System O & M skills (I) -- chattr and lsattr commands

System O & M skills (1) -- chattr and lsattr commands we have the requirement that a file cannot be modified, deleted, or added only, so we can use the chattr command. [Plain] [root @ serv01 test] # cat note.txt 1. don't be late 2. do not leave early 3. do not smoke [root @ serv01 test] # chattr + I note.txt # root users cannot edit [root @ serv01 test] # vim note.txt [root @ serv01 test] # cat note.txt 1. don't be late 2. do not leave early 3. do not smoke # root users cannot delete and modify [root @ serv01 test] # rm-f note.txt rm: cannot remove 'note.txt ': operation not permitted [root @ serv01 test] # echo "this is test"> note.txt-bash: note.txt: Permission denied # ll view the file owner Can not be seen, you need to use lsattr to view [root @ serv01 test] # ll note.txt-rw-r --. 1 root 45 Sep 21 note.txt [root @ serv01 test] # lsattr note.txt ---- I -------- e-note.txt # It's only a relative concept that root users cannot modify, root users can modify file attributes, you can modify [root @ serv01 test] # chattr-I note.txt [root @ serv01 test] # lsattr note.txt ------------- e-note.txt [root @ serv01 test] # vim note.txt [root @ serv01 test] # cat note.txt 1. don't be late 2. do not leave early 3. do not smoke 4. don't come to work # Message Board: You cannot delete [root @ serv01 test] # vim note.txt [root @ serv01 test] # cat note.txt 1. don't be late 2. do not leave early 3. do not smoke 4. hello [root @ serv01 test] # chattr + a note.txt [root @ serv01 test] # lsattr note.txt ----- a ------- e-note.txt [root @ serv01 test] # vim note.txt [root @ serv01 test] # ls note.txt ~ Note. txy ~ Note. txz ~ # Delete the file and find that you do not have the permission [root @ serv01 test] # rm-rf * rm: remove regular file 'note.txt '? Y rm: cannot remove 'note.txt ': Operation not permitted [root @ serv01 test] # ls note.txt upload [root @ serv01 test] # echo "hello world"> note.txt-bash: note.txt: operation not permitted # Only content can be appended [root @ serv01 test] # echo "hello world"> note.txt [root @ serv01 test] # cat note.txt 1. don't be late 2. do not leave early 3. do not smoke 4. hello world [root @ serv01 test] # chattr-a note.txt [root @ serv01 test] # lsattr note.txt ------------- e-note.txt