1、列出当前系统上所有已经登录的用户的用户名，注意：同一个用户登录多次，则只显示一次即可。
[[email protected] ~]# who root pts/0 2016-08-07 00:40 (192.168.137.2) user2 pts/1 2016-08-07 03:22 (192.168.137.2) user1 pts/2 2016-08-07 03:21 (192.168.137.2) user2 pts/3 2016-08-07 03:23 (192.168.137.2) [[email protected] ~]# who | cut -d" " -f1 root user2 user1 user2 [[email protected] ~]# who | cut -d" " -f1 | sort -u root user1 user2 [[email protected] ~]#
2、取出最后登录到当前系统的用户的相关信息。
[[email protected] ~]# who root pts/0 2016-08-07 00:40 (192.168.137.2) user2 pts/1 2016-08-07 03:22 (192.168.137.2) user1 pts/2 2016-08-07 03:21 (192.168.137.2) user2 pts/3 2016-08-07 03:23 (192.168.137.2) user3 pts/4 2016-08-07 04:56 (192.168.137.2) [[email protected] ~]# who | sort -r | head -n 1 | cut -d" " -f1 | id uid=0(root) gid=0(root) groups=0(root) context=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 [[email protected] ~]#
3、取出当前系统上被用户当作其默认shell的最多的那个shell。
cut -d: -f7 /etc/passwd | uniq -c | sort -n | tail -n 1 | grep -E -o "/.*"
4、将/etc/passwd 中的第三个字段数值最大的后10个用户的信息全部改为大写后保存至/tmp/maxusers.txt文件中。
[[email protected] tmp]# sort -n -k 3 -t":" /etc/passwd | tail -n 10 | tr [a-z] [A-Z] > /tmp/maxusers.txt [[email protected] tmp]# cat /tmp/maxusers.txt ABRT:X:173:173::/ETC/ABRT:/SBIN/NOLOGIN PULSE:X:497:496:PULSEAUDIO SYSTEM DAEMON:/VAR/RUN/PULSE:/SBIN/NOLOGIN SASLAUTH:X:498:76:SASLAUTHD USER:/VAR/EMPTY/SASLAUTH:/SBIN/NOLOGIN RTKIT:X:499:499:REALTIMEKIT:/PROC:/SBIN/NOLOGIN MU:X:500:500:MU:/HOME/MU:/BIN/BASH USER1:X:501:501::/HOME/USER1:/BIN/BASH USER2:X:502:502::/HOME/USER2:/BIN/BASH USER3:X:503:503::/HOME/USER3:/BIN/BASH DFF_GRT:X:504:504::/HOME/DFF_GRT:/BIN/BASH NFSNOBODY:X:65534:65534:ANONYMOUS NFS USER:/VAR/LIB/NFS:/SBIN/NOLOGIN [[email protected] tmp]#
5、取出当前主机的IP地址，提示：对ifconfig命令的结果进行切分。
[[email protected] tmp]# ifconfig eth0 Link encap:Ethernet HWaddr 00:0C:29:C6:4F:C7 inet addr:192.168.137.3 Bcast:192.168.137.255 Mask:255.255.255.0 inet6 addr: fe80::20c:29ff:fec6:4fc7/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:79309 errors:0 dropped:0 overruns:0 frame:0 TX packets:25674 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:10809561 (10.3 MiB) TX bytes:3665156 (3.4 MiB) lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:65536 Metric:1 RX packets:7436 errors:0 dropped:0 overruns:0 frame:0 TX packets:7436 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:602496 (588.3 KiB) TX bytes:602496 (588.3 KiB) [[email protected] tmp]# ifconfig | grep -E "\<inet\>" | cut -d":" -f2 | cut -d" " -f1 192.168.137.3 127.0.0.1 [[email protected] tmp]#
6、列出/etc目录下所有以.conf结尾的文件的文件名，并将其名字转换为大写后保存至/tmp/etc.conf文件中。
[[email protected] ~]$ ls /etc/ | grep -E ".conf$" | tr [a-z] [A-Z] > /tmp/etc.conf [[email protected] ~]$ cat /tmp/etc.conf ANTHY-CONF ASOUND.CONF AUTOFS.CONF AUTOFS_LDAP_AUTH.CONF CAS.CONF DNSMASQ.CONF DRACUT.CONF FPRINTD.CONF GAI.CONF GCONF GRUB.CONF GSSAPI_MECH.CONF HOST.CONF IDMAPD.CONF INIT.CONF KDUMP-ADV-CONF KDUMP.CONF KRB5.CONF LATRACE.CONF LD.SO.CONF LIBAUDIT.CONF LIBUSER.CONF LOGROTATE.CONF LTRACE.CONF MKE2FS.CONF MTOOLS.CONF NFSMOUNT.CONF NSSWITCH.CONF NTP.CONF ODDJOBD.CONF PBM2PPA.CONF PM-UTILS-HD-APM-RESTORE.CONF PNM2PPA.CONF PRELINK.CONF READAHEAD.CONF REQUEST-KEY.CONF RESOLV.CONF RSYSLOG.CONF SESTATUS.CONF SMARTD.CONF SOS.CONF SUDO.CONF SUDO-LDAP.CONF SYSCTL.CONF TROLLTECH.CONF UPDATEDB.CONF WARNQUOTA.CONF YP.CONF YUM.CONF [[email protected] ~]$
7、显示/var目录下一级子目录或文件的总个数。
[[email protected] var]$#/var一级子目录或文件总个数： [[email protected] var]$ ls -l | grep "^[d|-]" drwxr-xr-x. 2 root root 4096 Jul 31 19:12 account drwxr-xr-x. 15 root root 4096 Jul 31 19:23 cache drwxr-xr-x. 2 root root 4096 May 11 07:55 crash drwxr-xr-x. 2 root root 4096 Nov 22 2013 cvs drwxr-xr-x. 3 root root 4096 Jul 31 19:12 db drwxr-xr-x. 3 root root 4096 Jul 31 19:11 empty drwxr-xr-x. 2 root root 4096 Sep 23 2011 games drwxrwx--T. 2 root gdm 4096 Oct 16 2014 gdm drwxr-xr-x. 38 root root 4096 Aug 7 03:35 lib drwxr-xr-x. 2 root root 4096 Sep 23 2011 local drwxrwxr-x. 5 root lock 4096 Aug 7 03:35 lock drwxr-xr-x. 13 root root 4096 Aug 7 03:35 log drwxr-xr-x. 2 root root 4096 Sep 23 2011 nis drwxr-xr-x. 2 root root 4096 Sep 23 2011 opt drwxr-xr-x. 2 root root 4096 Sep 23 2011 preserve drwxr-xr-x. 28 root root 4096 Aug 5 04:25 run drwxr-xr-x. 13 root root 4096 Jul 31 19:07 spool drwxrwxrwt. 2 root root 4096 Jul 31 19:16 tmp drwxr-xr-x. 6 root root 4096 Jul 31 19:06 www drwxr-xr-x. 3 root root 4096 Jul 31 19:06 yp [[email protected] var]$ ls -l | grep "^[d|-]" | wc -l 20 [[email protected] var]$
8、取出/etc/group文件中第三个字段数值最小的10个组的名字。
[[email protected] ~]$ sort -n -t ":" -k 3 /etc/group | head -n 10 | cut -d: -f1 root bin daemon sys adm tty disk lp mem kmem [[email protected] ~]$
9、将/etc/fstab和/etc/issue文件的内容合并为同一个内容后保存至/tmp/etc.test文件中。
[[email protected] ~]$ cat /etc/fstab /etc/issue >> /tmp/etc.test [[email protected] ~]$ cat /tmp/etc.test | wc -l 18 [[email protected] ~]$ cat /tmp/etc.test # # /etc/fstab # Created by anaconda on Sun Jul 31 18:58:06 2016 # # Accessible filesystems, by reference, are maintained under ‘/dev/disk‘ # See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info # /dev/mapper/vg_client-lv_root / ext4 defaults 1 1 UUID=769bb69c-b8ce-4ce5-80e0-7f0a273536d6 /boot ext4 defaults 1 2 /dev/mapper/vg_client-lv_swap swap swap defaults 0 0 tmpfs /dev/shm tmpfs defaults 0 0 devpts /dev/pts devpts gid=5,mode=620 0 0 sysfs /sys sysfs defaults 0 0 proc /proc proc defaults 0 0 CentOS release 6.8 (Final) Kernel \r on an \m [[email protected] ~]$
10、请总结描述用户和组管理类命令的使用方法并完成以下练习：
(1)、创建组distro，其GID为2016；
[[email protected] ~]# groupadd distro -g 2016
(2)、创建用户mandriva, 其ID号为1005；基本组为distro；
[[email protected] ~]# useradd mandriva -u 1005 -g distro
(3)、创建用户mageia，其ID号为1100，家目录为/home/linux;
[[email protected] ~]# mkdir -p /home/linux [[email protected] ~]# useradd mageia -u 1100 -d /home/linux/
(4)、给用户mageia添加密码，密码为mageedu；
[[email protected] ~]# echo "mageedu" | passwd --stdin mageia
(5)、删除mandriva，但保留其家目录；
[[email protected] ~]# userdel mandriva
(6)、创建用户slackware，其ID号为2002，基本组为distro，附加组peguin；
[[email protected] ~]# useradd slackware -u 2002 -g distro [[email protected] ~]# groupadd peguin [[email protected] ~]# usermod slackware -aG peguin [[email protected] ~]# id slackware uid=2002(slackware) gid=2016(distro) groups=2016(distro),2017(peguin)
(7)、修改slackware的默认shell为/bin/tcsh；
[[email protected] ~]# usermod -s /bin/tcsh slackware [[email protected] ~]# cat /etc/passwd | tail -n 1 slackware:x:2002:2016::/home/slackware:/bin/tcsh
(8)、为用户slackware新增附加组admins；
[[email protected] ~]# groupadd admins [[email protected] ~]# usermod slackware -aG admins [[email protected] ~]# id slackware uid=2002(slackware) gid=2016(distro) groups=2016(distro),2017(peguin),2018(admins)
(9)、为slackware添加密码，且要求密码最短使用期限为3天，最长为180天，警告为3天；
[[email protected] ~]# echo "mageedu" | passwd --stdin slackware Changing password for user slackware. passwd: all authentication tokens updated successfully. [[email protected] ~]# chage -m 3 -M 180 -W 3 slackware [[email protected] ~]# cat /etc/shadow | tail -n 1 slackware:$6$bdbYcoWR$3UAiElPQWmATJsw.I7x6Lx9OdJwIlIadeKOY.BLRinErFRAxaJZqB.fhHaacPs7Oi.n6S/tBclVk9yq9L51cp.:17020:3:180:3:::
(10)、添加用户openstack，其ID号为3003, 基本组为clouds，附加组为peguin和nova；
[[email protected] ~]# groupadd clouds [[email protected] ~]# groupadd nova [[email protected] ~]# useradd openstack -u 3003 -g clouds [[email protected] ~]# usermod -aG peguin,nova openstack [[email protected] ~]# id openstack uid=3003(openstack) gid=2019(clouds) groups=2019(clouds),2017(peguin),2020(nova)
(11)、添加系统用户mysql，要求其shell为/sbin/nologin；
[[email protected] ~]# useradd mysql [[email protected] ~]# usermod -s /sbin/nologin mysql [[email protected] ~]# cat /etc/passwd | tail -n 1 mysql:x:3004:3004::/home/mysql:/sbin/nologin
(12)、使用echo命令，非交互式为openstack添加密码。
[[email protected] ~]# echo "newpasswd" | passwd --stdin openstack Changing password for user openstack. passwd: all authentication tokens updated successfully.
时间： 2024-10-29 22:48:39