AFS Basic Usage

Basic Usage

When you login to a CSAIL Linux machine or have AFS installed and setup correctly on Windows or Mac, you obtain a “token” that verifies your identity to the file system. This token has a lifetime of 10 hours. If your token expires you lose access to your AFS directories.

To check if you have a token, type:

tokens

To obtain a new token, type:

aklog

To create your Kerberos ticket, type:

kinit

If you remain logged-in to a computer for over 10 hours you may find that the computer won’t let you write to your own files. This is because your token has expired, or you may have lost network connection or been timed out. Run

kinit && aklog

(or, equivalently, our convenience script renew, which is probably in your $PATH).

Long-running jobs

By default, Kerberos tickets and AFS tokens expire automatically to protect your account. For automated tasks, long-running compute jobs, or persistent terminal sessions, you will need to use specific tools to prevent your Kerberos tickets from expiring. See the Guide to Long-Running and Uninterrupted Sessions for officially supported methods and important security policies.

AFS quotas

By default, most volumes are set initially at 20G. If you, your group, or project requires more personal storage than this, please contact help@csail.mit.edu

To list your volume quota, type:

fs listquota