study notes 2<\/p>\n
— command line file<\/p>\n
1, create and delete files<\/p>\n
Create a file touch xxxx<\/p>\n
touch -t 20151225 create a file and specify time properties<\/p>\n
rm xxx delete the file<\/p>\n
rm -rf forced to delete files<\/p>\n
2. Create a directory and delete the directory<\/p>\n
mkdir -p xxx\/yyy recursively create directories;<\/p>\n
rmdir xxx delete empty directories;<\/p>\n
rm -rf XXX forcibly remove non-empty directories;<\/p>\n
3, copy files and directories<\/p>\n
cp \/path1\/xxx \/path2\/xxx\/<\/p>\n
cp -p \/path1\/xxx \/path2\/yyy copy files to retain the original file attributes;<\/p>\n
cp -Rf (or -rf)\/path1\/ \/path2\/ copy files to a directory directory path1 path2<\/p>\n
cp -a cp -dR –preserve=all<\/p>\n
4 Cut files<\/p>\n
mv \/path1\/xx \/path2\/yy<\/p>\n
5 View Files<\/p>\n
cat xx less
\nmore
\nless<\/p>\n
3– redirection and piping<\/p>\n
Redirect correct content:<\/p>\n
cat xx.file> yy.file equivalent<\/p>\n
cat xx.file 1> yy.file redirected to the file contents yy.file, will overwrite the original file contents;<\/p>\n
cat \/etc\/passwd & >> \/tmp\/xx<\/p>\n
cat \/etc\/passwd > \/tmp\/xx 2>&1<\/p>\n
tail -f \/var\/log\/messages >\/tmp\/xx 2>\/tmp\/yy<\/p>\n
ps aux | grep tail | grep -v ‘grep’<\/p>\n
ls -al \/dev\/<\/p>\n
to redirect the file contents input to a command<\/p>\n
tr<\/p>\n
cat > \/tmp\/xxx <<EOF
\n>test1
\n>test2
\n>test3
\n>EOF<\/p>\n
cat <<EOF> \/tmp\/xxx
\n>test2
\n>test3
\n>test4
\n>EOF<\/p>\n
number of rows grep -n before looking for the number of rows plus -i ignore case, -A 3 looking for then displayed, B 3 show the number of rows -v looking for negative keywords before after content, -q Do not display output;<\/p>\n
grep -n1 B1 -A root \/etc\/passwd<\/p>\n
ifconfig | grep ‘inet’|grep -v ‘inet6’| awk ‘BEGIN{print “IP\\t\\tnetmask”}{print $2,”\\t”,$4}END{}’<\/p>\n
ifconfig | grep ‘inet’|grep -v ‘inet6’| tee -a \/tmp\/yy|awk ‘BEGIN{print “IP\\t\\tnetmask”}{print $2,”\\t”,$4}END{}’<\/p>\n
4 – Vim editor use<\/p>\n
1, gedit graphical editing files<\/p>\n
2, Vim operating a file, if the file exists is opened, if the file does not exist, it is created:<\/p>\n
When using Vim to edit the file to open, the default is the command-line mode:<\/p>\n
4. When you edit the file, enter the command line insert mode, press the following keys to enter:<\/p>\n
i, from the current cursor enters;<\/p>\n
a, from the current cursor one character to enter;<\/p>\n
o, in the current row into the next row;<\/p>\n
I, from the current cursor jump to the beginning of the line and into the Bank;<\/p>\n
A, skip to the end and enter the Bank;<\/p>\n
O, in the Bank of the line to insert a row;<\/p>\n
r, to replace the current character;<\/p>\n
R, to replace the current character and move to the next character;<\/p>\n
number + G: jump to a specific row, such as 10G jumps to line 10, GG jump to the last line, gg jump to the first line;<\/p>\n
number + yy: copy current number of rows down, in any line can be pasted by p;<\/p>\n
number + dd: Cut down the number of rows currently in any line adhesive according to p;<\/p>\n
u: undo the last step of the operation;<\/p>\n
ctrl + r: to restore the previous step;<\/p>\n
ctrl + v: to enter visual block mode, the cursor moves up and down, select the content, press y copy selected content, at any position by pasting;<\/p>\n
Fast beginning of the line to add a comment #, move the cursor to select the line, then press I to the start position,<\/p>\n
press #, press ESC to exit<\/p>\n
#abrt:x:173:173::\/etc\/abrt:\/sbin\/nologin
\n#pulse:x:171:171:PulseAudio System Daemon:\/var\/run\/pulse:\/sbin\/nologin
\n#gdm:x:42:42::\/var\/lib\/gdm:\/sbin\/nologin
\n#gnome-initial-setup:x:993:991::\/run\/gnome-initial-setup\/:\/sbin\/nologin
\n:split?ctrl+w<\/p>\n
To view detailed help Vim, you can enter Vimtutor.<\/p>\n
5, line mode to save the file, find, property settings, replacement and other operations<\/p>\n
Enter the last line mode, ESC from insert into command mode, enter \ud83d\ude41 \/ or generally used to find, n from the look down, N from the look-up)<\/p>\n
Save: wq to save and exit, or x;<\/p>\n
Force Quit: q without saving the file content;!<\/p>\n
Display line numbers: set nu, if the default display line numbers, you will need to modify the home directory vimrc file or \/ etc \/ vimrc, no file is created, insert a row set nu;<\/p>\n
Switching specified line: direct input line number;<\/p>\n
Replace: 1,$s \/old \/new \/g Replace globally all<\/p>\n
m, ns \/old \/new \/g replace m row to match the contents of all n rows, on behalf of the current line, $representatives last line,
\n$ -. 1 represents the penultimate line, (1, $) can also be used to replace%,
\nThey are expressed full text. If you want to match the contents of which have special characters such as \/, *, etc., to be added in front of the escape character \\<\/p>\n
You can use the s # old # new #, using the # separator, the special characters do not need to escape;<\/p>\n
Find backslash below, if you want to ignore the case, look at the back of the content plus \\ c, for example: \/ servername \\ c<\/p>\n
study notes 5– manage users and user groups<\/p>\n
[root@RHEL7HARDEN \/]# passwd –help
\nUsage: passwd [OPTION…] <accountName>
\n-k, –keep-tokens keep non-expired authentication tokens
\n-d, –delete delete the password for the named account (root only)
\n-l, –lock lock the password for the named account (root only)
\n-u, –unlock unlock the password for the named account (root only)
\n-e, –expire expire the password for the named account (root only)
\n-f, –force force operation
\n-x, –maximum=DAYS maximum password lifetime (root only)
\n-n, –minimum=DAYS minimum password lifetime (root only)
\n-w, –warning=DAYS number of days warning users receives before password expiration (root only)
\n-i, –inactive=DAYS number of days after password expiration when an account becomes disabled (root only)
\n-S, –status report password status on the named account (root only)
\n–stdin read new tokens from stdin (root only)<\/p>\n
Help options:
\n-?, –help Show this help message
\n–usage Display brief usage message
\n[root@RHEL7HARDEN \/]#<\/p>\n
[root@RHEL7HARDEN \/]# chage –help
\nUsage: chage [options] LOGIN<\/p>\n
Options:
\n-d, –lastday LAST_DAY set date of last password change to LAST_DAY
\n-E, –expiredate EXPIRE_DATE set account expiration date to EXPIRE_DATE
\n-h, –help display this help message and exit
\n-I, –inactive INACTIVE set password inactive after expiration
\nto INACTIVE
\n-l, –list show account aging information
\n-m, –mindays MIN_DAYS set minimum number of days before password
\nchange to MIN_DAYS
\n-M, –maxdays MAX_DAYS set maximim number of days before password
\nchange to MAX_DAYS
\n-R, –root CHROOT_DIR directory to chroot into
\n-W, –warndays WARN_DAYS set expiration warning days to WARN_DAYS<\/p>\n
root@RHEL7HARDEN \/]# useradd –help
\nUsage: useradd [options] LOGIN
\nuseradd -D
\nuseradd -D [options]<\/p>\n
Options:
\n-b, –base-dir BASE_DIR base directory for the home directory of the
\nnew account
\n-c, –comment COMMENT GECOS field of the new account
\n-d, –home-dir HOME_DIR home directory of the new account
\n-D, –defaults print or change default useradd configuration
\n-e, –expiredate EXPIRE_DATE expiration date of the new account
\n-f, –inactive INACTIVE password inactivity period of the new account
\n-g, –gid GROUP name or ID of the primary group of the new
\naccount
\n-G, –groups GROUPS list of supplementary groups of the new
\naccount
\n-h, –help display this help message and exit
\n-k, –skel SKEL_DIR use this alternative skeleton directory
\n-K, –key KEY=VALUE override \/etc\/login.defs defaults
\n-l, –no-log-init do not add the user to the lastlog and
\nfaillog databases
\n-m, –create-home create the user’s home directory
\n-M, –no-create-home do not create the user’s home directory
\n-N, –no-user-group do not create a group with the same name as
\nthe user
\n-o, –non-unique allow to create users with duplicate
\n(non-unique) UID
\n-p, –password PASSWORD encrypted password of the new account
\n-r, –system create a system account
\n-R, –root CHROOT_DIR directory to chroot into
\n-s, –shell SHELL login shell of the new account
\n-u, –uid UID user ID of the new account
\n-U, –user-group create a group with the same name as the user
\n-Z, –selinux-user SEUSER use a specific SEUSER for the SELinux user mapping<\/p>\n
[root@RHEL7HARDEN \/]# usermod –help
\nUsage: usermod [options] LOGIN<\/p>\n
Options:
\n-c, –comment COMMENT new value of the GECOS field
\n-d, –home HOME_DIR new home directory for the user account
\n-e, –expiredate EXPIRE_DATE set account expiration date to EXPIRE_DATE
\n-f, –inactive INACTIVE set password inactive after expiration
\nto INACTIVE
\n-g, –gid GROUP force use GROUP as new primary group
\n-G, –groups GROUPS new list of supplementary GROUPS
\n-a, –append append the user to the supplemental GROUPS
\nmentioned by the -G option without removing
\nhim\/her from other groups
\n-h, –help display this help message and exit
\n-l, –login NEW_LOGIN new value of the login name
\n-L, –lock lock the user account
\n-m, –move-home move contents of the home directory to the
\nnew location (use only with -d)
\n-o, –non-unique allow using duplicate (non-unique) UID
\n-p, –password PASSWORD use encrypted password for the new password
\n-R, –root CHROOT_DIR directory to chroot into
\n-s, –shell SHELL new login shell for the user account
\n-u, –uid UID new UID for the user account
\n-U, –unlock unlock the user account
\n-Z, –selinux-user SEUSER new SELinux user mapping for the user account<\/p>\n
[root@RHEL7HARDEN \/]# useradd test1
\n[root@RHEL7HARDEN \/]# mkdir \/home\/test
\nroot@RHEL7HARDEN \/]# usermod -d \/home\/test1 test
\nusermod: user ‘test’ does not exist
\n[root@RHEL7HARDEN \/]# cp -a \/etc\/skel\/.[^.]* \/home\/test\/
\n[root@RHEL7HARDEN \/]# groups test1
\ntest1 : test1
\nusermod -a -G mohan test1<\/p>\n
usermod -g<\/p>\n
[root@RHEL7HARDEN \/]# gpasswd –help
\nUsage: gpasswd [option] GROUP<\/p>\n
Options:
\n-a, –add USER add USER to GROUP
\n-d, –delete USER remove USER from GROUP
\n-h, –help display this help message and exit
\n-Q, –root CHROOT_DIR directory to chroot into
\n-r, –delete-password remove the GROUP’s password
\n-R, –restrict restrict access to GROUP to its members
\n-M, –members USER,… set the list of members of GROUP
\n-A, –administrators ADMIN,…
\nset the list of administrators for GROUP
\nExcept for the -A and -M options, the options cannot be combined.<\/p>\n","protected":false},"excerpt":{"rendered":"
study notes 2<\/p>\n
— command line file<\/p>\n
1, create and delete files<\/p>\n
Create a file touch xxxx<\/p>\n
touch -t 20151225 create a file and specify time properties<\/p>\n
rm xxx delete the file<\/p>\n
rm -rf forced to delete files<\/p>\n
2. Create a directory and delete the directory<\/p>\n
mkdir -p xxx\/yyy recursively create directories;<\/p>\n
rmdir xxx delete […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[73],"tags":[],"_links":{"self":[{"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/posts\/7293"}],"collection":[{"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mohan.sg\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=7293"}],"version-history":[{"count":1,"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/posts\/7293\/revisions"}],"predecessor-version":[{"id":7294,"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/posts\/7293\/revisions\/7294"}],"wp:attachment":[{"href":"https:\/\/mohan.sg\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=7293"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mohan.sg\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=7293"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mohan.sg\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=7293"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}