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@host1 ~]# cp -a /etc/skel /home/tuser1 [root@host1 ~]# chmod -R go-rwx /home/tuser1
2、编辑/etc/group文件，添加组hadoop。
[root@host1 ~]# echo "hadoop:x:2048:" >> /etc/group
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@host1 ~]# echo 'hadoop:x:2048:2048::/home/hadoop:/sbin/nologin' >> /etc/passwd
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@host1 ~]# cp -a /etc/skel /home/hadoop [root@host1 ~]# chmod -R og-rwx /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。
[root@host1 ~]# chown -R hadoop.hadoop /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@host1 ~]# grep '^[sS]' /proc/meminfo SwapCached: 108 kB SwapTotal: 2097148 kB SwapFree: 2096984 kB Shmem: 25500 kB Slab: 102272 kB SReclaimable: 54692 kB SUnreclaim: 47580 kB [root@host1 ~]# grep -i '^s' /proc/meminfo SwapCached: 108 kB SwapTotal: 2097148 kB SwapFree: 2096984 kB Shmem: 25500 kB Slab: 102528 kB SReclaimable: 55004 kB SUnreclaim: 47524 kB
7、显示/etc/passwd文件中其默认shell为非/sbin/nologin的用户；
[root@host1 ~]# grep -v ':/sbin/nologin$' /etc/passwd | awk -F: '{print $1}'
root
sync
shutdown
halt
mageia
slackware
openstack
8、显示/etc/passwd文件中其默认shell为/bin/bash的用户；
[root@host1 ~]# grep -oP '^\w+?(?=:.*/bin/bash$)' /etc/passwd root mageia openstack
9、找出/etc/passwd文件中的一位数或两位数；
[root@host1 ~]# grep -oP '\b\d{1,2}\b' /etc/passwd
0
0
1
1
2
2
3
4
4
7
5
0
6
0
7
0
8
12
11
0
12
14
50
99
99
81
81
59
59
89
89
74
74
38
38
25
25
10、显示/boot/grub/grub.conf中以至少一个空白字符开头的行；
[root@cloud ~]# grep -P '^\s+' /boot/grub/grub.conf root (hd0,0) kernel /vmlinuz-2.6.32-358.el6.i686 ro root=/dev/mapper/vg_cloud-lv_root rd_NO_LUKS rd_NO_MD rd_LVM_LV=vg_cloud/lv_swap crashkernel=auto.UTF-8 rd_LVM_LV=vg_cloud/lv_root KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM rhgb quiet initrd /initramfs-2.6.32-358.el6.i686.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@cloud ~]# grep -P '^#\s+\S+' /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). # Update quotas if necessary # Check to see if a full relabel is needed # 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’，后或跟空白字符结尾的行；
[root@cloud ~]# netstat -tan | grep -P 'LISTEN\s*$' tcp 0 0 0.0.0.0:5902 0.0.0.0:* LISTEN tcp 0 0 0.0.0.0:111 0.0.0.0:* LISTEN tcp 0 0 0.0.0.0:8880 0.0.0.0:* LISTEN tcp 0 0 0.0.0.0:6002 0.0.0.0:* LISTEN tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN tcp 0 0 0.0.0.0:12346 0.0.0.0:* LISTEN tcp 0 0 127.0.0.1:25151 0.0.0.0:* LISTEN tcp 0 0 0.0.0.0:63009 0.0.0.0:* LISTEN tcp 0 0 0.0.0.0:8388 0.0.0.0:* LISTEN tcp 0 0 :::111 :::* LISTEN tcp 0 0 :::80 :::* LISTEN tcp 0 0 :::14513 :::* LISTEN tcp 0 0 :::6002 :::* LISTEN tcp 0 0 :::22 :::* LISTEN tcp 0 0 ::1:631 :::* LISTEN tcp 0 0 ::1:25 :::* LISTEN tcp 0 0 :::443 :::* LISTEN
13、添加用户bash, testbash, basher, nologin (此一个用户的shell为/sbin/nologin)，而后找出当前系统上其用户名和默认shell相同的用户的信息；
[root@host1 ~]# grep -P '^(\w+):.*\1$' /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 nologin:x:2052:2052::/home/nologin:/sbin/nologin
原创文章，作者：gateray，如若转载，请注明出处：http://www.178linux.com/21085
评论列表（1条）
写的很好，有的题目是不是没做完，加油