1、復制/etc/skel目錄為/home/tuser1,要求/home/tuser1及其內部文件的屬組和其它用戶均沒有任何訪問權限。
[root@llww3317 ~]# cp -r /etc/skel /home [root@llww3317 ~]# mv /home/skel /home/tuser1 [root@llww3317 ~]# chmod g-r,o-r /home/tuser1 [root@llww3317 ~]# ll -a /home/ |grep tuser1 drwx--x--x. 2 root root 59 7月 4 15:12 tuser1 [root@llww3317 ~]# chmod g-r,o-r /home/tuser1/.* [root@llww3317 ~]# ll -a /home/tuser1 總用量 16 drwx--x--x. 2 root root 59 7月 4 15:12 . d-wx--x--x. 10 root root 4096 7月 4 15:13 .. -rw-------. 1 root root 18 7月 4 15:12 .bash_logout -rw-------. 1 root root 193 7月 4 15:12 .bash_profile -rw-------. 1 root root 231 7月 4 15:12 .bashrc
2、編輯/etc/group文件,添加組hadoop
[root@llww3317 ~]# vi /etc/group hadoop:x:3500: #最后一行輸入
3、手動/etc/passwd文件新增一行,添加用戶hadoop,其基本組ID為hadoop組的id號; 其家目錄為/home/hadoop 。
[root@llww3317 ~]# vi /etc/passwd hadoop:x:3500:3500::/home/hadoop:/bin/bash
4、復制/etc/skel目錄為/home/hadoop,要求修改hadoop目錄的屬組和其它用戶沒有任何訪問權限。
root@llww3317 ~]# cp -r /etc/skel /home [root@llww3317 ~]# mv /home/skel /home/hadoop [root@llww3317 ~]# chmod g-r,o-r /home/hadoop [root@llww3317 ~]# ll /home |grep hadoop drwx--x--x. 2 root root 59 7月 4 15:19 hadoop
5、修改/home/hadoop目錄及其內部所有文件的屬主為hadoop,屬組為hadoop
[root@llww3317 ~]# chown hadoop:hadoop /home/hadoop [root@llww3317 ~]# chown hadoop:hadoop /home/hadoop/.* [root@llww3317 ~]# ll -a /home/hadoop 總用量 16 drwx--x--x. 2 hadoop hadoop 59 7月 4 15:19 . d-wx--x--x. 10 hadoop hadoop 4096 7月 4 15:19 .. -rw-r--r--. 1 hadoop hadoop 18 7月 4 15:19 .bash_logout -rw-r--r--. 1 hadoop hadoop 193 7月 4 15:19 .bash_profile -rw-r--r--. 1 hadoop hadoop 231 7月 4 15:19 .bashrc [root@llww3317 ~]# ll /home |grep hadoop drwx--x--x. 2 hadoop hadoop 59 7月 4 15:19 hadoop
6、顯示/proc/meminfo文件中以大寫或小寫S開頭的行;用三種方式
[root@llww3317 ~]# cat /proc/meminfo |grep "^[s,S]" SwapCached: 0 kB SwapTotal: 2228220 kB SwapFree: 2228220 kB Shmem: 8756 kB Slab: 57520 kB SReclaimable: 23232 kB SUnreclaim: 34288 kB [root@llww3317 ~]# sed -n '/^[s,S]/p' /proc/meminfo SwapCached: 0 kB SwapTotal: 2228220 kB SwapFree: 2228220 kB Shmem: 8756 kB Slab: 57520 kB SReclaimable: 23232 kB SUnreclaim: 34288 kB [root@llww3317 ~]# awk '/^[s,S]/' /proc/meminfo SwapCached: 0 kB SwapTotal: 2228220 kB SwapFree: 2228220 kB Shmem: 8756 kB Slab: 57520 kB SReclaimable: 23232 kB SUnreclaim: 34288 kB
7、顯示/etc/passwd文件中其默認shell為非/sbin/nologin的用戶
[root@llww3317 ~]# cat /etc/passwd |grep -v /sbin/nologin root:x:0:0:root:/root:/bin/bash sync:x:5:0:sync:/sbin:/bin/sync shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown halt:x:7:0:halt:/sbin:/sbin/halt mageia:x:1100:1100::/home/linux:/bin/bash slackware:x:2002:2016::/home/slackware:/bin/tcsh openstack:x:3003:2020::/home/openstack:/bin/bash user:x:3004:3004::/home/user:/bin/bash hadoop:x:3500:3500::/home/hadoop:/bin/bash [root@llww3317 ~]# sed -n '/[*\/[^sbin]\/[^nologin]/p' /etc/passwd root:x:0:0:root:/root:/bin/bash sync:x:5:0:sync:/sbin:/bin/sync shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown halt:x:7:0:halt:/sbin:/sbin/halt avahi-autoipd:x:170:170:Avahi IPv4LL Stack:/var/lib/avahi-autoipd:/sbin/nologin mageia:x:1100:1100::/home/linux:/bin/bash slackware:x:2002:2016::/home/slackware:/bin/tcsh openstack:x:3003:2020::/home/openstack:/bin/bash user:x:3004:3004::/home/user:/bin/bash hadoop:x:3500:3500::/home/hadoop:/bin/bash
8、顯示/etc/passwd文件中其默認shell為/bin/bash的用戶
[root@llww3317 ~]# sed -n '/\/bin\/bash$/p' /etc/passwd root:x:0:0:root:/root:/bin/bash mageia:x:1100:1100::/home/linux:/bin/bash openstack:x:3003:2020::/home/openstack:/bin/bash user:x:3004:3004::/home/user:/bin/bash hadoop:x:3500:3500::/home/hadoop:/bin/bash
9、找出/etc/passwd文件中的一位數或兩位數
[root@llww3317 ~]# awk '/\<[[:digit:]]{1,2}\>/' /etc/passwd root:x:0:0:root:/root:/bin/bash bin:x:1:1:bin:/bin:/sbin/nologin daemon:x:2:2:daemon:/sbin:/sbin/nologin adm:x:3:4:adm:/var/adm:/sbin/nologin lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin sync:x:5:0:sync:/sbin:/bin/sync shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown halt:x:7:0:halt:/sbin:/sbin/halt mail:x:8:12:mail:/var/spool/mail:/sbin/nologin operator:x:11:0:operator:/root:/sbin/nologin games:x:12:100:games:/usr/games:/sbin/nologin ftp:x:14:50:FTP User:/var/ftp:/sbin/nologin nobody:x:99:99:Nobody:/:/sbin/nologin dbus:x:81:81:System message bus:/:/sbin/nologin tss:x:59:59:Account used by the trousers package to sandbox the tcsd daemon:/dev/null:/sbin/nologin postfix:x:89:89::/var/spool/postfix:/sbin/nologin sshd:x:74:74:Privilege-separated SSH:/var/empty/sshd:/sbin/nologin
10、顯示/boot/grub/grub.conf中以至少一個空白字符開頭的行
CentOS 7下沒有該文件,在/tmp下新建了10.sh
[root@llww3317 ~]# more /tmp/10.sh aaaaaaaaa bbbbbbb ccccccccccc dddddddddd eeeeeeeeeee ffffffffffffff ggggggggggg hhhhhhhhh iiiiiii [root@llww3317 ~]# cat /tmp/10.sh |grep '^[[:space:]]\{1,\}' aaaaaaaaa bbbbbbb eeeeeeeeeee ffffffffffffff ggggggggggg iiiiiii
11、顯示/etc/rc.d/rc.sysinit文件 中以#開頭,后面跟至少一個空白字符,而后又有至少一個非空白字符的行
[root@llww3317 ~]# more /tmp/11.sh # # # aaaaaaa aaaaaa aaaaaa #bbbbbb bbbbb bbbbbbbbb # cccccccccccccccc #ddddd ddddd dddddddd # eeeeee eeeee e e e e sdfsdf sd fsd f sdf sdf sd f sdf sd fsd [root@llww3317 ~]# grep '^#[[:space:]]\{1,\}[^[:space:]]' /tmp/11.sh # aaaaaaa aaaaaa aaaaaa # cccccccccccccccc # eeeeee eeeee e e e e
12、打出netstat -tan命令執行結果中以‘LISTEN’ ,后面跟空白字符結尾的行
netstat -tan | grep 'LISTEN[[:space:]]'
13、添加用戶bash, testbash, basher, nologin(此一個用戶的shell為/sbin/nologin),而后找出當前系統上其用戶名和默認shell相同的用戶的信息
useradd bash useradd testbash useradd basher useradd -s /sbin/nologin nologin # egrep "^([[:alnum:]]+\>).*\1$" /etc/passwd
原創文章,作者:laiwen2007,如若轉載,請注明出處:http://www.www58058.com/17576