Storage

Permanent storage per testbed

When a node is swapped in in your experiment, an NFS share will be mounted, which is accessible by all people in your subauthority/project.

This NFS share is mounted as:

/groups/wall2-ilabt-iminds-be/[projectname]/

(if you have a certificate from another authority than the Virtual Wall, the 2nd part will be different)

The nice thing is that:

  • the share is mounted automatically on all your nodes
  • the share is permanent, so after your experiment is done, the data will remain there
  • the share is shared with all people in your project

Note that this storage is only available per testbed, so it is not shared accross the testbeds.

Local storage per node

To speed up the deployment of nodes on the testbed, the initial image that is deployed only occupies a small partition off a bigger disk. When you plan on creating a new image of your node later on, you should avoid enlarging this partition too much, as this will slow down the imaging process (both creation and later deployment).

However, if you are not planning on imaging your server for later use, you can safely enlarge the partition to occupy the full disk. Another option is to use this free space on the disk to create a separate partition for your local storage needs.

Enlarging your root partition to the full disk size

Warning

Try this only on a fresh node, not if you already have activated an extra partition. Since you are manpulating partition and filesystems, it is always possible to LOSE DATA! You have been warned! The script referenced here does some sanity checks, which should make it quite safe.

You can use the script https://www.wall2.ilabt.iminds.be/expand-root-disk.sh to automatically expand the root partition so it occupies the entire disk.

To quickly execute the script on a node, run:

sudo bash -e -c '. <(wget -O - -q https://www.wall2.ilabt.iminds.be/expand-root-disk.sh)'

Note

NOTE: It is recommended to reboot the node after modifying the partition, to make sure everything is still working OK.

You can examine the script to see how this works. The basics steps are:

  • First, find the root disk, and check if it contains 4 partitions as expected on the virtual wall: The 1st partition is the root, the 2nd and 4th are empty, and the 3rd is a swap.
  • Delete partition 2, 3 and 4, and expand partition 1 to fill the entire disk, using a tool like fdisk. (The script uses sfdisk, which is better suited for use in scripts.)
  • Expand the filesystem on the root partition so it uses the entire extended partition.

Extra disk space on seperate partition

There is still free space on the root disk, that you can partition yourself with fdisk. You can for example modify partition 4, put a filesystem on it, and them mount it where you need extra diskspace.

Alternativly, the pcgen1 nodes on Virtual Wall 1 have 3 extra disks (/dev/sdb, /dev/sdc, /dev/sdd) which work nicely in a RAID0 configuration.

See Hardware for information on disk capacity per node.