JASMIN Storage migration

We are pleased to announce that new storage hardware is now in place to replace older capacity on JASMIN, so a major storage migration is about to start.

In summary:

• New storage purchased for JASMIN last year is now in place but will replace rather than expand storage capacity
• A major activity will now begin to move all (400+) group workspaces (GWSs) from old to new storage
• However, most GWS volume sizes will need to be “squeezed” by around a third in order to make space for new projects
• GWS managers will be asked to prioritise those data which need to remain online (on disk), which can move to near-line storage, and which can be removed.
• Each GWS will be given a window of dates in the next few months when their migration will need to happen
• Once the task for GWS data has been completed, we then need to move the entire CEDA Archive too!

We will shortly begin liaising with individual GWS managers about the details and timing of each migration, aiming to draw up a calendar of migration dates which minimises disruption, over the coming year. The JASMIN team will assist with moving the “online” data.

As an individual user, you can help prepare for this now by:

• Considering (individually and with your project colleagues) which data actually need to remain on disk
  • From our own analyses, a large proportion of data within GWSs has not been accessed, let alone modified, for significant periods of time.
• Replacing “hard-wired” absolute paths to data with relative paths or environment variables. The path (e.g. /gws/nopw/j04/mygws) to each GWS will change when the GWS is moved, so the old path will no longer work.

Reminder: GWS storage on JASMIN is a finite resource provided to projects on a temporary basis for the active phase of a project only, after which it needs to be reclaimed so that it can be re-used by other projects. Projects needing to store data for longer, or to serve as inputs for other projects, should speak to the CEDA Archive team about a data management plan, ideally at the project planning stage.

Storing data, particularly on disk, has high hardware and energy costs - both financial and environmental, so we need you to help us make JASMIN as efficient as it can be so that we can continue to support your needs as a community as new science projects need to use JASMIN, within the finite resources available.

Thanks in advance for your cooperation.

JASMIN Team