boot/grub/grub.conf root (hd0,0) kernel /vmlinuz-2.6.18-128.el5 ro root=LABEL=/ rhgb quiet initrd /initrd-2.6.18-128.el5.img
11、显示/etc/rc.d/rc.sysinit文件中以#开头,后面跟至少一个空白字符,而后又有至少一个非空白字符的行;
[[email protected] ~]# grep ‘^#[[:space:]]\+[^[:space:]]\+‘ /etc/rc.d/rc.sysinit
12、打出netstat -tan命令执行结果中以‘LISTEN’,后或跟空白字符结尾的行;
[[email protected] ~]# netstat -tan | grep ‘LISTEN[[:space:]]*‘ tcp 0 0 127.0.0.1:2208 0.0.0.0:* LISTEN tcp 0 0 0.0.0.0:845 0.0.0.0:* LISTEN tcp 0 0 0.0.0.0:111 0.0.0.0:* LISTEN tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN tcp 0 0 127.0.0.1:2207 0.0.0.0:* LISTEN tcp 0 0 :::22 :::* LISTEN
13、添加用户bash, testbash, basher, nologin (此一个用户的shell为/sbin/nologin),而后找出当前系统上其用户名和默认shell相同的用户的信息;
[[email protected] ~]# useradd bash [[email protected] ~]# useradd testbash [[email protected] ~]# useradd basher [[email protected] ~]# useradd -s /sbin/nologin nologin [[email protected] ~]# grep ‘^\([[:alnum:]]\+\>\).*\1$‘ /etc/passwd sync:x:5:0:sync:/sbin:/bin/sync shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown halt:x:7:0:halt:/sbin:/sbin/halt bash:x:501:501::/home/bash:/bin/bash nologin:x:504:504::/home/nologin:/sbin/nologin
14、显示/proc/meminfo文件中以大写或小写S开头的行;用三种方式;
[[email protected] ~]# grep -i ^s /proc/meminfo SwapCached: 0 kB SwapTotal: 4096564 kB SwapFree: 4096564 kB Slab: 72724 kB [[email protected] ~]# grep ^[sS] /proc/meminfo SwapCached: 0 kB SwapTotal: 4096564 kB SwapFree: 4096564 kB Slab: 72732 kB [[email protected] ~]# sed -n ‘/^[sS]/p‘ /proc/meminfo SwapCached: 0 kB SwapTotal: 4096564 kB SwapFree: 4096564 kB Slab: 72736 kB
15、显示/etc/passwd文件中其默认shell为非/sbin/nologin的用户;
[[email protected] ~]# grep -v /sbin/nologin$ /etc/passwd | cut -d: -f1root sync shutdown halt news sihua bash testbash basher
16、显示/etc/passwd文件中其默认shell为/bin/bash的用户;
[[email protected] ~]# grep /bin/bash$ /etc/passwd | cut -d: -f1 root sihua bash testbash basher
17、找出/etc/passwd文件中的一位数或两位数;
[[email protected] ~]# grep -o ‘[0-9]\{1,2\}‘ /etc/passwd