通过PHP进行SSH备份问题

Question

I am trying to backup all the files on our server using some SSH commands via PHP and I have a script working to some extent.

The problem is that only some of the folders actually contain any files but the folder structure seems to be correct though.

This is the script I am using:

<?php
   $output = `cd /
   ls -al
   tar -cf /home/b/a/backup/web/public_html/archive.tar home/*`;

   echo "<pre>$output</pre>";
?>

I cant even view the files via SSH commands, an example of this is the test account. If I use the following command I am unable to view the website files.

<?php
   $output = `cd /home/t/e/test/
   ls -alRh`;

   echo "<pre>$output</pre>";
?>

But if I use the same commands on the a different account I am able to see and download of the website files.

Is this a permission problem or am I missing something in my script?

Thanks

Answer 1

I think it permission problem, try to give apache user(or what you set it) permission to read /home/* directory's. To find the user name that used by apache service run this: For linux:

egrep -iw --color=auto 'user|group' /etc/httpd/conf/httpd.conf

For FreeBSD:

egrep -iw --color=auto '^user|^group' /usr/local/etc/apache22/httpd.conf

Answer 2

My guess is that PHP is running in a chroot.

If you just want to execute a backup, consider doing it in a different language. Especially if it is just a sequence of UNIX commands, write a shell script. Perhaps more details on what this script will be used for and who is providing and maintaining your hosting will be useful.

Answer 3

ls -l / | grep home

the output will be like this:

lrwxr-xr-x   1 root  wheel        8 Mar 30 14:13 home -> usr/home

In my case, the owner is root , and the root user its primary group is wheel , so now we add www-data user to wheel group so he can list files in there:

usermod -a -G wheel www-data

You can download some files because they located in directory owned by www-data user, and when you can't, www-data has no permission in that.