NFS Export Policy for global file-systems to Nirin

Overview

The NCI Global Filesystems (commonly known as gdata) can be accessed from the Nirin cloud by way of NFS gateways, which mount the gdata filesystems and provide NFS exports which are accessible from the cloud. Projects with gdata resource allocations can request access via the helpdesk.

Please note that NCI requires written approval by a project CI before NFS access to that project's gdata directories can be granted, and when any changes are made to the export.

NFS exports can be either read-only (the preferred approach whenever possible) or read-write. In either case all access to the underlying gdata filesystem will be squashed to a single user

Requesting Access

gdata NFS export requests should be made via the NCI helpdesk. Requests should indicate what project the request relates to, what kind of access is required, and who the approving CI is. The CI should provide their written approval in a comment in the ticket.

The ticket will be processed in two steps: firstly, the cloud team will configure the project network to support gdata NFS access; once that is done the ticket will be forwarded to the storage team to create the actual NFS exports, and the ticket will be resolved. Once the ticket is resolved the NFS export should be accessible.

Mounting NFS Exports

Once the exports are in place, mounting the exported filesystem can be done using a command like the following:

Here the project is ab12, and the export is from the the gdata4 filesystem. The general form is:

In order to configure an instance so that the NFS exports are mounted automatically you can add a line for each mount to the /etc/fstab file:

Mounting an NFS share requires a mount.nfs helper program, which may need to be installed manually; e.g. on Ubuntu systems: sudo apt install nfs-common

Note:  mount options can also be specified, both on the command line and in the fstab  entry, however they are generally unnecessary - the NFS client and server will negotiate options during the mount process, and generally the result will be the optimal set of options. Tuning mount options is possible, but without some care this can lead to performance degradation.

Appendices

A. NFS Servers

Note: Unless specifically instructed only the round-robin name should be used for mounting an NFS export.