Whenever a new FreeBSD version supports new features for ZFS, an upgrade of the existing pools is necessary. This is indicated when the status of a pool is displayed:
# zpool status zroot pool: zroot state: ONLINE status: Some supported features are not enabled on the pool. The pool can still be used, but some features are unavailable. action: Enable all features using 'zpool upgrade'. Once this is done, the pool may no longer be accessible by software that does not support the features.
When I first set up my server, I got numerous daily attempts to login via SSH almost immediately. None of them were successful, because I use public key authentication, of course, but the log spam was annoying nonetheless. The problem is with only 232 addresses, scanning all possible IPv4 addresses for open ports is quite easy.
But, yet again, IPv6 to the rescue. It has 2128 possible addresses, so scanning all of them for open ports is doable but takes a significant amount of time.
While there are many fancy backup tools, often a simple daily rsync may already be sufficient. The advantage of an rsync backup is that it’s file system based, so no special tools are required to browse and access the files in the backup. However, rsync only copies the files, so there is no security measure like encryption. That’s fine locally or within a private network, but sometimes you only have a backup space you can’t trust, like a share on another machine or cloud storage.
My home server runs FreeBSD 11.0, and, of course, has full disk encryption. This requires a passphrase to be entered while booting, so I need a keyboard and monitor attached, and have to be in the same room for restarts and after power outages. This is not acceptable at all. There is no need for a display and keyboard otherwise, and I want to be able to enter the passphrase remotely, but without compromising security.
FreeBSD runs great on a Raspberry Pi, but the official images are all stable or current branches and there is no support for binary updates, i.e. freebsd-update. So I tried to figure out how to install the latest release version and keep it updated as well, without starting from scratch with a new image every time.
While it is possible to build a kernel and world on the Raspberry Pi itself, it takes about a week to finish (trust me, I tried) and you need a much larger /tmp on a disk or share for it to work in the first place.