PHP fopen() fails on files even with wide-open permissions

Question

I\'m currently migrating my LAMP from my Windows Server to a VPS running Debian 6. Most everything is working, however, one of the PHP scripts was failing to write to its c

Answer 1

Remember that in order to reach a file, ALL parent directories must be readable by www-data. You strace output seems to indicate that even accessing /var/log/apache2/writetest is failing. Make sure that www-data has permissions on the following directories:

• / (r-x)
• /var (r-x)
• /var/log (r-x)
• /var/log/apache2 (r-x)
• /var/log/apache2/writetest (rwx)
• /var/log/apache2/writetest/writetest.log (rw-)

Answer 2

Could be a SELinux issue, even if Debian doesn't ship it in the default installation your provider could have enabled it. Look for messages in /var/log with

grep -i selinux /var/log/{syslog,messages}

If that's the cause and you need to disable it, here are instructions: look for file /etc/selinux/config, here it's default content. Change SELINUX directive to disabled and reboot the system.

# This file controls the state of SELinux on the system.
# SELINUX= can take one of these three values:
#   enforcing - SELinux security policy is enforced.
#   permissive - SELinux prints warnings instead of enforcing.
#   disabled - SELinux is fully disabled.
SELINUX=disabled
# SELINUXTYPE= type of policy in use. Possible values are:
#   targeted - Only targeted network daemons are protected.
#   strict - Full SELinux protection.
SELINUXTYPE=targeted

Answer 3

Does the php file doing the writing have proper permissions set? Try changing those to see if that's the issue.