- 1 year ago
php is_writable returns always false for a writable mount
If the PHP function is_writable()
consistently returns false
for a writable mount, there are a few potential causes and troubleshooting steps you can follow:
Check permissions: Ensure that the user running the PHP script has the necessary permissions to write to the mount point. Verify both the user and group permissions for the directory. You can use the
ls -l
command to check the ownership and permissions of the mount point.Confirm file system type: Check if the file system type of the mount point is compatible with the permissions you are trying to set. Some file systems, such as FAT32, may not support fine-grained permissions like Unix file systems do. In such cases, you may need to handle permissions differently.
Verify file ownership: Ensure that the owner of the PHP script and the mount point are the same. If the PHP script is executed by a different user than the owner of the mount point, it may not have the necessary permissions to write to the mount. Check the ownership using the
ls -l
command.Check SELinux or AppArmor settings: If you are using SELinux or AppArmor on your system, they may be preventing PHP from writing to the mount point. Check the security policies and rules for the specific mount point and make necessary adjustments to allow write access.
Test with a simple PHP script: Create a simple PHP script that attempts to write to the mount point directly using functions like
file_put_contents()
orfopen()
. Run this script and check if it successfully writes to the mount point. If it does, it suggests an issue with theis_writable()
function specifically.Disable open_basedir restriction: If the
open_basedir
directive is enabled in your PHP configuration, it may restrict PHP from accessing certain directories, including the mount point. Temporarily disableopen_basedir
to see if it resolves the issue. However, exercise caution as this can introduce security risks if not properly managed.Check for filesystem errors: Run a file system check (e.g.,
fsck
) on the mount point to ensure there are no file system errors or corruption that might be causing the issue.
By following these troubleshooting steps, you should be able to identify and resolve the issue with is_writable()
returning false
for a writable mount in PHP.