custom_cached_disks_base_directory
This setting specifies the cache path for custom (created from SQL) cached disks.custom_cached_disks_base_directory has higher priority for custom disks over filesystem_caches_path (found in filesystem_caches_path.xml),
which is used if the former one is absent.
The filesystem cache setting path must lie inside that directory,
otherwise an exception will be thrown preventing the disk from being created.
This will not affect disks created on an older version for which the server was upgraded.
In this case, an exception will not be thrown, to allow the server to successfully start.