S3Express FAQ and Knowledge Base

Backing up your files to Amazon S3 using S3Express command line utility is very simple!

1. The first step is to enter your Amazon S3 credentials in S3Express using the command saveauth. This needs to be done only once: S3Express will then remember your credentials each time.
    
2. Next you execute the put command. This will upload all files, or just selected files, in any local or network directory you specify, to a bucket in your Amazon S3 account. Files can be selected based on folder, extension, size, age, etc. You can memorize the command you execute in a shortcut, so next time the command can be issued in no time.
    
3. The first time the put command is executed, S3Express will upload all files that are not already present on Amazon S3. However the next time, you can instruct S3Express to only upload files that have changed since last upload and new files. This will make the backup very fast!
    
4. The upload operation can be stopped and restarted at any time. It will run silently in the background and report at the end if there were any errors. If stopped, it will the restart from where it left. 
      
5. There's many options that can be used to optimize your backup to S3: you can use encryption (local or server-side based), you can limit the Bandwidth used by S3Express, so the backup will not interfere with other programs that need to use the network, you can instruct S3Express to automatically retry a file upload after X seconds and X times in case of a network error, you can use multiple threads to achieve maximum speed, you can use Amazon S3 multipart uploads to upload large files, you can keep the existing metadata and/or ACL when overwriting files, and even simulate the upload before actually starting the upload.
     
6. And once S3Express has finished uploading all files, you can be reassured that all your files are securely and reliably backed up to Amazon S3. Amazon S3 guarantees up to 99.999999999% durability, with 99.99% availability!
     

The following is an example of put commands used to upload / backup files to S3:

put  c:\myfolder\  mybucketname  -s -onlydiff  -e

This uploads only changed or new files from c:\folder\ to <mybucketname> and encrypts the files as they arrive to Amazon S3 (option -e). Changed files are files whose content that changed since last backup, while new files are files that are not yet present in the Amazon S3 bucket. Options -s instructs S3Express to also upload files that are in subfolders of c:\myfolder\. -onlynew (upload only new files), -onlynewer (upload only files that have a newer timestamp) and -onlyexisting (re-upload only files that are already present on S3) are also available.

More details in the PDF tutorial 'Backup Files to Amazon S3 with S3Express'.