try -d opcache.log_verbosity_level=3, it probably because /tmp/.opcache is not accessable

Changed the log_verbosity_level to 3 with the following result:

Thu Jan  7 10:11:34 2016 (26904): Warning opcache.file_cache must be a full path of accessable directory.
Thu Jan  7 10:11:34 2016 (26904): Fatal Error opcache.file_cache_only is set without a proper setting of opcache.file_cache

Information of the directory:

ls -al /tmp/.opcache/
totaal 8
drwxrwxrwx   2 root root 4096  5 jan 23:36 .
drwxrwxrwt. 15 root root 4096  7 jan 10:11 ..

So directory has all the rights to be used.
Checked the PHP code https://github.com/php/php-src/blob/master/ext/opcache/ZendAccelerator.c :


#ifdef HAVE_OPCACHE_FILE_CACHE
	} else if (!ZCG(accel_directives).file_cache) {
		accel_startup_ok = 0;
		zend_accel_error(ACCEL_LOG_FATAL, "opcache.file_cache_only is set without a proper setting of opcache.file_cache");
		return SUCCESS;
	} 

So this error will only be shown if opcache.file_cache is empty right? Which is not the case.

Was able to get it working by changing the path to:

opcache.file_cache=/home/admin/public_html/.opcache

Why is it not working with /tmp/.opcache while this folder is set in the open_basedir setting:
open_basedir	/home/admin/:/tmp:/var/tmp:/usr/local/lib/php/:/usr/local/php70/lib/php/

Changed the owner of /tmp/.opcache to admin which is the same as /home/admin/public_html/.opcache but still it doesn't work in the /tmp directory.

Same problem on Windows. PHP 7.0.14/7.1.0

display_errors = On
display_startup_errors = On
error_reporting = E_ALL
extension_dir = ".\ext"
zend_extension=php_opcache.dll
opcache.enable = 1
opcache.enable_cli = 1
opcache.huge_code_pages = 1
opcache.file_cache = ".\temp\opcache"
opcache.file_cache_only = 1
opcache.file_cache_consistency_checks = 1
opcache.file_cache_fallback = 1

php --version
=> (13140): Fatal Error opcache.file_cache_only is set without a proper setting of opcache.file_cache

I've experienced the same issue and found out that you cannot set absolute path for opcache directory, only relative, for reasons unknown. I.e.
/var/www/html/.opcache doesn't work
../html/.opcache does

I know it's an old question, but:
>> Why is it not working with /tmp/.opcache while this folder is set in the open_basedir setting:
>> open_basedir	>> /home/admin/:/tmp:/var/tmp:/usr/local/lib/php/:/usr/local/php70/lib/php/

I think debian uses a virtual /tmp/ directory for each process. so if you create .opcache within you ssh's /tmp/ that directory does not exists in apache's /tmp dir.
try simply using /tmp/ then it should work

in 2018 each service should have it's own /tmp and /var/tmp for obvious security reasons and so /tmp is pretty fine

https://www.freedesktop.org/software/systemd/man/systemd.exec.html

PrivateTmp=
Takes a boolean argument. If true, sets up a new file system namespace for the executed processes and mounts private /tmp and /var/tmp directories inside it that is not shared by processes outside of the namespace. This is useful to secure access to temporary files of the process, but makes sharing between processes via /tmp or /var/tmp impossible. If this is enabled, all temporary files created by a service in these directories will be removed after the service is stopped. Defaults to false. It is possible to run two or more units within the same private /tmp and /var/tmp namespace by using the JoinsNamespaceOf= directive, see systemd.unit(5) for details. This setting is implied if DynamicUser= is set. For this setting the same restrictions regarding mount propagation and privileges apply as for ReadOnlyPaths= and related calls, see above. Enabling this setting has the side effect of adding Requires= and After= dependencies on all mount units necessary to access /tmp and /var/tmp. Moreover an implicitly After= ordering on systemd-tmpfiles-setup.service(8) is added.

> I think debian uses a virtual /tmp/ directory for each process.
> so if you create .opcache within you ssh's /tmp/ that directory
> does not exists in apache's /tmp dir.

Good catch!

> try simply using /tmp/ then it should work

Does it?

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