Having just run into this issue - for me the fix was disabling SELinux and rebooting the server.
Putting:
SELINUX=disabled
in
/etc/sysconfig/selinux
Resolved the issue of that error.
hth
Fred
Answered just a couple of days ago here https://moodle.org/mod/forum/discuss.php?d=165833#p1462303
While the info in the link does show how ... if one is un-sure ... suggest setting SELinux to 'permissive' rather than 'disabled'. That will show SELinux 'complaints' in web server logs ... ie, what it wanted to block ... so that you can then 'fix' those. Once you see no SELinux 'complaints', turn SELinux to enforcing.
'spirit of sharing', Ken
Disabling SELinux does reduce security, so working out how to fix the issues is definately useful - thanks for posting the link to: https://moodle.org/mod/forum/discuss.php?d=165833#p1462303