그룹

https://opentutorials.org/course/2598/14298

 

 

앞의 d 는 디렉토리를 의미

rwx rwx rwx 

1     2     3

1번은 해당 디렉토리나 파일을 만든 당사자.

2번은 그룹의 권한

3번은 일반모두의 권한

 

 

 

john과 smith를 dev라는 그룹으로 묶고 그들만 접근가능한 testdev 디렉토리를 만들어보자.

 

/var에 testdev 디렉토리 생성.

/var# mkdir testdev
/var# cd testdev
/var/testdev# echo 'hello rainy day' > rain.txt
/var/testdev# ll
total 12
drwxr-xr-x  2 root root 4096 Jun 25 13:19 ./
drwxr-xr-x 14 root root 4096 Jun 25 13:19 ../
-rw-r--r--  1 root root   16 Jun 25 13:19 rain.txt
/var/testdev# groupadd dev
/var/testdev# vi /etc/group
...
...
...
mysql:x:123:
test:x:1001:
smith:x:1003:
dev:x:1004:

/var/testdev# usermod -a -G dev john
/var/testdev# usermod -a -G dev smith
/var/testdev# exit
logout

========================================

/var# cd /var/testdev
/var/testdev# ll
total 12
drwxr-xr-x  2 root root 4096 Jun 25 13:19 ./
drwxr-xr-x 14 root root 4096 Jun 25 13:19 ../
-rw-r--r--  1 root root   16 Jun 25 13:19 rain.txt
/var/testdev# chown root:dev .
/var/testdev# ll
total 12
drwxr-xr-x  2 root dev  4096 Jun 25 13:19 ./
drwxr-xr-x 14 root root 4096 Jun 25 13:19 ../
-rw-r--r--  1 root root   16 Jun 25 13:19 rain.txt
/var/testdev# chmod 771 .
/var/testdev# ll
total 12
drwxrwx--x  2 root dev  4096 Jun 25 13:19 ./
drwxr-xr-x 14 root root 4096 Jun 25 13:19 ../
-rw-r--r--  1 root root   16 Jun 25 13:19 rain.txt

 

 

--x

chmod 751 .
/var/testdev# ll
total 12
drwxr-x--x  2 root dev  4096 Jun 25 13:19 ./
drwxr-xr-x 14 root root 4096 Jun 25 13:19 ../
-rw-r--r--  1 root root   16 Jun 25 13:19 rain.txt

cd /var/testdev
/var/testdev$ ll
ls: cannot open directory '.': Permission denied

디렉토리에 들어가는것은 가능. 단 리스트 보기가 불가.

 

r--

chmod 754 .
/var/testdev# ll
total 12
drwxr-xr--  2 root dev  4096 Jun 25 13:19 ./
drwxr-xr-x 14 root root 4096 Jun 25 13:19 ../
-rw-r--r--  1 root root   16 Jun 25 13:19 rain.txt
cd /var/testdev
-bash: cd: /var/testdev: Permission denied
ll /var/testdev
ls: cannot access '/var/testdev/.': Permission denied
ls: cannot access '/var/testdev/..': Permission denied
ls: cannot access '/var/testdev/rain.txt': Permission denied
total 0
d????????? ? ? ? ?            ? ./
d????????? ? ? ? ?            ? ../
-????????? ? ? ? ?            ? rain.txt

 

디랙토리에 들어가는것은 불가능. 단 리스트보기는 가능.