Megeedu Linux+python Advanced Operations 3 period three weeks

1. List the user name of all logged-in users on the current system, note: The same user logged in multiple times, only once.

[Email protected] ~]# whoroot pts/0 2016-08-19 17:46 (172.16.168.16) root pts/1 2016-08-19 17:46 (17 2.16.168.16) [[email protected] ~]# who | Cut-d '-f1 | Uniq Root[[email protected] ~]#

2. Remove the information about the user who last logged in to the current system.

[[email protected] ~]# whoroot      pts/0        2016-08-19 17:46  (172.16.168.16) root      pts/1        2016-08-19 17:46  (172.16.168.16) root     pts/2         2016-08-19 17:53  (172.16.168.16) [[Email protected] ~]# who | tail -n  1root     pts/2        2016-08-19  17:53  (172.16.168.16) [[email protected] ~]# who | tail -n 1 |  cut -d  '    -f1 | iduid=0 (root)  gid=0   group =0 (root)   environment = unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023[[email protected] ~]# 

3. Remove the shell that is the user's default shell on the current system.

[Email protected] ~]# CAT/ETC/PASSWD | Cut-d ': '-f7 | uniq-c | Sort-n | Tail-n 1 11/sbin/nologin[[email protected] ~]#

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 -n -k 3 -t   ': '  | tr  ' A-Z '   ' A-Z '  >> /tmp/maxusers.txt      [[email protected] ~]# cat /tmp/maxusers.txt root:x:0:0:root:/root:/bin/bashbin : x:1:1:bin:/bin:/sbin/nologindaemon:x:2:2:daemon:/sbin:/sbin/nologinadm:x:3:4:adm:/var/adm:/sbin/nologinlp:x : 4:7:lp:/var/spool/lpd:/sbin/nologinsync:x:5:0:sync:/sbin:/bin/syncshutdown:x:6:0:shutdown:/sbin:/sbin/ shutdownhalt:x:7:0:halt:/sbin:/sbin/haltmail:x:8:12:mail:/var/spool/mail:/sbin/nologinuucp:x:10:14:uucp:/var/ spool/uucp:/sbin/nologinoperator:x:11:0:operator:/root:/sbin/nologingames:x:12:100:games:/usr/games:/sbin/ Nologingopher:x:13:30:gopher:/var/gopher:/sbin/nologinftp:x:14:50:ftp user:/var/ftp:/sbin/nologinvcsa:x : 69:69:virtual console memory owner:/dev:/sbin/nologinsshd:x:74:74:privilege-separated ssh :/var/empty/sshd:/sbin/nologinposTfix:x:89:89::/var/spool/postfix:/sbin/nologinnobody:x:99:99:nobody:/:/sbin/nologinsaslauth:x:499:76:saslauthd  user:/var/empty/saslauth:/sbin/nologin[[email protected] ~]#

5, take out the IP address of the current host, hint: The result of ifconfig command is sliced.

[Email protected] ~]# ifconfig eth0 | grep ' inet addr ' | Cut-d ': '-f2 | Cut-d '-f1172.16.168.9[[email protected] ~]#

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 | Cut-d '/'-f3 | Tr ' A-Z ' A-Z ' >/tmp/etc.conf [[email protected] ~]# cat/tmp/etc.conf dracut. Confgai. Confgrub. Confhost. Confinit. Confkdump. CONFKRB5. Confld. So. Conflibaudit. Conflibuser. Conflogrotate. Confmke2fs. Confnsswitch. Confresolv. Confrsyslog. Confsestatus. Confsudo. Confsudo-ldap. Confsysctl. Confyum. Conf[[email protected] ~]#

7. Displays the total number of sub-directories or files in the/var directory.

[[email protected] ~]# Ls/var/cache db Games l2e3d l3ed Lib lock mail opt run Tmpcrash empty l22d l333d Le3d local log NIS preserve spool yp[[email protected] ~]# ls/var/| Wc-l22[[email protected] ~]#

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-n-K 3-t ': ' | Head-n 10 | Cut-d ': '-f1rootbindaemonsysadmttydisklpmemkmem[[email protected] ~]#

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/fstab# created by  Anaconda on fri jul 29 07:03:27 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/ volgroup-lv_root /                        ext4    defaults         1 1UUID=5d921146-c901-4504-8266-21e100ccb7a3 /boot                    ext4     defaults        1 2/dev/mapper/volgroup-lv_home  /home                   ext4     defaults        1 2/dev/mapper/volgroup-lv_swap  swap                     swap    defaults        0  0tmpfs                    /dev/shm                 tmpfs   defaults        0 0devpts                   / Dev/pts                devpts   gid=5,mode=620  0 0sysfs                    /sys                     sysfs   defaults         0 0proc                     /proc                    proc    defaults         0 0[[email protected] ~]# cat /etc/issueCentOS  release 6.8  (Final) kernel \r on an \m[[email protected] ~]# cat  /etc/fstab /etc/issue >> /tmp/etc.test[[email protected] ~]# cat  /tmp/etc.test ## /etc/fstab# created by anaconda on fri jul 29 07:03:27 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/VolGroup-lv_root /                        ext4     defaults        1 1uuid= 5d921146-c901-4504-8266-21e100ccb7a3 /boot                    ext4    defaults         1 2/dev/mapper/VolGroup-lv_home /home                &nBsp;   ext4    defaults        1  2/dev/mapper/VolGroup-lv_swap swap                     swap    defaults         0 0tmpfs                    /dev/shm                 tmpfs   defaults         0 0devpts                   /dev/pts                 devpts  gid=5,mode=620  0 0sysfs                    /sys                     sysfs   defaults         0 0proc                     /proc                    proc     defaults        0 0CentOS release 6.8  (Final ) kernel \r on an \m[[email protected] ~]#

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

(2), create user Mandriva, whose ID number is 1005; basic group is distro;

[Email protected] ~]# useradd-u 1005-g distro Mandriva

(3), create user Mageia, whose ID number is 1100, home directory is/home/linux;

[Email protected] ~]# useradd-u 1100-d/home/linux Mageia

(4), to the user mageia add password, password for mageedu;

[Email protected] ~]# echo "mageedu" |passwd--stdin Mageia

(5), delete Mandriva, but retain their home directory;

[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

(7), modify the Slackware default shell for/BIN/TCSH;

[Email protected] ~]# usermod-s/bin/tcsh Slackware

(8), add additional Group admins for user Slackware;

[Email protected] ~]# groupadd Admins && usermod-g Admins slackware-a

(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] ~]# passwd slackware-n 3-x 180-w 3

(10), add user OpenStack, whose ID number is 3003, the basic group is clouds, the additional group is Peguin and Nova;

[[email protected] ~]# groupadd clouds[[email protected] ~]# groupadd nova[[email protected] ~]# useradd-u 3003-g clouds -G Peguin,nova openstack[[email protected] ~]#

(11), add the system user MySQL, request its shell for/sbin/nologin;

[Email protected] ~]# useradd-r mysql-s/sbin/nologin

(12), use the echo command, non-interactive add a password for OpenStack.

[Email protected] ~]# echo "123456" |passwd--stdin OpenStack

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Megeedu Linux+python Advanced Operations 3 period three weeks