dotfiles/nix/system/svalbard/README.md

## ZFS
To set up ZFS on the spinning discs, followed steps derived from these sources (but without encryption):
* https://ipetkov.dev/blog/installing-nixos-and-zfs-on-my-desktop/
* https://cheat.readthedocs.io/en/latest/nixos/zfs_install.html

```sh
# zpool status
# DISK=<disk from /dev/disk/by-id>
# POOL=<a name for the pool>
# zpool create "${POOL}" $DISK
# zfs create -o compression=on -o mountpoint=legacy "${POOL}/main"
```

then added the ZFS filesystem to `hardware-configuration.nix` (use the zfs
created label as the device) and rebooted.

### Adding a new disk to the pool

Based on https://unix.stackexchange.com/questions/530968/adding-disks-to-zfs-pool, it should be straightforward
as long as what you're trying to do is simply extend a pool's storage by adding a new vdev:

```sh
# fdisk -l
# ls -l /dev/disk/by-id
# DISK=<the new disk, based on which one is pointed to the right /dev/sdX>
# fdisk $DISK
# zpool status
# zpool add <pool> $DISK
```

Since we've chosen single-disks for the storage pool, it's going to be annoying
if we ever decide to go for any redundancy like raidz. We'll have to buy quite
a few disks and copy over all the data :sob:. That is a good prompt to cull
un-valued data!

Someday, it might be possible to grow a raidz vdev by adding disks, instead of
by replacing disks: https://github.com/openzfs/zfs/pull/12225

## NFS

Don't forget to `chown` the mounted system so that non-root can read/write there.


If your NFS clients are able to mount the store but can't `ls` it or see any
conents, make sure that the store is still, in fact, readable to non-owners!!!