Learn Linux CCNA CEH IPv6 Cyber-Security Online

In this tutorial we will learn how to configure advance permissions using ACL(Access Control List).

In this article we will learn following:

1.How to check the ACL on files or folders using getfacl command.
2.How to identify files/directories that have ACL.
3.How to set ACL on specif files or Folders.
4.How to create the same ACL on all newly created files automatically.
5.How to remove particular ACL entry.
6.How to remove all ACL entries from a file or folder.

Before starting this lab  we will create some users some groups and some files and folders in linux to test acl command and show it with examples.

First of all i am going to create a folder /data

[root@localhost ~]# mkdir /data

 

Now i am gong to create user tiwary and assigned it password.

[root@localhost ~]# useradd tiwary

[root@localhost ~]# passwd tiwary

 

Then create a group named linux.

[root@localhost ~]# groupadd linux

 

Then we will check whether acl package is installed in our linux machine or not using below command.
[root@localhost ~]# rpm -q acl

  acl-2.2.39-3.el5

Hence you can see acl package is already installed.
If in your linux machine acl package is not available you can install it using yum.

[root@localhost ~]# yum install acl

 

How to set ACL for user tiwary on /data directory.

[root@localhost ~]# setfacl -m u:tiwary:rw /data

How to set ACL for group linux on /data folder.

 

[root@localhost ~]# setfacl -m g:linux:rwx /data

 

How to Check the ACL entries on /data Folder now?

[root@localhost ~]# getfacl /data

 

How to create the same ACL on all newly created files automatically.

[root@localhost ~]# setfacl -Rm g:linux:rwx /data

How to Set the same acl’s on all newly created files automatically.

[root@localhost ~]# setfacl -dm g:linux:r /tmp

How to Set all users to have read, write and execute to /data directory.

[root@localhost ~]# setfacl -m o::rwx /data

How to remove ACL entry for user tiwary on /data directory.

below command will remove only specified ACL from file/directory.
[root@localhost ~]# setfacl -x u:tiwary /data

How to remove all the acl’s on /data Directory

below command will remove all ACL from file/direcoty.

[root@localhost ~]# setfacl -b /data

 

ACL advance tutorial with some more example labs will come soon in my next article in ACL part-2.

If you have any doubt or suggestions you can suggest here through comments.