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；
[root@Client skel]# cp -R /etc/skel/ /home/tuser1[root@Client skel]# chmod -R 700 /home/tuser1/[root@Client skel]# ls -dl /home/tuser1/drwx------. 4 root root 4096 Aug 9 08:19 /home/tuser1/[root@Client skel]# ls -al /home/tuser1/total 28drwx------. 4 root root 4096 Aug 9 08:19 .drwxr-xr-x. 14 root root 4096 Aug 9 08:19 ..-rwx------. 1 root root 18 Aug 9 08:19 .bash_logout-rwx------. 1 root root 176 Aug 9 08:19 .bash_profile-rwx------. 1 root root 124 Aug 9 08:19 .bashrcdrwx------. 2 root root 4096 Aug 9 08:19 .gnome2drwx------. 4 root root 4096 Aug 9 08:19 .mozilla
2、编辑/etc/group文件，添加组hadoop；
[root@Client home]# vim /etc/group[root@Client home]# tail -n 1 /etc/grouphadoop:x:505:
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；
[root@Client ~]# tail -n 1 /etc/passwdhadoop:x:505:505::/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；
[root@Client hadoop]# cp -R /etc/skel/ /home/hadoop[root@Client hadoop]# chmod -R 700 /home/hadoop/[root@Client hadoop]# ll -dl /home/hadoop/drwx------. 4 root root 4096 Aug 9 12:01 /home/hadoop/[root@Client hadoop]# ll -al /home/hadooptotal 28drwx------. 4 root root 4096 Aug 9 12:01 .drwxr-xr-x. 15 root root 4096 Aug 9 12:01 ..-rwx------. 1 root root 18 Aug 9 12:01 .bash_logout-rwx------. 1 root root 176 Aug 9 12:01 .bash_profile-rwx------. 1 root root 124 Aug 9 12:01 .bashrcdrwx------. 2 root root 4096 Aug 9 12:01 .gnome2drwx------. 4 root root 4096 Aug 9 12:01 .mozilla
5、修改/home/hadoop目录及其内部所有文件的属主为hadoop，属组为hadoop；
[root@Client home]# chown -R hadoop:hadoop /home/hadoop/[root@Client home]# ll -al /home/hadoop/total 28drwx------. 4 hadoop hadoop 4096 Aug 9 12:01 .drwxr-xr-x. 15 root root 4096 Aug 9 12:01 ..-rwx------. 1 hadoop hadoop 18 Aug 9 12:01 .bash_logout-rwx------. 1 hadoop hadoop 176 Aug 9 12:01 .bash_profile-rwx------. 1 hadoop hadoop 124 Aug 9 12:01 .bashrcdrwx------. 2 hadoop hadoop 4096 Aug 9 12:01 .gnome2drwx------. 4 hadoop hadoop 4096 Aug 9 12:01 .mozilla[root@Client home]# ll -dl /home/hadoop/drwx------. 4 hadoop hadoop 4096 Aug 9 12:01 /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；
[root@Client home]# grep -E "^[sS]" /proc/meminfo #方法1SwapCached: 0 kBSwapTotal: 2031612 kBSwapFree: 2031612 kBShmem: 1140 kBSlab: 102148 kBSReclaimable: 39044 kBSUnreclaim: 63104 kB[root@Client home]# grep -Ev "^[^sS]" /proc/meminfo #方法2SwapCached: 0 kBSwapTotal: 2031612 kBSwapFree: 2031612 kBShmem: 1140 kBSlab: 102152 kBSReclaimable: 39048 kBSUnreclaim: 63104 kB
7、显示/etc/passwd文件中其默认shell为非/sbin/nologin的用户；
[root@Client home]# cut -d: -f1,7 /etc/passwd | grep -Ev "/sbin/nologin$" | cut -d: -f1rootsyncshutdownhaltmuuser1user2user3dff_grtmageiamageiaaslackwareopenstackhadoop
8、显示/etc/passwd文件中其默认shell为/bin/bash的用户；
[root@Client home]# cut -d: -f1,7 /etc/passwd | grep -E "/bin/bash$" | cut -d: -f1rootmuuser1user2user3dff_grtmageiamageiaaopenstackhadoop
9、找出/etc/passwd文件中的一位数或两位数；
[root@Client home]# cat /etc/passwd | grep -Eo "\<[0-9][0-9]?\>"00112234475060708121014110121330145099998181323269692929686838384848768989424274747272
10、显示/boot/grub/grub.conf中以至少一个空白字符开头的行；
[root@Client home]# grep -E "^[[:space:]]+" /boot/grub/grub.conf root (hd0,0) kernel /vmlinuz-2.6.32-642.el6.x86_64 ro root=/dev/mapper/vg_client-lv_root rd_NO_LUKS LANG=en_US.UTF-8 rd_LVM_LV=vg_client/lv_root rd_NO_MD rd_LVM_LV=vg_client/lv_swap SYSFONT=latarcyrheb-sun16 crashkernel=auto KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM rhgb quiet initrd /initramfs-2.6.32-642.el6.x86_64.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；
[root@Client home]# grep -E "^#[[:space:]]+[^[:space:]]+" /etc/rc.d/rc.sysinit # /etc/rc.d/rc.sysinit - run once at boot time# Taken in part from Miquel van Smoorenburg's bcheckrc.# Check SELinux status# Print a text banner.# Only read this once.# Initialize hardware# Set default affinity# Load other user-defined modules# Load modules (for backward compatibility with VARs)# Configure kernel parameters# Set the hostname.# Sync waiting for storage.# Device mapper & related initialization# Start any MD RAID arrays that haven't been started yet# Remount the root filesystem read-write.# Clean up SELinux labels# If relabeling, relabel mount points.# Mount all other filesystems (except for NFS and /proc, which is already# mounted). Contrary to standard usage,# filesystems are NOT unmounted in single user mode.# The 'no' applies to all listed filesystem types. See mount(8).# Check to see if a full relabel is needed# Update quotas if necessary# Initialize pseudo-random number generator# Configure machine if necessary.# Clean out /.# Do we need (w|u)tmpx files? We don't set them up, but the sysadmin might...# Clean up /var.# Clean up utmp/wtmp# Clean up various /tmp bits# Make ICE directory# Start up swapping.# Set up binfmt_misc# Boot time profiles. Yes, this should be somewhere else.# Now that we have all of our basic modules loaded and the kernel going,# let's dump the syslog ring somewhere so we can find it later# create the crash indicator flag to warn on crashes, offer fsck with timeout# Let rhgb know that we're leaving rc.sysinit
12、打出netstat -tan命令执行结果中以‘LISTEN’，后跟空白字符结尾的行；
[root@Client home]# netstat -tan | grep -E "LISTEN[[:space:]]" tcp 0 0 0.0.0.0:111 0.0.0.0:* LISTEN tcp 0 0 0.0.0.0:22 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 0.0.0.0:35098 0.0.0.0:* LISTEN tcp 0 0 :::43279 :::* LISTEN tcp 0 0 :::111 :::* LISTEN tcp 0 0 :::22 :::* LISTEN tcp 0 0 ::1:631 :::* LISTEN tcp 0 0 ::1:25 :::* 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；
[root@Client home]# grep -E "^(\<[[:alpha:]]+\>).*\1$" /etc/passwdsync:x:5:0:sync:/sbin:/bin/syncshutdown:x:6:0:shutdown:/sbin:/sbin/shutdownhalt:x:7:0:halt:/sbin:/sbin/haltbash:x:3005:3005::/home/bash:/bin/bashnologin:x:3008:3008::/home/nologin:/sbin/nologin