Content of this week's job:
1. List the user name of all logged-in users on the current system, note: The same user logged in multiple times, only once.
#who | tr-s [[: Space:]] | Cut-d ""-f1 | Sort-u
[email protected] bin]# who | tr-s [[: Space:]] | Cut-d ""-f1 | Sort-u
Kzxjwb
Root
2. Remove the information about the user who last logged in to the current system.
#last | Head-1
[Email protected] bin]# Last | Head-1
Root PTS/4 223.72.80.48 Mon Oct 23:07 still logged in
3. Remove the shell that is the user's default shell on the current system.
#cat/etc/passwd | Cut-d ":"-f7 | uniq-c | Sort-n | Tail-1 | tr-s [[: Space:]] | Cut-d ""-f3
[Email protected] webapps]# CAT/ETC/PASSWD | Cut-d ":"-f7 | uniq-c | Sort-n | Tail-1 | tr-s [[: Space:]] | Cut-d ""-f3
/sbin/nologin
4, the information of the third field in/ETC/PASSW D with the largest number of the first 10 users is changed to uppercase and then saved to the/tmp/maxusers.txt file.
[Email protected]/]# CAT/ETC/PASSWD | Sort-t ":"-nk3 | tail-10 | tr [A-z] [a-z] >/tmp/maxusers.txt
[Email protected]/]# Cat/tmp/maxusers.txt
User2:x:1024:1026::/home/user2:/bin/bash
User3:x:1025:1027::/home/user3:/bin/bash
User4:x:1026:1028::/home/user4:/bin/bash
User5:x:1027:1029::/home/user5:/bin/bash
User6:x:1028:1030::/home/user6:/bin/bash
User7:x:1029:1031::/home/user7:/bin/bash
User8:x:1030:1032::/home/user8:/bin/bash
User9:x:1031:1033::/home/user9:/bin/bash
User10:x:1032:1034::/home/user10:/bin/bash
User11:x:1033:1035::/home/user11:/bin/bash
5, take out the IP address of the current host, hint: The result of ifconfig command is sliced.
#ifconfig | Grep-e "inet addr" | Cut-d ":"-f2 | Cut-d ""-f1
6. List the file names of all files ending with. conf in/etc directory and convert their names to uppercase and save them to the/tmp/etc.conf file.
[Email protected]/]# ls/etc/*.conf | tr [A-z] [a-z] >/tmp/etc.conf
[Email protected]/]# cat/tmp/etc.conf
/etc/asound. CONF
/ETC/DNSMASQ. CONF
/etc/dracut. CONF
/etc/e2fsck. CONF
/etc/host. CONF
/etc/kdump. CONF
/etc/krb5. 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/nsswitch. CONF
/ETC/NTP. CONF
/etc/resolv. CONF
/etc/rsyslog. CONF
/etc/sestatus. CONF
/etc/sudo. CONF
/etc/sudo-ldap. CONF
/etc/sysctl. CONF
/ETC/TCSD. CONF
/etc/vconsole. CONF
/etc/yum. CONF
7. Displays the total number of sub-directories or files in the/var directory.
[Email protected]/]# Ll/var | Wc-l
22
8. Remove the names of the 10 groups with the smallest number of the third field in the/etc/group file.
[Email protected]/]# Cat/etc/group | Sort-t ":"-nk3 | head-10 | Cut-d ":"-f1
Root
Bin
Daemon
Sys
cd/
Tty
Disk
Lp
9, the contents of the/etc/fstab and/etc/issue files are merged into the same content and saved to the/tmp/etc.test file.
[Email protected]/]# cat/etc/fstab/etc/issue >/tmp/etc.test
[Email protected]/]# cat/tmp/etc.test
#
#/etc/fstab
# Created by Anaconda on Fri Mar 11 01:59:10 2016
#
# Accessible filesystems, by reference, is maintained under '/dev/disk '
# See mans Pages Fstab (5), Findfs (8), mount (8) and/or Blkid (8) for more info
#
UUID=E7EDF137-5D28-407F-98B9-804EAD7732B2/XFS Defaults 0 0
Uuid=6d3d5767-9a65-4f80-ae84-87d2c324edbd/boot XFS Defaults 0 0
Uuid=63a207f4-e7ae-4b27-87c5-f56054d49206/data XFS Defaults 0 0
Uuid=d0e6dd42-8f9c-4fba-b450-d068475fbb14/tmp XFS Defaults 0 0
UUID=9015AA16-40BD-46DB-8C6B-B019513A8111/USR XFS Defaults 0 0
UUID=DCBBA68B-953B-4CD5-9B92-88801EF89C0A swap swap defaults 0 0
\s
Kernel \ r on an \m
10. Summarize the methods used to describe the user and group management commands and complete the following exercises:
(1), create group distro, its GID is 2016;
[Email protected] ~]# groupadd-g distro
[Email protected] ~]# Cat/etc/group |tail-1
DISTRO:X:2016:
(2), create user Mandriva, whose ID number is 1005; basic group is distro;
[Email protected] ~]# useradd-u 1005-g distro Mandriva
Useradd:uid 1005 is not unique
[Email protected] ~]# useradd-u 1105-g distro Mandriva
[[email protected] ~]# ID Mandriva
uid=1105 (Mandriva) gid=2016 (distro) groups=2016 (distro)
(3), create user Mageia, whose ID number is 1100, home directory is/home/linux;
[Email protected] ~]# useradd-u 1100-d/home/linux Mageia
[Email protected] ~]# CAT/ETC/PASSWD | Tail-1
Mageia:x:1100:1100::/home/linux:/bin/bash
(4), to the user mageia add password, password for mageedu;
[Email protected] ~]# echo "mageedu" | Passwd–stdin Mageia
Passwd:only one user name may specified.
(5), delete Mandriva, but retain their home directory;
[Email protected] ~]# CAT/ETC/PASSWD | grep Mandriva
Mandriva:x:1105:2016::/home/mandriva:/bin/bash
[Email protected] ~]# Userdel Mandriva
(6), create user Slackware, its ID number is 2002, the basic group is distro, additional group Peguin;
[Email protected] ~]# Groupadd Peguin
[Email protected] ~]# useradd-u 2002-g distro-g Peguin Slackware
[[email protected] ~]# ID Slackware
uid=2002 (Slackware) gid=2016 (distro) groups=2016 (distro) (Peguin)
(7), modify the Slackware default shell for/BIN/TCSH;
[Email protected] ~]# CAT/ETC//PASSWD | Tail-1
Slackware:x:2002:2016::/home/slackware:/bin/bash
[Email protected] ~]# usermod-s/bin/tcsh Slackware
[Email protected] ~]# CAT/ETC/PASSWD | Tail-1
Slackware:x:2002:2016::/home/slackware:/bin/tcsh
[Email protected] ~]#
(8), add additional Group admins for user Slackware;
[Email protected] ~]# groupadd Admins
[Email protected] ~]# usermod-ag admins Slackware
[[email protected] ~]# ID Slackware
uid=2002 (Slackware) gid=2016 (distro) groups=2016 (distro), (Peguin), 2018 (admins)
(9), add password for Slackware, and require the minimum password age of 3 days, the maximum is 180 days, warning for 3 days;
[Email protected] ~]# echo Slackware | PASSWD–STDIN-N3-X180-W3 Slackware
Passwd:only one user name may specified.
[Email protected] ~]# Cat/etc/shadow | Tail-1
slackware:!! : 17098:0:99999:7:::
(10), add user OpenStack, whose ID number is 3003, the basic group is clouds, the additional group is Peguin and Nova;
Useradd-u 3003-g clouds-g Peguin OpenStack
(11), add the system user MySQL, request its shell for/sbin/nologin;
#useradd-R-s/sbin/nologin MySQL
(12), use the echo command, non-interactive add a password for OpenStack.
echo OpenStack | Passwd–stdin OpenStack &>/dev/null
This article is from the "9099360" blog, please be sure to keep this source http://9109360.blog.51cto.com/9099360/1865243
Linux OPS-3rd week jobs