s3cmd : Configure multiple s3 buckets of multiple aws accounts on same server

First configure s3 bucket of 'AWS account - A' with s3cmd

s3cmd --configure

Add Access key and Secret Key of your 'AWS account A'.

Now rename ~/.s3cfg to ~/.s3cfg-first

You can find .s3cfg file in your home directory of logged in user.

Now configure s3 bucket of 'AWS account - B'

s3cmd --configure

Add Access key and Secret Key of your 'AWS account B'.

Now rename ~/.s3cfg to ~/.s3cfg-second
 
Configure third and so on

If you do not define config file parameter in command, it takes default config file i.e. .s3cfg

You need to define config file with command and you can communicate with different s3 buckets of one AWS account or multiple AWS accounts.

s3cmd ls s3://bucketname -c ~/.s3cfg-first

Above command will list the content of the defined s3 bucket of AWS account - A.

s3cmd ls s3://bucketname -c ~/.s3cfg-second

Similarly it will list the content of the defined s3 bucket of AWS account - B.

Now you can copy content, delete content or move them with different s3cmd commands.

Note : Number of buckets you can access of AWS account A or AWS account B, it depends on the privileges provided to access key and secret key and privileges are defined by the policy attached to the user whose access key and secret key you are using. 

If a policy which has read, write and list access of only one bucket 'Bucket-A' of an AWS account and this is the only policy attached to a user whose access key and secret key you are using then you can access only Bucket-A of that AWS account by using the access key and secret key of the user.