Scratch Space

isginf operates a storage server for temporary data that does not need backup. Each research group can have their own shares with dedicated storage for their users.

Each group that uses this service usually has a share scratch that is available to all users of the group.

Optional Dedicated Disks and Disk-to-disk Backup

Research groups with large data needs can buy large quantities of storage buy buying disks. Disks are added to the system in groups of eight at once (RAID6 with 6 disks and two parity). With 18TB drives the usable space would then be ~100TB.

We also offer to do daily disk-to-disk backup to a secondary storage server. Research groups just have to buy twice the amount of disks, two groups of eight disks.

ITCs can contact our service desk if they are interested.

Disk-to-disk Backup for Large Systems

For backup of large servers such as GPU servers with large NVMEs for fast local data, we also offer only to buy disks for the backup service. Such systems cannot be registered with the tape backup service.

The only requirement is that the data to be backed up on the system reside on ZFS and that the systems to be backed up are managed by ISG. We only back up one mount point (usually /local) per server.

Availability and Safety of Data

The system needs to be booted from time to time to upgrade the operating system. This is typically announced to the ITCs beforehand.

We use server-grade hardware but there is no redundancy on the level of the server. The storage uses RAID 6 on groups of eight disks to make it resilient even to multiple hard drive failures. Snapshots of the file systems protect against accidental deletion.

Backup

Access

Access to the shares can be through NFS4 with Kerberos, NFS3 on demand or SMB/CIFS. The available shares for each group are typically worked out with the groups ITC.

The list of shares of your group on the scratch space along with the access policies can be found in the section with information for research groups.

Integration in isginf Linux Installations

On Linux installations managed by isginf the shares are accessible under /pub (via autofs), i.e., the scratch share is available under /pub/scratch.