$ setfacl -m u:user1 rw file

To remove all extended ACL entries

$ setfacl -b file.txt

To remove entries from the ACL of file, To remove group 'ilugc' from a file's ACL

$ setfacl -x g:ilugc file.txt

To remove the default ACL

$ setfacl -k file

To apply operations to all files and directories recursively 

$ setfacl -m g:ilugc:rw -R directory

To restore a permission backup

$ setfacl --restore=file

To copy the ACL of one file to another

$ getfacl example.txt | setfacl --set-file=- f sample.txt

regards,

T.Dhanasekar