Zend Cache Error – Silverstripe 2.4 admin

After uploading a new site built on Silverstripe 2.4 to my shared host, the following error reared it’s head when trying to access the admin area.

[User Error] Uncaught Zend_Cache_Exception: cache_dir is not writable

After some searching through the Silvstripe forums, I finally ended up at finding a resolved support ticket that showed an easy solution in the mysite/_config.php.

First, check the silverstripe-cache folder exists in your site’s root directory, and ensure it is writable.

Then add the following line anywhere in your _config.php file.

$_SERVER['TMPDIR'] = '/absolute_path_to_your_cache_foler/silverstripe-cache';

Finally revisit your admin with flushed cache (/admin?flush=1)

This fix worked fine for me but I have seen it hasn’t worked for others. A last case solution for those that need a quick fix would be to edit the cache directory in /sapphire/thirdparty/Zend/Cache/Backend/File.php.  Change:

protected $_options = array(
'cache_dir' => 'CHANGE_TO_CACHE_DIR',
'file_locking' => true,
'read_control' => true,
'read_control_type' => 'crc32',
'hashed_directory_level' => 0,
'hashed_directory_umask' => 0700,
'file_name_prefix' => 'zend_cache',
'cache_file_umask' => 0600,
'metadatas_array_max_size' => 100
);

The file is part of the Sapphire core so this solution is not advised as a long term fix, and could quick easily be overwritten in future updates.