S3cmd Command Line Tool

S3cmd is a free command-line tool that enables you to upload and download data to S3 object storage. Written in Python, S3cmd is an open-source project licensed under the GNU Public License v2 (GPLv2), making it free for both personal and commercial use.

⚠️

We recommend using the AWS CLI whenever possible, as we encountered some issues with S3cmd. For example, bucket names cannot start with numbers or uppercase letters.

Installing the S3cmd Tool

S3cmd is available in the system repositories for CentOS, RHEL, and Ubuntu. You can install it using the following guide.

On CentOS/RHEL

sudo yum install s3cmd

On Ubuntu/Debian

sudo apt install s3cmd

Configuring the S3cmd Tool

Add the following lines to the configuration file located at /home/user/.s3cfg.

[default]
    host_base = https://s3.clX.du.cesnet.cz
    use_https = True
    access_key = xxxxxxxxxxxxxxxxxxxxxx
    secret_key = xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
    host_bucket = s3.clX.du.cesnet.cz

the host_base and host_bucket refer to the S3 endpoint URL, which you received via email along with your access_key and secret_key. This information is sent to you during the S3 account creation process.

Configuration file with GPG encryption

[default]
host_base = https://s3.clX.du.cesnet.cz
    use_https = True
    access_key = xxxxxxxxxxxxxxxxxxxxxx
    secret_key = xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
    host_bucket = s3.clX.du.cesnet.cz
    gpg_command = /usr/bin/gpg
    gpg_decrypt = %(gpg_command)s -d --verbose --no-use-agent --batch --yes --passphrase-fd %(passphrase_fd)s -o %(output_file)s %(input_file)s
    gpg_encrypt = %(gpg_command)s -c --verbose --no-use-agent --batch --yes --passphrase-fd %(passphrase_fd)s -o %(output_file)s %(input_file)s
    gpg_passphrase = xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

Basic S3cmd Commands

S3cmd commands support basic bucket operations - creation, listing, and deletion.

Bucket operations

Bucket name
The bucket name must be unique within the tenant and can only contain lowercase letters, uppercase letters, numbers, dashes, and dots. It must start with a letter or number and cannot have dots next to dashes or multiple consecutive dots.

Listing all s3 buckets

s3cmd ls

Creation of a new s3 bucket

s3cmd mb s3://newbucket

Removing an s3 bucket

s3cmd rb s3://newbucket

Only emptied bucket can be removed!

Listing an s3 bucket size

s3cmd s3://newbucket/ du

File and directory operations

Listing of an s3 bucket

s3cmd ls s3://newbucket/

File upload

s3cmd put file.txt s3://newbucket/

Upload of encrypted files

s3cmd put -e file.txt s3://newbucket/

Directory upload

s3cmd put -r directory s3://newbucket/

Please ensure that you haven’t forgotten to remove the trailing slash (e.g. .: directory/). The trailing slash indicates that only the contents of the specified directory will be uploaded.

Downloading file from an s3 bucket

s3cmd get s3://newbucket/file.txt

Data deletion from an s3 bucket

s3cmd del s3://newbucket/file.txt

s3cmd del s3://newbucket/directory

Data sync to an s3 bucket from a local machine

s3cmd sync /local/path/ s3://newbucket/backup/

Data sync from an s3 bucket to a local machine

3cmd sync s3://newbucket/backup/ ~/restore/