1、显示/boot/grub/grub.conf中以至少一个空白字符开头的行;
[root@localhost ~]# grep "^[[:space:]]\+" /boot/grub/grub.conf root (hd0,0) kernel /vmlinuz-2.6.32-642.el6.x86_64 ro root=/dev/mapper/VolGroup-lv_root rd_NO_LUKS LANG=en_US.UTF-8 rd_NO_MD rd_LVM_LV=VolGroup/lv_swap SYSFONT=latarcyrheb-sun16 crashkernel=auto rd_LVM_LV=VolGroup/lv_root KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM rhgb quiet initrd /initramfs-2.6.32-642.el6.x86_64.img
2、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@localhost ~]# grep '^#[[: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. ....
3、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@localhost ~]# netstat -tan | grep '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 0.0.0.0:46074 0.0.0.0:* LISTEN tcp 0 0 :::111 :::* LISTEN tcp 0 0 :::41268 :::* LISTEN tcp 0 0 :::22 :::* LISTEN tcp 0 0 ::1:631 :::* LISTEN tcp 0 0 ::1:25 :::* LISTEN
4、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@localhost ~]#useradd bash [root@localhost ~]#useradd testbash [root@localhost ~]#useradd basher [root@localhost ~]#useradd -s /sbin/nologin nologin [root@localhost ~]# grep --color=auto "^\([[:alnum:]]\+\>\).*\1$" /etc/passwd sync:x:5:0:sync:/sbin:/bin/sync shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown halt:x:7:0:halt:/sbin:/sbin/halt bash:x:3006:3006::/home/bash:/bin/bash nologin:x:3009:3009::/home/nologin:/sbin/nologin
5、显示当前系统上root、fedora或user1用户的默认shell;
#!/bin/bash for i in {root,fedora,user1};do reslut=`grep "^\" /etc/passwd | cut -d: -f7` echo "$i shell is $reslut" done
6、找出/etc/rc.d/init.d/functions文件中某单词后面跟一组小括号的行,形如:hello();
[root@localhost ~]# grep "\([[:alpha:]]\+\)()" /etc/rc.d/init.d/functions fstab_decode_str() { checkpid() { __readlink() { __fgrep() { __kill_pids_term_kill_checkpids() { __kill_pids_term_kill() { __umount_loop() { __source_netdevs_fstab() { __source_netdevs_mtab() { ...
7、使用echo命令输出一个绝对路径,使用grep取出其基名;
[root@localhost ~]# echo "/etc/sysconfig/" | sed 's@^.*/\([^/]\+\)/\?$@\1@' sysconfig
扩展:取出其路径名
[root@localhost ~]# echo "/etc/sysconfig/" | sed 's@[^/]\+/\?$@@' /etc/
8、找出ifconfig命令结果中的1-255之间数字;
[root@localhost ~]# ifconfig | grep --colour=auto -E -o "\|\|\|\"
9、挑战题:写一个模式,能匹配合理的IP地址;
ifconfig | grep --color=auto -E -o "(\.){3}\"|head -1
10、挑战题:写一个模式,能匹配出所有的邮件地址;
grep ".*@.*" mail
11、查找/var目录下属主为root,且属组为mail的所有文件或目录;
[root@localhost ~]# find /var/ -user root -a -group mail -ls 394263 4 drwxrwxr-x 2 root mail 4096 Jul 21 12:58 /var/spool/mail
12、查找当前系统上没有属主或属组的文件;
[root@localhost ~]# find / -nouser -o -nogroup
进一步:查找当前系统上没有属主或属组,且最近3天内曾被访问过的文件或目录;
[root@localhost ~]#useradd test [root@localhost ~]#userdel test [root@localhost ~]# find / -nouser -a -nogroup -a -atime -3 -ls 3145729 4 drwx------ 4 500 500 4096 Jul 5 14:55 /home/test 3145733 4 drwxr-xr-x 4 500 500 4096 Jul 5 14:17 /home/test/.mozilla 3145735 4 drwxr-xr-x 2 500 500 4096 Aug 18 2010 /home/test/.mozilla/extensions 3145734 4 drwxr-xr-x 2 500 500 4096 Aug 18 2010 /home/test/.mozilla/plugins 3145736 4 drwxr-xr-x 2 500 500 4096 Nov 12 2010 /home/test/.gnome2
13、查找/etc目录下所有用户都有写权限的文件;
[root@localhost ~]# find /etc/ -perm -222 -ls
14、查找/etc目录下大于1M,且类型为普通文件的所有文件;
[[root@localhost ~]# find /etc/ -size +1M -a -type f -ls
15、查找/etc/init.d/目录下,所有用户都有执行权限,且其它用户有写权限的文件;
[root@localhost ~]# chmod o+w /etc/init.d/sssd [root@localhost ~]# find /etc/init.d/ -perm -113 -ls 918508 4 -rwxr-xrwx 1 root root 2690 May 11 16:04 /etc/init.d/sssd
16、查找/usr目录下不属于root、bin或hadoop的文件;
[root@localhost ~]# find /usr/ -not \( -user root -o -user bin -o -user hadoop \) -ls 1974438 12 -rwsr-xr-x 1 abrt abrt 10296 May 12 04:43 /usr/libexec/abrt-action-install-debuginfo-to-abrt-cache
17、查找/etc/目录下至少有一类用户没有写权限的文件;
[root@localhost ~]# find /etc/ -not -perm /222 -ls
18、查找/etc目录下最近一周内其内容被修改过,且不属于root或hadoop的文件;
[root@localhost ~]#find /etc/ -user root -a -user hadoop -a -mtime -7 -ls
原创文章,作者:Net21_Lion,如若转载,请注明出处:http://www.178linux.com/23821
评论列表(1条)
写的很好,排版也很棒,加油