maybe it’s a good way to start here
Upload limits are more or less not nextcloud but php and OS concerned.
php.upload-max-filesize
php.post-max-size
php.max-input-time
php.max-execution-time
The default maximum file size for uploads is 512MB. You can increase this limit up to what your filesystem and operating system allows. There are certain hard limits that cannot be exceeded:
- < 2GB on 32Bit OS-architecture
- < 2GB with IE6 - IE8
- < 4GB with IE9 - IE11
64-bit filesystems have much higher limits; consult the documentation for your filesystem.
Another aspect is that it can be helpful to additionally set a new chunk size to nextcloud when operating with very large files.
For this see the admin manual here:
https://docs.nextcloud.com/server/latest/admin_manual/configuration_files/big_file_upload_configuration.html#adjust-chunk-size-on-nextcloud-side
And third the browser itself also can be a limiter.
e.g. upload with M$ Edge fails → but with Firefox / Chrome works.
So feel free to check this as well when having the correct php options set.