Skip to content

Frequently Asked Questions#

Access#

Can I Access Elm from Sherlock and/or SCG?#

Yes. Although Elm is not mounted on Sherlock or SCG directly, you can use the S3 API to access Elm using many of the same tools you'd use to interact with common cloud vendor storage like rclone, aws-cli, and s5cmd. All these systems managed by Stanford Research Computing, including Elm, are connected to the Stanford Research Network at 100Gb/s. See our Elm User Guide page for more information.

How does Elm handle access control and file sharing?#

Stanford Workgroup Manager is used to provide you with three Stanford Workgroups which allow you manage varying levels of access to your bucket. These are automatically created for you based on your bucket name and risk classification. Workgroups define who can read, write, or upload data to the bucket. For example, a bucket called examplebucket in Moderate-Risk will generate:

  • elm:p-campus_examplebucket

    • Read-only membership: Members can view objects but cannot create or modify them.

  • elm:p-campus_examplebucket_uploader

    • Read and limited write membership: Members can view and upload objects, but cannot delete them.

  • elm:p-campus_examplebucket_editor

    • Full read-write membership: Members can view, upload, and delete objects.

Note

High-Risk buckets prepend elm-hr: instead of elm: and use campus.elm-hr.stanford.edu for the URL.
The bucket’s workgroups become elm-hr:p-campus_<bucket>, etc.

Workgroup administrators can add or remove people in these workgroups via Stanford Workgroup Manager, ensuring your team has the correct level of access.

Moving Data#

Can I access Elm from my desktop/laptop?#

Yes, please see the Elm User Guide page.

Can I mount Elm on my own computer at Stanford?#

Yes. Tools like rclone, allow yout to mount S3 storage targets like Elm.

Backup#

Is Elm backed up?#

No, Elm is not backed up. While Elm has redundancy features like erasure coding, it’s still located on campus. This means Elm should be considered a single copy of your data. If there’s a big disaster (think earthquakes), there’s a chance you might lose access. For extra-important data, it’s a good idea to keep a second copy on another system.

Quotas#

How are Elm quotas measured?#

Elm quotas are measured in allocations of 1 TiB. Your quota is a hard limit that you set before you upload data to Elm. This ensures you never get a surprise storage bill and unlike cloud competetors, ongoing costs can be predictably managed and forecasted.

Directory#

Can I create a directory in S3?#

There is no concept of a directory in S3, just object keys and key prefixes. An S3 key may have a '/' character in it that serves as a useful analog to a directory path: https://docs.aws.amazon.com/AmazonS3/latest/userguide/using-prefixes.html

Under the hood, MinIO is backed by a real filesystem so it is in fact capable of creating empty directories, but there's no guarantee empty directories will be visible at the S3 layer: https://blog.min.io/prefix-vs-folder/

News & Alerts#

How can I stay up-to-date on Elm?#

We highly recommend that all Elm users join the SRCC Slack workspace (SUNet ID Required) and follow the #elm-announce channel to stay abreast of system updates, maintenance, or outages. #elm-users is best for sharing best practices and asking questions among a welcoming community of other Elm users.

Email notification for system maintenance and issues#

Elm administrators maintain a mailing list called Elm-announce. This very low-traffic list is used for official announcements such as planned maintenance. Elm users are automatically subscribed to this list by default. For more information, please see the following page:

Elm-announce List Information