Multipart backup archives. Some backup archives may consist of more than one files. These are called multipart backup archives. You MUST download all part files to have a backup archive set which can be used to extract all files and restore a site. All files have the same base name, for example site-www.example.com-20220925-105300-abcdef012345, but different extensions. JPA archives have the extensions .jpa, .j01, .j02, …; JPS archives have the extensions .jps, .j01, .j02, …; ZIP archives have the extensions .zip, .z01, .z02, … The part files of a multipart backup archive are NOT separate archives; you cannot extract its one of them individually. The are all parts of the same archive and they all need to be present for the archive to be able to be extracted. The order of the parts is .j01, .j02, …, .jpa for JPA archives; .j01, .j02, …, .jps for JPS archives; and .z01, .z02, …, .zip for ZIP archives. That is to say, the numbered part files come first in the numeric order defined by their extension, the file with the .jpa, .jps or .zip extension comes last. You can extract multipart archives using the integrated restoration but also Akeeba Kickstart Core, our free of charge archive extraction tool. It can run on a web server — even a local web server created with MAMP, WAMPserver, XAMPP etc — or, for expert users, on the command line.
https://www.akeeba.com/documentation/akeeba-backup-joomla/restoring-backups.html#general-guidelines
Please remember that you need to upload all files: .jpa, .j01, .j02 etc. The first file of the split backup archive is .j01, followed by .j02 etc and the last file is the .jpa file.
When uploading the files make sure to use either SFTP (file transfer over the SSH protocol). If you are using FTP instead you have to tell your FTP client to use the Binary transfer mode (not ASCII/Text, not Auto).
If you still have a problem, please let me know exactly what happens when the restoration fails. I need to know if it's a problem with the extraction, the database restoration, something else… The more I know about where it fails, the more I can infer about how it fails and how to help you.
Nicholas K. Dionysopoulos
Lead Developer and Director
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