Miriad Data Disks at Epping

As datasets are normal directories, they can be created wherever you can create directories. Though it is possible to create them in your home directory, given the quotas enforced on home directories you are unlikely to be able to store much data there.

Epping users can use the /DATA disks (shared with AIPS users) to store their data for a few days to a few weeks. To do so, you should create a directory /DATA/host_x/username, where host_x is a machine name and a number (e.g. ATLAS_1) and username is your login name. For example

     % mkdir /DATA/ATLAS_1/rsault

creates a directory for rsault on the first data disk of machine atlas.

All the disks attached to all the different workstations are accessible from any machine. That is, the disks are cross-mounted between the computers. However there is a right way and a wrong way to use this cross-mounting - there is a large network penalty (particularly to write) to a remote disk. For example, there is a large overhead if you write to a disk attached to APUS when you are logged into CARINA. The penalty is smaller if you read from a network mounted disk, but is still substantial. In general you should attempt to keep your data on the disks of one workstation, and use that workstation for all your compute and I/O intensive work.

There are two sorts of disks - public and bookable. Public disks can be used by anyone at anytime. However their contents may be automatically cleared at 5:00 am on Mondays. The bookable disks provide a private allocation of disk space, which is not subject to destruction on Monday morning. Note, however, when your booking has expired, your data can be deleted from a bookable disk without warning. Disks can be booked by e-mailing `bookings'.