Working with large files
In order to allow transfers of big files, SabreDAV makes use of streams everywhere internally.
This allows you to deal with very large files (tried up to 15GB), without requiring a high number for memory_limit.
For this to work, output buffering must be turned off. It appears to be on for some php installations. Not turning this off will make PHP return memory-related errors.
In php ini, this should be:
Or if you're setting php settings through apache:
php_flag output_buffering off
More information can be found on webservers.
32bit vs 64bit
The maximum filesize we can currently represent on 32bit systems is 2 GB. To support files larger than 2GB, make sure that your PHP is compiled for 64 bit.
We recently found out that PHP's
fpassthru() method is broken
for large files, and does not allow files to be served over 2GB.
A fix has been made for SabreDAV 1.7.11 and 1.8.9. So make sure you are running at least one of those two versions.
If you're running Apache, and particularly on a shared host, there's a
reasonable chance mod_security is deployed, which can limit the total
size of request bodies and thus restricts large uploads with
The main symptomn for this is a server responding with the HTTP status code
413 Request Entity Too Large.
The setting to look for is called