Change ONLYOFFICE Workspace’s Default Storage Location
Move portal data from Disk Default to a supported cloud storage provider, or relocate Docker data safely by changing its host volume mapping.
You use HJSplit to split and join files , but when using the Start button, you get the "I / O error 123" error message. And how to overcome?
Most of the time when using HJSplit, the error is due to improper use of the user, so this situation occurs. So please refer to the following article to understand the causes and find solutions to continue the process of file splitting:

I / O error message error 123
Please rename the folder or existing files inside that folder with unsigned characters. Because HJSplit does not support other languages, naming it will cause the above error.

Rename the same pair of files, only the component behind.
For example: As shown in the picture below, there are 7 files separated from the complete file, then named as: Hai-Hoai-Linh.MP4.001, Hai-Hoai-Linh.MP4.002 until Hai-Hoai-Linh. MP4.007 so that when pairing does not occur I / O error 123.
This error is very easy to fix, but many people have got in trouble and struggling to find a solution. Hopefully the above article will help you use HJSplit more effectively.
In addition, you can refer to the following software: MKVToolnix , Alon Video Joiner , Zealot Video Workshop ... to split and join Video easily and quickly.
I wish you successful implementation!
Move portal data from Disk Default to a supported cloud storage provider, or relocate Docker data safely by changing its host volume mapping.
Identify whether Document Server uses a Linux package or Docker, remove only its components, and check remaining data without deleting shared services by mistake.
Trace slow collaborative editing to Docker resource pressure, proxy connections, or document load, then choose the fix that matches your measurements.
Install custom fonts in ONLYOFFICE Document Server, compare persistent Docker mounts with direct copies, rebuild the font list, and verify the result.
Choose where TLS should terminate, mount a trusted certificate and private key safely, and verify HTTPS access to a Dockerized ONLYOFFICE Docs server.
Embed the ONLYOFFICE editor in your PHP app, sign its configuration with JWT, and save edited files through a secure callback.
Set the proofing language for the whole document or selected text, confirm spell checking is active, and identify when a server dictionary is missing.
Enable persistent Track Changes for everyone in one ONLYOFFICE document, verify edits are recorded, and understand the limits of this setting.
Find whether Nginx, Docker networking, or an internal ONLYOFFICE service is returning 502, then verify the corrected upstream and health check.
Diagnose failed ONLYOFFICE saves by checking the Nextcloud callback route, proxy redirects, and storage logs, then verify the edited file persists.