CentOS permission system recovery/restoration

CentOS permission system recovery/restoration

Sometimes the chmod-R is 777/, and the system is paralyzed ~ What should we do ?? Let's take a look.

First, you must prepare the same system as the faulty machine. For example, you can install a linux

Create a waynerQiu. c program in the new system. The content is as follows:

1234567891011121314151617 #include <sys/stat.h> #include <ftw.h> int list( const char *name, const struct stat *status, int type) { if (type == FTW_NS) return 0; printf ( "%s 0%3o\n" , name, status->st_mode & 07777); return 0; } int main( int argc, char *argv[]) { if (argc == 1) ftw( "." , list, 1); else ftw(argv[1], list, 2); exit (0); }

Compile the file and export the permission information.

1234 # Compile gcc waynerQiu.c -o waynerQiu.com # Permission to execute and export related directories . /waynerQiu .com / >> waynerQiu.txt

Copy the exported file to the faulty machine and execute the following script.

123456789101112131415 #!/bin/sh if [ $ # != 1 ] then echo Usage : $0 \<filename\> exit fi PERMFILE=$1 cat $PERMFILE | while read LINE do FILE=` echo $LINE | awk '{print $1}' ` PERM=` echo $LINE | awk '{print $2}' ` chmod $PERM $FILE #echo "chmod $PERM $FILE" done echo "change perm finished! "

You can save the script as a shell file, such as mygod. sh.

Then execute

1 mygod.sh waynerQiu.txt

After the program runs, restart the system to see if it has been restored?