linux-practice(1-19)
1、了解GPL(v1、v2、v3)、LGPL、Apache、BSD、MIT等開源協定的具體內容。
答：
BSD：不允許用作者名字打廣告，可商業化
Apache Licence2.0：註明修改處，可商業化
GPL：開源、免費。禁止商業化
LGPL：適合作為第三方類庫，可商業化
2、使用echo如何顯示“The year is 2017.\nToday is monday”為兩行？
答：
[root@little ~]# echo -e "The year is 2017.\nToday is monday"
The year is 2017.
Today is monday
3、使用printf命令如何顯示“ling little”為兩行？
答：
[root@little ~]# printf "ling\nlittle\n"
ling
little
4、通過man獲得幫助，創建目錄(如有精力，可以嘗試只使用一次mkdir命令解決此問題)
(1)在/mnt下創建boot和sysroot；
(2)在/mnt/boot下創建grub；
(3)在/mnt/sysroot下創建proc, sys, bin, sbin, lib, usr, var, etc, dev, home, root, tmp
a)在/mnt/sysroot/usr下創建bin, sbin, lib
b)在/mnt/sysroot/lib下創建modules
c)在/mnt/sysroot/var下創建run, log, lock
d)在/mnt/sysroot/etc下創建init.d
答：
[root@little ~]# mkdir -pv /mnt/{boot/grub,sysroot/{proc,sys,bin,sbin,lib/modules,lib64,usr/{bin,sbin/lib},var/{run,log,lock},etc/init.d,dev,home,root,tmp}}
mkdir: 已創建目錄 "/mnt/boot"
mkdir: 已創建目錄 "/mnt/boot/grub"
mkdir: 已創建目錄 "/mnt/sysroot"
mkdir: 已創建目錄 "/mnt/sysroot/proc"
mkdir: 已創建目錄 "/mnt/sysroot/sys"
mkdir: 已創建目錄 "/mnt/sysroot/bin"
mkdir: 已創建目錄 "/mnt/sysroot/sbin"
mkdir: 已創建目錄 "/mnt/sysroot/lib"
mkdir: 已創建目錄 "/mnt/sysroot/lib/modules"
mkdir: 已創建目錄 "/mnt/sysroot/lib64"
mkdir: 已創建目錄 "/mnt/sysroot/usr"
mkdir: 已創建目錄 "/mnt/sysroot/usr/bin"
mkdir: 已創建目錄 "/mnt/sysroot/usr/sbin"
mkdir: 已創建目錄 "/mnt/sysroot/usr/sbin/lib"
mkdir: 已創建目錄 "/mnt/sysroot/var"
mkdir: 已創建目錄 "/mnt/sysroot/var/run"
mkdir: 已創建目錄 "/mnt/sysroot/var/log"
mkdir: 已創建目錄 "/mnt/sysroot/var/lock"
mkdir: 已創建目錄 "/mnt/sysroot/etc"
mkdir: 已創建目錄 "/mnt/sysroot/etc/init.d"
mkdir: 已創建目錄 "/mnt/sysroot/dev"
mkdir: 已創建目錄 "/mnt/sysroot/home"
mkdir: 已創建目錄 "/mnt/sysroot/root"
mkdir: 已創建目錄 "/mnt/sysroot/tmp"
5、創建目錄/backup
復制目錄/etc至/backup目錄中，要求保留文件原來的屬性，保持鏈接文件；
答：
[root@little ~]# mkdir -pv /backup
mkdir: 已創建目錄 "/backup"
[root@little ~]# mv /etc /backup
[root@little ~]# echo $?
0
[root@little ~]# ls /backup/
etc
3、通過man幫助手冊，自行總結which、whereis、whatis命令的使用方法；
答：
which：命令的別名
whereis：命令的路徑
whatis：命令作用
[root@little ~]# which ls
alias ls=‘ls --color=auto‘
/bin/ls
[root@little ~]# whereis ls
ls: /bin/ls /usr/share/man/man1p/ls.1p.gz /usr/share/man/man1/ls.1.gz
4、通過幫助手冊，學習使用du命令；並思考：如何顯示某個目錄內部的所有文件的整體大小？
答：
du：顯示目錄大小
[root@little ~]# du
12 ./test
36 ./apr-util-1.5.4/hooks/.libs
88 ./apr-util-1.5.4/hooks
88 ./apr-util-1.5.4/memcache/.libs
228 ./apr-util-1.5.4/memcache
……
[root@little ~]# du ./test
12 ./test
5、通過幫助手冊，學習who、w、whoami命令，並對比who和w，思考其區別；
答：
who：登錄用戶
w：顯示用戶信息，更加詳細
whoami：顯示ID為0的用戶信息
[root@little ~]# who
little tty1 2017-11-13 13:27 (:0)
root pts/0 2017-11-13 13:29 (172.16.1.1)
[root@little ~]# w
13:51:50 up 25 min, 2 users, load average: 0.01, 0.01, 0.00
USER TTY FROM LOGIN@ IDLE JCPU PCPU WHAT
[root@little ~]# whoami
whoami：無法找到用戶ID 為0 的用戶名
6、顯示/etc目錄下，以字母開頭，後面跟了一個非字母及其它任意長度任意字符的文件或目錄；
答：
[root@little ~]# ls /etc | grep "^[[:alpha:]][^[:alpha:]].*"
X11
[root@little ~]# ls -d /etc/[[:alpha:]][^[:alpha:]]*
/etc/X11
7、顯示/usr/share/man目錄下，所有以man開頭，後跟一個數字結尾的文件或目錄；
答：
[root@little ~]# ls -d /usr/share/man/man[0-9]
/usr/share/man/man1 /usr/share/man/man4 /usr/share/man/man7
/usr/share/man/man2 /usr/share/man/man5 /usr/share/man/man8
/usr/share/man/man3 /usr/share/man/man6 /usr/share/man/man9
[root@little ~]#
[root@little ~]# ls -d /usr/share/man/man[[:digit:]]
/usr/share/man/man1 /usr/share/man/man4 /usr/share/man/man7
/usr/share/man/man2 /usr/share/man/man5 /usr/share/man/man8
/usr/share/man/man3 /usr/share/man/man6 /usr/share/man/man9
8、復制/etc目錄下，所以p,m,r開頭的，且以.conf結尾的文件或目錄至/tmp/conf.d目錄下；
答：
[root@little ~]# ls /etc/[pmr]*.conf
/etc/mke2fs.conf /etc/pnm2ppa.conf /etc/request-key.conf
/etc/mtools.conf /etc/prelink.conf /etc/resolv.conf
/etc/pbm2ppa.conf /etc/readahead.conf /etc/rsyslog.conf
/etc/pm-utils-hd-apm-restore.conf /etc/reader.conf
[root@little ~]#
[root@little ~]# cp -a /etc/[pmr]*.conf /tmp
[root@little ~]#
[root@little ~]# ls /tmp
keyring-Hw528X keyring-rjErX0 pnm2ppa.conf
keyring-KphV2t keyring-sNGWZe prelink.conf
keyring-NtnoIW keyring-seupBP pulse-CCOJSbg2rrUT
keyring-SD8DuM keyring-va5YXr pulse-kxE14xec0BgA
keyring-SWLHv8 keyring-w9r8Y2 pulse-nMz1VNv72M1x
keyring-Ta3gEf keyring-yT4OZn readahead.conf
keyring-akJZHb mke2fs.conf reader.conf
keyring-dFQOvC mtools.conf request-key.conf
keyring-g403YF orbit-gdm resolv.conf
keyring-hosyK7 orbit-little rsyslog.conf
keyring-hpmuXh pbm2ppa.conf virtual-little.QpKRpK
keyring-rEePKI pm-utils-hd-apm-restore.conf virtual-little.hPZ8F7
9、創建a123, cd6, c78m, c1 my, m.z, k 67, 8yu, 789等文件，並按照下述要求寫出相應的命令；
註意，以上文件是以逗號隔開的，其它符號都是文件名的組成部分；
1) 顯示所有以a或m開頭的文件；
2) 顯示所有文件名中包含了數字的文件；
3) 顯示所有以數字結尾且文件名中包含空白字符的文件；
4) 顯示文件名中不以c字母開頭並且不以數字結尾的所有文件；
答：
錯誤創建如下：（空格將其分開，產生錯誤）
[root@little ~]# touch {a123,cd6,c78m,c1 my,m.z,k 67,8yu,789}
[root@little ~]#
[root@little ~]# ls
2.txt cdrom //my,m.z,k ????????? ??????
3.txt dest t1file.txt ?????? ??????
//67,8yu,789} install.log zhengshu ??????
anaconda-ks.cfg install.log.syslog //{a123,cd6,c78m,c1 ??????
boot.iso ks.cfg ?????? ??????
正確創建如下：（處理空格，註釋掉空格）
[root@little ~]# touch {a123,cd6,c78m,‘c1 my‘,m.z,‘k 67‘,8yu,789}
[root@little ~]#
[root@little ~]# ls
2.txt anaconda-ks.cfg cdrom ks.cfg ????????? ??????
3.txt boot.iso dest m.z ?????? ??????
789 c1 my install.log t1file.txt ??????
8yu c78m install.log.syslog zhengshu ??????
a123 cd6 k 67 ?????? ??????
1)、
[root@little ~]# ls [am]*
a123 anaconda-ks.cfg m.z
2)、
[root@little ~]# ls *[0-9]*
2.txt 3.txt 789 8yu a123 c1 my c78m cd6 k 67 t1file.txt
3)、
[root@little ~]# ls *[[:space:]]*[0-9]
k 67
4)、
[root@little ~]# ls ^c*[^[:digit:]]
ls: cannot access ^c*[^[:digit:]]: No such file or directory
[root@little ~]#
[root@little ~]# ls [^c]*[^[:digit:]]
2.txt 8yu boot.iso install.log.syslog m.z
3.txt anaconda-ks.cfg install.log ks.cfg t1file.txt
10、統計/usr/bin/目錄下的文件個數；
答：
[root@little ~]# ls /usr/bin | wc -l
1940
11、取出/etc/passwd文件中第9至第15個用戶的信息，並將其保存至/tmp/users文件中；
答：
[root@little ~]# head -n 15 /etc/passwd | tail -n 7 > /tmp/users
[root@little ~]#
[root@little ~]# cat /tmp/users
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
12、顯示/etc目錄下所有以.conf結尾的文件或目錄，並統計其個數。
答：
[root@little ~]# ls /etc/*.conf
/etc/Trolltech.conf /etc/nfsmount.conf
/etc/asound.conf /etc/nsswitch.conf
/etc/autofs.conf /etc/ntp.conf
/etc/autofs_ldap_auth.conf /etc/oddjobd.conf
/etc/cas.conf /etc/openct.conf
/etc/dnsmasq.conf /etc/pbm2ppa.conf
/etc/dracut.conf /etc/pm-utils-hd-apm-restore.conf
/etc/fprintd.conf /etc/pnm2ppa.conf
/etc/gai.conf /etc/prelink.conf
/etc/grub.conf /etc/readahead.conf
/etc/gssapi_mech.conf /etc/reader.conf
/etc/hba.conf /etc/request-key.conf
/etc/host.conf /etc/resolv.conf
/etc/idmapd.conf /etc/rsyslog.conf
/etc/kdump.conf /etc/sestatus.conf
/etc/krb5.conf /etc/smartd.conf
/etc/latrace.conf /etc/sos.conf
/etc/ld.so.conf /etc/sudo-ldap.conf
/etc/libaudit.conf /etc/sudo.conf
/etc/libuser.conf /etc/sysctl.conf
/etc/logrotate.conf /etc/updatedb.conf
/etc/ltrace.conf /etc/warnquota.conf
/etc/mke2fs.conf /etc/yp.conf
/etc/mtools.conf /etc/yum.conf
/etc/named.conf
[root@little ~]#
[root@little ~]# ls /etc/*.conf | wc -l
49
13、把/etc/passwd文件最後三行信息中所有小寫字符改為大寫，並且刪除所有的":"、"/"以及數字字符；
答：
[root@little ~]# cat /etc/passwd | tail -n 3
little:x:500:500:little:/home/little:/bin/bash
mysql:x:27:27:MySQL Server:/var/lib/mysql:/bin/bash
named:x:25:25:Named:/var/named:/sbin/nologin
[root@little ~]#
[root@little ~]# cat /etc/passwd | tail -n 3 | tr a-z A-Z
LITTLE:X:500:500:LITTLE:/HOME/LITTLE:/BIN/BASH
MYSQL:X:27:27:MYSQL SERVER:/VAR/LIB/MYSQL:/BIN/BASH
NAMED:X:25:25:NAMED:/VAR/NAMED:/SBIN/NOLOGIN
[root@little ~]#
[root@little ~]# cat /etc/passwd | tail -n 3 | tr a-z A-Z | tr -d "‘:‘;‘/‘;[0-9]"
LITTLEXLITTLEHOMELITTLEBINBASH
MYSQLXMYSQL SERVERVARLIBMYSQLBINBASH
NAMEDXNAMEDVARNAMEDSBINNOLOGIN
14、取出/etc/fstab的第6行； //註意，空行也算一行
答：
[root@little ~]# cat /etc/fstab | head -n 6 | tail -n 1
# Accessible filesystems, by reference, are maintained under ‘/dev/disk‘
15、取出/etc目錄下所有以s開頭的文件或目錄，將其中最前面的8個文件保存到/tmp/start_with_s.out並同時進行標準輸出；
答：
[root@little ~]# ls -d /etc/s*
/etc/samba /etc/shadow /etc/statetab.d
/etc/sane.d /etc/shadow- /etc/sudo-ldap.conf
/etc/sasl2 /etc/shells /etc/sudo.conf
/etc/scl /etc/skel /etc/sudoers
/etc/securetty /etc/smartd.conf /etc/sudoers.d
/etc/security /etc/sos.conf /etc/sysconfig
/etc/selinux /etc/sound /etc/sysctl.conf
/etc/services /etc/ssh /etc/system-release
/etc/sestatus.conf /etc/ssl /etc/system-release-cpe
/etc/setuptool.d /etc/sssd
/etc/sgml /etc/statetab
[root@little ~]#
[root@little ~]# ls -d /etc/s* | head -8
/etc/samba
/etc/sane.d
/etc/sasl2
/etc/scl
/etc/securetty
/etc/security
/etc/selinux
/etc/services
[root@little ~]# ls -d /etc/s* | head -8 > /tmp/start_with_s.out
[root@little ~]#
[root@little ~]# cat /tmp/start_with_s.out
/etc/samba
/etc/sane.d
/etc/sasl2
/etc/scl
/etc/securetty
/etc/security
/etc/selinux
/etc/services
16、將目錄/etc備份至/backup目錄中，並重命名為“etc-當前日期_當前時間”，如etc-2013-02-26_20:46:30；要求保留文件原來的屬性，保持鏈接文件；
答：
[root@little ~]# cp -a /etc /backup/etc-2017-11-15_16:43:00
cp: cannot create directory `/backup/etc-2017-11-15_16:43:00‘: No such file or directory
[root@little ~]# mkdir /backup
[root@little ~]# ls /
backup boot etc lib lost+found misc net proc sbin srv tmp var
bin dev home lib64 media mnt opt root selinux sys usr
[root@little ~]# cp -a /etc /backup/etc-2017-11-15_16:43:00
[root@little ~]#
[root@little ~]# ls /backup/
etc-2017-11-15_16:43:00
17、使用touch命令基於花括號展開的方式創建如下文件：ace acf acg ade adf adg bce bcf bcg bde bdf bdg
答：
[root@little ~]# touch {a,b}{c,d}{e,f,g}
[root@little ~]# ls
2.txt acf bce boot.iso install.log zhengshu ??????
3.txt acg bcf c1 my install.log.syslog ?????? ??????
789 ade bcg c78m k 67 ????????? ??????
8yu adf bde cd6 ks.cfg ??????
a123 adg bdf cdrom m.z ??????
ace anaconda-ks.cfg bdg dest t1file.txt ??????
18、創建用戶xiaoding，使用centos和varnish作為附屬組，並將其家目錄設置於/ysu；使用xiaoding用戶登錄到系統，在其家目錄中創建名為projects的目錄，並在該目錄中創建demand、design、plan、project、report_bugs等文件。後來出於統一管理需要，再將其家目錄遷移至/home/ysu目錄中；
答：
[root@little ~]# groupadd centos
[root@little ~]# groupadd varnish
[root@little ~]# tail -2 /etc/group
centos:x:501:
varnish:x:502:
[root@little ~]# useradd xiaoding -G centos,varnish -d /ysu
[root@little ~]#
[root@little ~]# echo "18716022695" | passwd --stdin xiaoding
Changing password for user xiaoding.
passwd: all authentication tokens updated successfully.
[root@little ~]#
[root@little ~]# tail -3 /etc/group
centos:x:501:xiaoding
varnish:x:502:xiaoding
xiaoding:x:503:
[root@little ~]# id xiaoding
uid=501(xiaoding) gid=503(xiaoding) groups=503(xiaoding),501(centos),502(varnish)
[root@little ~]#
[root@little ~]# su - xiaoding
-bash: warning: setlocale: LC_CTYPE: cannot change locale (en_CN.UTF-8): No such file or directory
-bash: warning: setlocale: LC_COLLATE: cannot change locale (en_CN.UTF-8): No such file or directory
-bash: warning: setlocale: LC_MESSAGES: cannot change locale (en_CN.UTF-8): No such file or directory
-bash: warning: setlocale: LC_NUMERIC: cannot change locale (en_CN.UTF-8): No such file or directory
-bash: warning: setlocale: LC_TIME: cannot change locale (en_CN.UTF-8): No such file or directory
[xiaoding@little ~]$
[xiaoding@little ~]$ ls
[xiaoding@little ~]$
[xiaoding@little ~]$ mkdir -pv projects
mkdir: created directory `projects‘
[xiaoding@little ~]$ ls
projects
[xiaoding@little ~]$ touch projects/{demand,design,plan,project,report_bugs}
[xiaoding@little ~]$ ls projects/
demand design plan project report_bugs
[xiaoding@little ~]$
19、以下所有命令均為使用ling用戶登錄後，臨時以root用戶的身份完成，命令執行成功之後立即返回ling用戶環境；
1)創建用戶gentoo，UID為5000，基本組為centos，附加組為distro和peguin；
2)創建用戶fedora，其全名為"Fedora Core"，附加組為distro和peguin，默認shell為/bin/tcsh；
3)將用戶gentoo的附加組修改為bin和root，默認shell為/bin/csh，註釋信息為"Gentoo Distribution"；
4)為用戶fedora添加新的附屬組centos，使得其隸屬於四個組中；
5)創建系統用戶iscsi，指定其UID為808，其主組是GID為808的系統組mydisk，並使其不可交互登錄系統，且不為其創建家目錄；
6)由於gentoo用戶出差一個月，所以直到其回公司之前，禁止其登錄系統，你有幾種方式解決此問題？請盡可能多的寫出來。
答：
（6）：
1)：# usermod -L gentoo
2): # passwd -l gentoo
//用來鎖賬戶
3): # vim /etc/shadow
gentoo:!$6$ata(fd$adfa
4): # usermod -s /sbin/nologin gentoo
5): # chsh -s /sbin/nologin gentoo
//改變登錄shell
6): # usermod -e 2017-02-04 gentoo
答：
[root@little ~]# groupadd distro;groupadd peguin
[root@little ~]#
[root@little ~]# tail -2 /etc/group
distro:x:505:
peguin:x:506:
[root@little ~]#
[root@little ~]# useradd gentoo -u 5000 -g centos -G distro,peguin
[root@little ~]# tail -3 /etc/group
ling:x:504:
distro:x:505:gentoo
peguin:x:506:gentoo
[root@little ~]# echo "18716022695" | passwd --stdin gentoo
Changing password for user gentoo.
passwd: all authentication tokens updated successfully.
[root@little ~]#
[root@little ~]# tail -1 /etc/passwd
gentoo:x:5000:501::/home/gentoo:/bin/bash
[root@little ~]#
[root@little ~]# tail -5 /etc/group
varnish:x:502:xiaoding
xiaoding:x:503:
ling:x:504:
distro:x:505:gentoo
peguin:x:506:gentoo
[root@little ~]#
[root@little ~]# id gentoo
uid=5000(gentoo) gid=501(centos) groups=501(centos),505(distro),506(peguin)
[root@little ~]#
[root@little ~]# useradd fedora -c "Fedora Core" -G distro,peguin -s /bin/tcsh
[root@little ~]#
[root@little ~]# echo "18716022695" | passwd --stdin fedora
Changing password for user fedora.
passwd: all authentication tokens updated successfully.
[root@little ~]#
[root@little ~]# tail -1 /etc/passwd
fedora:x:5001:5001:Fedora Core:/home/fedora:/bin/tcsh
[root@little ~]# tail -3 /etc/group
distro:x:505:gentoo,fedora
peguin:x:506:gentoo,fedora
fedora:x:5001:
[root@little ~]# id fedora
uid=5001(fedora) gid=5001(fedora) groups=5001(fedora),505(distro),506(peguin)
[root@little ~]#
[root@little ~]# useradd -G bin,root -s /bin/csh -c "Gentoo Distribution" gentoouseradd: user ‘gentoo‘ already exists
[root@little ~]#
[root@little ~]# id gentoo
uid=5000(gentoo) gid=501(centos) groups=501(centos),505(distro),506(peguin)
[root@little ~]#
[root@little ~]# usermod -aG centos fedora
[root@little ~]#
[root@little ~]# id fedora
uid=5001(fedora) gid=5001(fedora) groups=5001(fedora),501(centos),505(distro),506(peguin)
[root@little ~]#
[root@little ~]# groupadd -rg 808 mydisk
[root@little ~]#
[root@little ~]# tail -1 /etc/group
mydisk:x:808:
[root@little ~]#
[root@little ~]# useradd iscsi -u 808 -g mydisk -rM
[root@little ~]#
[root@little ~]# tail -1 /etc/passwd
iscsi:x:808:808::/home/iscsi:/bin/bash
[root@little ~]#
[root@little ~]# tail -1 /etc/group
mydisk:x:808:
[root@little ~]#
[root@little ~]# id iscsi
uid=808(iscsi) gid=808(mydisk) groups=808(mydisk)
[root@little ~]#
linux-practice(1-19)