Upload files to Backblaze B2 with SFTP or FTPS or SCP?

Backblaze B2 Cloud Storage is totally compatible with the Amazon S3 API.

The Backblaze Help article Can WinSCP with B2? recommends the following for using the free tool WinSCP.

WinSCP can be configured with B2 Cloud Storage by following the steps below.

1. Start WinSCP and you are automatically taken to the connection manager page.

2. Click on New Site and then under File Protocol, select Amazon S3. Enter the S3 Endpoint URL, Key ID, and Application Key (App Keys) into the appropriate fields.

If you're writing a bash script, you could use the B2 command-line tool. For example:

export B2_APPLICATION_KEY_ID=<Your App Key ID>
export B2_APPLICATION_KEY=<Your App Key>

b2 upload-file <Your-Bucket-Name> </path/to/file> <filenameInB2>