1.列出当前系统上所有已经登录的用户的用户名，注：同一个用户登录多次，则只显示一次即可。
who | cut -d ‘ ‘ -f1 | sort -u
[root@localhost ~]# who
danry :0 -07-16 23:20 (:0)
danry pts/0 -07-16 23:23 (192.168.1.2)
root pts/1 -07-16 23:30 (192.168.1.2)
[root@localhost ~]#
[root@localhost ~]#
[root@localhost ~]# who | cut -d ' ' -f1 | sort -u
danry
root
[root@localhost ~]#
2.列出最后登录到当前系统的用户的相关信息。
(1),last | head -1
[root@localhost ~]# last | head -1
root pts/3 192.168.1.2 Mon Jul 17 01:05 still logged in
[root@localhost ~]# who
danry :0 -07-16 23:20 (:0)
danry pts/0 -07-16 23:23 (192.168.1.2)
root pts/1 -07-16 23:30 (192.168.1.2)
danry pts/2 -07-16 23:46 (192.168.1.2)
root pts/3 -07-17 01:05 (192.168.1.2)
[root@localhost ~]#
(2),id last | head -1 | cut -d ‘ ‘ -f1`
[root@localhost ~]# id `last | head -1 | cut -d ' ' -f1`
uid=1000(danry) gid=1000(danry) groups=1000(danry),10(wheel)
[root@localhost ~]# ^C
[root@localhost ~]# who
danry :0 -07-16 23:20 (:0)
danry pts/0 -07-16 23:23 (192.168.1.2)
root pts/1 -07-16 23:30 (192.168.1.2)
danry pts/2 -07-16 23:46 (192.168.1.2)
[root@localhost ~]#
3.列出当前系统上被用户当作其默认shell的最多的那个shell。
(1),echo $0
[root@localhost ~]# echo $0
-bash
[root@localhost ~]#
(2),echo $SHELL
[root@localhost ~]# echo $SHELL
/bin/bash
[root@localhost ~]#
4.讲/etc/passwd中的第三个字段数值最大的10个用户的信息全部改为大写后保存至/tmp/maxusers.txt文件中。
sort -t: -k3 -n -r /etc/passwd | head -10 | tr ‘a-z’ ‘A-Z’
[root@localhost ~]# sort -t: -k3 -n -r /etc/passwd | head -10 | tr 'a-z' 'A-Z' > /tmp/maxusers.txt
[root@localhost ~]#
[root@localhost ~]# cat /tmp/maxusers.txt
NFSNOBODY:X:65534:65534:ANONYMOUS NFS USER:/VAR/LIB/NFS:/SBIN/NOLOGIN
DANRY:X:1000:1000:DANRY:/HOME/DANRY:/BIN/BASH
SYSTEMD-BUS-PROXY:X:999:998:SYSTEMD BUS PROXY:/:/SBIN/NOLOGIN
SYSTEMD-NETWORK:X:998:997:SYSTEMD NETWORK MANAGEMENT:/:/SBIN/NOLOGIN
POLKITD:X:997:996:USER FOR POLKITD:/:/SBIN/NOLOGIN
UNBOUND:X:996:994:UNBOUND DNS RESOLVER:/ETC/UNBOUND:/SBIN/NOLOGIN
COLORD:X:995:993:USER FOR COLORD:/VAR/LIB/COLORD:/SBIN/NOLOGIN
GEOCLUE:X:994:991:USER FOR GEOCLUE:/VAR/LIB/GEOCLUE:/SBIN/NOLOGIN
SASLAUTH:X:993:76:SASLAUTHD USER:/RUN/SASLAUTHD:/SBIN/NOLOGIN
LIBSTORAGEMGMT:X:992:990:DAEMON ACCOUNT FOR LIBSTORAGEMGMT:/VAR/RUN/LSM:/SBIN/NOLOGIN
5.取出当前主机的IP地址，提示：对ifconfig命令的结果进行切分。
ifconfig | grep inet | grep -v 127.0.0.1 | head -1 | cut -d’ ‘ -f10
[root@localhost ~]# ifconfig | grep inet | grep -v 127.0.0.1 | head -1 | cut -d' ' -f10
192.168.1.1
[root@localhost ~]#
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。
ls /etc/*.conf | tr ‘a-z’ ‘A-Z’ > /tmp/etc.conf
[root@localhost ~]# ls /etc/*.conf | tr 'a-z' 'A-Z' > /tmp/etc.conf
[root@localhost ~]#
[root@localhost ~]# cat /tmp/etc.conf
/ETC/ASOUND.CONF
/ETC/AUTOFS.CONF
/ETC/AUTOFS_LDAP_AUTH.CONF
/ETC/BRLTTY.CONF
/ETC/CGCONFIG.CONF
/ETC/CGRULES.CONF
/ETC/CGSNAPSHOT_BLACKLIST.CONF
/ETC/CHRONY.CONF
/ETC/DLEYNA-SERVER-SERVICE.CONF
/ETC/DNSMASQ.CONF
/ETC/DRACUT.CONF
/ETC/E2FSCK.CONF
/ETC/FPRINTD.CONF
/ETC/FUSE.CONF
/ETC/HBA.CONF
/ETC/HOST.CONF
/ETC/IDMAPD.CONF
/ETC/IPSEC.CONF
/ETC/KDUMP.CONF
/ETC/KRB5.CONF
/ETC/KSMTUNED.CONF
/ETC/LD.SO.CONF
/ETC/LIBAUDIT.CONF
/ETC/LIBUSER.CONF
/ETC/LOCALE.CONF
/ETC/LOGROTATE.CONF
/ETC/MAN_DB.CONF
/ETC/MKE2FS.CONF
/ETC/MTOOLS.CONF
/ETC/NFSMOUNT.CONF
/ETC/NSSWITCH.CONF
/ETC/NTP.CONF
/ETC/NUMAD.CONF
/ETC/ODDJOBD.CONF
/ETC/PBM2PPA.CONF
/ETC/PNM2PPA.CONF
/ETC/RADVD.CONF
/ETC/REQUEST-KEY.CONF
/ETC/RESOLV.CONF
/ETC/RSYNCD.CONF
/ETC/RSYSLOG.CONF
/ETC/SESTATUS.CONF
/ETC/SOS.CONF
/ETC/SUDO.CONF
/ETC/SUDO-LDAP.CONF
/ETC/SYSCTL.CONF
/ETC/TCSD.CONF
/ETC/UPDATEDB.CONF
/ETC/USB_MODESWITCH.CONF
/ETC/VCONSOLE.CONF
/ETC/WVDIAL.CONF
/ETC/YUM.CONF
[root@localhost ~]#
7.显示/var目录下一级子目录或文件的总个数。
ls /var/ | wc -l
[root@localhost ~]# ls /var/ | wc -l
22
[root@localhost ~]#
[root@localhost ~]# ls /var/
account cache db games kerberos local log nis preserve spool tmp
adm crash empty gopher lib lock mail opt run target yp
[root@localhost ~]#
8.取出/etc/group 文件中的第三个字段最小的10个组的名字。
sort /etc/group -t ‘:’ -k3 -n | head -10
[root@localhost ~]# sort /etc/group -t ':' -k3 -n | head -10
root:x:0:
bin:x:1:
daemon:x:2:
sys:x:3:
adm:x:4:
tty:x:5:
disk:x:6:
lp:x:7:
mem:x:8:
kmem:x:9:
[root@localhost ~]#
9.讲/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。
(1),cat /etc/fstab > /tmp/etc.test , cat /etc/issue >> /tmp/etc.test
[root@localhost ~]# cat /etc/fstab > /tmp/etc.test
[root@localhost ~]# cat /etc/issue >> /tmp/etc.test
[root@localhost ~]# cat /tmp/etc.test
#
# /etc/fstab
# Created by anaconda on Tue Jul 11 07:26:54
#
# 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/centos-root / xfs defaults 0 0
UUID=d6b40b2e-f1d4-44d7-9f7d-603a0a6e13b5 /boot xfs defaults 0 0
/dev/mapper/centos-swap swap swap defaults 0 0
\S
Kernel \r on an \m
[root@localhost ~]#
(2),cat /etc/{fstab,issue} > /tmp/etc.test
[root@localhost ~]# rm -rf /tmp/etc.test
[root@localhost ~]# cat /etc/{fstab,issue} > /tmp/etc.test
[root@localhost ~]# cat /tmp/etc.test
#
# /etc/fstab
# Created by anaconda on Tue Jul 11 07:26:54
#
# 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/centos-root / xfs defaults 0 0
UUID=d6b40b2e-f1d4-44d7-9f7d-603a0a6e13b5 /boot xfs defaults 0 0
/dev/mapper/centos-swap swap swap defaults 0 0
\S
Kernel \r on an \m
[root@localhost ~]#
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联系：
(1)，创建distro，其中GID为；
groupadd -g distro
[root@localhost ~]# groupadd -g distro
[root@localhost ~]# tail -1 /etc/group
distro:x::
[root@localhost ~]#
(2)，创建用户mandriva，其中ID号为1005；基本组为distro；
useradd -g distro -u 1005 mandriva
[root@localhost ~]# useradd -g distro -u 1005 mandriva
[root@localhost ~]# tail -1 /etc/passwd
mandriva:x:1005:::/home/mandriva:/bin/bash
[root@localhost ~]#
(3)，创建用户mageia，其中ID号为1100，家目录为/home/linux;
useradd -u 1100 -1 /home/linux mageia
[root@localhost ~]# useradd -u 1100 -d /home/linux mageia
[root@localhost ~]# tail -1 /etc/passwd
mageia:x:1100:1100::/home/linux:/bin/bash
[root@localhost ~]#
(4)，给用户mageia添加密码，密码为mageedu；
echo mageedu | passwd –stdin mageia
[root@localhost ~]# echo mageedu | passwd --stdin mageia
Changing password for user mageia.
passwd: all authentication tokens updated successfully.
[root@localhost ~]#
(5)，删除mandriva，但保留其家目录；
userdel mandriva
[root@localhost ~]# userdel mandriva
[root@localhost ~]# ls /home/
danry linux mandriva
[root@localhost ~]# grep mandriva /etc/passwd
[root@localhost ~]#
(6)，创建用户slackware，其ID号为2002，基本组为distro，附加组peguin；
useradd -u 2002 -G distro,peguin slackware
[root@localhost ~]# useradd -u 2002 -G distro,peguin slackware
[root@localhost ~]# tail -1 /etc/passwd
slackware:x:2002:2002::/home/slackware:/bin/bash
[root@localhost ~]# id slackware
uid=2002(slackware) gid=2002(slackware) groups=2002(slackware),(distro),(peguin)
[root@localhost ~]#
(7)，修改slackware的默认shell为/bin/tosh;
usermod -s /bin/tcsh slackware
[root@localhost ~]# usermod -s /bin/tcsh slackware
[root@localhost ~]# id slackware
uid=2002(slackware) gid=2002(slackware) groups=2002(slackware),(distro),(peguin)
[root@localhost ~]# grep slackware /etc/passwd
slackware:x:2002:2002::/home/slackware:/bin/tcsh
[root@localhost ~]#
(8)，为用户slackware新增附加组admins；
[root@localhost ~]# usermod -G adminis slackware
[root@localhost ~]# id slackware
uid=2002(slackware) gid=2002(slackware) groups=2002(slackware),(adminis)
[root@localhost ~]#
原创文章，作者：N27_Danry，如若转载，请注明出处：/81613
