1, the Replication/etc/skel directory is/home/tuser1, requires/home/tuser1 and its internal files belong to the group and other users do not have any access rights.
[Email protected] home]# cp-r/etc/skel//home/tuser1
[Email protected] home]# chmod-r u-r,o-r tuser1/
[email protected] home]# LL
Total 40
DRWX------. 2 bash bash 4096 12:01 bash
DRWX------. 2 basher basher 4096 12:01 basher
DRWX------. 2 Mageia mageia 4096 01:14 Linux
DRWX------. 2 1005 distro 4096 01:12 Mandriva
DRWX------. 2 nologin nologin 4096 12:01 Nologin
DRWX------. 2 OpenStack clouds 4096 01:50 OpenStack
DRWX------. 2 Slackware distro 4096 01:24 Slackware
DRWX------. 2 Testbash testbash 4096 12:01 Testbash
D-wxr-x--x. 2 root root 4096 13:58 Tuser1
DRWX------. 2 Zengzy zengzy 4096 08:28 Zengzy
[email protected] home]# su Zengzy
[Email protected] home]$ cd/home/tuser1/
[[email protected] tuser1]$ ls
Ls:cannot Open Directory.: Permission denied
2. Edit the/etc/group file and add the group Hadoop.
[Email protected] home]# Vim/etc/group
[Email protected] home]# tail-n 5/etc/group
Admins:x:2018:slackware
CLOUDS:X:2019:
Nova:x:2020:openstack
mysql:x:498:
hadoop:x:499:
[Email protected] home]# echo ' hadoop1:x:505: ' >>/etc/group
[Email protected] home]# tail-n 1/etc/group
hadoop1:x:505:
3. Manually edit the/etc/passwd file to add a new line, adding user Hadoop, whose basic group ID is the Hadoop group ID number; its home directory is/home/hadoop.
[Email protected] home]# VIM/ETC/PASSWD
Hadoop:x:505:499::/home/hadoop:/bin/bash
[[email protected] home]# ID Hadoop
uid=505 (Hadoop) gid=499 (Hadoop) groups=499 (Hadoop)
[[email protected] home]# echo ' Hadoop1:x:506:505::/home/hadpood1:/bin/bash ' >>/etc/passwd
[[email protected] home]# ID HADOOP1
uid=506 (HADOOP1) gid=505 (HADOOP1) groups=505 (HADOOP1)
4. Copy the/etc/skel directory as/home/hadoop, which requires that the genus Group and other users of the Hadoop directory be modified without any access rights.
[Email protected] home]# cp-r/etc/skel/home/hadoop
[email protected] home]# LL
Total 44
DRWX------. 2 bash bash 4096 12:01 bash
DRWX------. 2 basher basher 4096 12:01 basher
Drwxr-xr-x. 2 root root 4096 14:22 Hadoop
DRWX------. 2 Mageia mageia 4096 01:14 Linux
DRWX------. 2 1005 distro 4096 01:12 Mandriva
DRWX------. 2 nologin nologin 4096 12:01 Nologin
DRWX------. 2 OpenStack clouds 4096 01:50 OpenStack
DRWX------. 2 Slackware distro 4096 01:24 Slackware
DRWX------. 2 Testbash testbash 4096 12:01 Testbash
D-wxr-x--x. 2 root root 4096 13:58 Tuser1
DRWX------. 2 Zengzy zengzy 4096 08:28 Zengzy
[Email protected] home]# chmod g-r,o-r hadoop/
[email protected] home]# LL
Total 44
DRWX------. 2 bash bash 4096 12:01 bash
DRWX------. 2 basher basher 4096 12:01 basher
Drwx--x--x. 2 root root 4096 14:22 Hadoop
DRWX------. 2 Mageia mageia 4096 01:14 Linux
DRWX------. 2 1005 distro 4096 01:12 Mandriva
DRWX------. 2 nologin nologin 4096 12:01 Nologin
DRWX------. 2 OpenStack clouds 4096 01:50 OpenStack
DRWX------. 2 Slackware distro 4096 01:24 Slackware
DRWX------. 2 Testbash testbash 4096 12:01 Testbash
D-wxr-x--x. 2 root root 4096 13:58 Tuser1
DRWX------. 2 Zengzy zengzy 4096 08:28 Zengzy
5, modify the/home/hadoop directory and all the internal files of the owner of Hadoop, belong to Hadoop group.
[email protected] home]# LL
Total 44
DRWX------. 2 bash bash 4096 12:01 bash
DRWX------. 2 basher basher 4096 12:01 basher
Drwx--x--x. 2 root root 4096 14:22 Hadoop
DRWX------. 2 Mageia mageia 4096 01:14 Linux
DRWX------. 2 1005 distro 4096 01:12 Mandriva
DRWX------. 2 nologin nologin 4096 12:01 Nologin
DRWX------. 2 OpenStack clouds 4096 01:50 OpenStack
DRWX------. 2 Slackware distro 4096 01:24 Slackware
DRWX------. 2 Testbash testbash 4096 12:01 Testbash
D-wxr-x--x. 2 root root 4096 13:58 Tuser1
DRWX------. 2 Zengzy zengzy 4096 08:28 Zengzy
[Email protected] home]# chown-r hadoop:hadoop hadoop/
[email protected] home]# LL
Total 44
DRWX------. 2 bash bash 4096 12:01 bash
DRWX------. 2 basher basher 4096 12:01 basher
Drwx--x--x. 2 Hadoop hadoop 4096 14:22 Hadoop
DRWX------. 2 Mageia mageia 4096 01:14 Linux
DRWX------. 2 1005 distro 4096 01:12 Mandriva
DRWX------. 2 nologin nologin 4096 12:01 Nologin
DRWX------. 2 OpenStack clouds 4096 01:50 OpenStack
DRWX------. 2 Slackware distro 4096 01:24 Slackware
DRWX------. 2 Testbash testbash 4096 12:01 Testbash
D-wxr-x--x. 2 root root 4096 13:58 Tuser1
DRWX------. 2 Zengzy zengzy 4096 08:28 Zengzy
6. Display the lines in the/proc/meminfo file beginning with uppercase or lowercase s, in two ways;
[Email protected] home]# Cat/proc/meminfo | grep "^[ss]"
swapcached:0 KB
swaptotal:2097148 KB
swapfree:2097148 KB
shmem:236 KB
slab:106148 KB
sreclaimable:46064 KB
sunreclaim:60084 KB
[Email protected] home]# Cat/proc/meminfo | Grep-i "^s"
swapcached:0 KB
swaptotal:2097148 KB
swapfree:2097148 KB
shmem:236 KB
slab:106144 KB
sreclaimable:46060 KB
sunreclaim:60084 KB
7. Display/ETC/PASSW D file whose default shell is non-/sbin/nologin user;
[Email protected] home]# CAT/ETC/PASSWD | Grep-v "/sbin/nologin$" | Cut-d:-f1
Root
Sync
Shutdown
Halt
Zengzy
Bash
Basher
Testbash
Mageia
Slackware
OpenStack
Hadoop
Hadoop1
8. Display the user whose default shell is/bin/bash in/ETC/PASSW D file;
[Email protected] home]# CAT/ETC/PASSWD | grep "/bin/bash$" | Cut-d:-f1
Root
Zengzy
Bash
Basher
Testbash
Mageia
OpenStack
Hadoop
Hadoop1
9. Find out one or two digits in/ETC/PASSW D file;
[Email protected] home]# egrep "\<[0-9]{1,2}\>"/etc/passwd
Root:x:0:0:root:/root:/bin/bash
Bin:x:1:1:bin:/bin:/sbin/nologin
Daemon:x:2:2:daemon:/sbin:/sbin/nologin
Adm:x:3:4:adm:/var/adm:/sbin/nologin
Lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin
Sync:x:5:0:sync:/sbin:/bin/sync
Shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
Halt:x:7:0:halt:/sbin:/sbin/halt
Mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
Uucp:x:10:14:uucp:/var/spool/uucp:/sbin/nologin
Operator:x:11:0:operator:/root:/sbin/nologin
Games:x:12:100:games:/usr/games:/sbin/nologin
Gopher:x:13:30:gopher:/var/gopher:/sbin/nologin
Ftp:x:14:50:ftp User:/var/ftp:/sbin/nologin
Nobody:x:99:99:nobody:/:/sbin/nologin
Vcsa:x:69:69:virtual Console Memory Owner:/dev:/sbin/nologin
SASLAUTH:X:499:76:SASLAUTHD User:/var/empty/saslauth:/sbin/nologin
Postfix:x:89:89::/var/spool/postfix:/sbin/nologin
Sshd:x:74:74:privilege-separated Ssh:/var/empty/sshd:/sbin/nologin
[[email protected] home]# grep--color=auto "\<[0-9]\{1,2\}\>"/etc/passwd
Root:x:0:0:root:/root:/bin/bash
Bin:x:1:1:bin:/bin:/sbin/nologin
Daemon:x:2:2:daemon:/sbin:/sbin/nologin
Adm:x:3:4:adm:/var/adm:/sbin/nologin
Lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin
Sync:x:5:0:sync:/sbin:/bin/sync
Shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
Halt:x:7:0:halt:/sbin:/sbin/halt
Mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
Uucp:x:10:14:uucp:/var/spool/uucp:/sbin/nologin
Operator:x:11:0:operator:/root:/sbin/nologin
Games:x:12:100:games:/usr/games:/sbin/nologin
Gopher:x:13:30:gopher:/var/gopher:/sbin/nologin
Ftp:x:14:50:ftp User:/var/ftp:/sbin/nologin
Nobody:x:99:99:nobody:/:/sbin/nologin
Vcsa:x:69:69:virtual Console Memory Owner:/dev:/sbin/nologin
SASLAUTH:X:499:76:SASLAUTHD User:/var/empty/saslauth:/sbin/nologin
Postfix:x:89:89::/var/spool/postfix:/sbin/nologin
Sshd:x:74:74:privilege-separated Ssh:/var/empty/sshd:/sbin/nologin
10. Display the line beginning with at least one blank character in/boot/grub/grub.conf;
[[email protected] home]# grep "^[[:space:]]\+"/boot/grub/grub.conf
Root (hd0,0)
kernel/vmlinuz-2.6.32-642.4.2.el6.x86_64 ro Root=uuid=b175aee5-62ee-4625-8aac-f3c455133efa Rd_NO_LUKS Rd_NO_LVM Lang=en_us. UTF-8 rd_no_md sysfont=latarcyrheb-sun16 crashkernel=auto keyboardtype=pc keytable=us Rd_NO_DM rhgb quiet
Initrd/initramfs-2.6.32-642.4.2.el6.x86_64.img
Root (hd0,0)
kernel/vmlinuz-2.6.32-642.el6.x86_64 ro Root=uuid=b175aee5-62ee-4625-8aac-f3c455133efa Rd_NO_LUKS rd_NO_LVM LANG=en _us. UTF-8 rd_no_md sysfont=latarcyrheb-sun16 crashkernel=auto keyboardtype=pc keytable=us Rd_NO_DM rhgb quiet
Initrd/initramfs-2.6.32-642.el6.x86_64.img
11, the display/etc/rc.d/rc.sysinit file with the beginning of #, followed by at least one white space character, and then have at least one non-whitespace character line;
[[email protected] home]# grep "^#[[:space:]]\+[^[:space:]]\+"/etc/rc.d/rc.sysinit
12, the Netstat-tan command execution results in the "LISTEN", followed by or with a blank character end of the line;
[Email protected] home]# Netstat-tan | Egrep "listten| [[: space:]]$]
Proto recv-q send-q Local address Foreign address state
TCP 0 0 0.0.0.0:22 0.0.0.0:* LISTEN
TCP 0 0 127.0.0.1:25 0.0.0.0:* LISTEN
TCP 0 192.168.2.105:22 192.168.2.106:12341 established
TCP 0 0 192.168.2.105:22 192.168.2.106:3099 established
TCP 0 0::: $:::* LISTEN
TCP 0 0:: 1:25:::* LISTEN
13, add user bash, Testbash, basher, Nologin (this one user's shell is/sbin/nologin), and then find the current system on its user name and the default shell of the same user information;
[Email protected] home]# Useradd bash
[Email protected] home]# Useradd Tetstbash
[Email protected] home]# Useradd basher
[Email protected] home]# useradd-s/sbin/nologin nologin
[[email protected] home]# 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:501:501::/home/bash:/bin/bash
nologin: x:504:504::/home/nologin:/sbin/nologin
This article comes from the "Recharge yourself" blog, so be sure to keep this source http://zengzeyang.blog.51cto.com/6129531/1842811
Marco Linux after-school assignment 4