Syncthing on Unraid: repairing malformed database disk image

Mostly as a note to myself, but here’s what to do if you’re running linuxserver/syncthing via Docker on Unraid and it keeps saying:

ERR Database error when getting previous version (error="getkv: database disk image is malformed (11)" log.pkg=syncthing)

The problem is that Syncthing’s index has been corrupted. I was able to fix it by getting a shell into the relevant Docker container and moving the index: Syncthing detected it as absent and re-created it, re-indexing everything. Here’s what I did:

docker exec -it syncthing bash
mv /config/index-v2 /config/index-v2-BROKEN

Everything fixed itself immediately and the Docker logs showed the reindex underway.

5 Cool Apps for your Unraid NAS

I’ve got a (now four-year-old) Unraid NAS called Fox and I’m a huge fan. I particularly love the fact that Unraid can work not only as a NAS, but also as a fully-fledged Docker appliance, enabling me to easily install and maintain all manner of applications.

A cube-shaped black computer sits next to a battery pack on a laminated floor. A sign has been left atop it, reading "Caution: Generator connected to this installation."
There isn’t really a generator attached to Fox, just a UPS battery backup. The sign was liberated from our shonky home electrical system.

I was chatting this week to a colleague who was considering getting a similar setup, and he seemed to be taking notes of things he might like to install, once he’s got one. So I figured I’d round up five of my favourite things to install on an Unraid NAS that:

  1. Don’t require any third-party accounts (low dependencies),
  2. Don’t need any kind of high-powered hardware (low specs), and
  3. Provide value with very little set up (low learning curve).
Dan, his finger to his lips and his laptop on his knees, makes a "shush" action. A coworker can be seen working behind him.
It’d have been cooler if I’d have secretly written this blog post while sitting alongside said colleague (shh!). But sadly it had to wait until I was home.

Here we go:

Syncthing

I’ve been raving about Syncthing for years. If I had an “everyday carry” list of applications, it’d be high on that list.

Syncthing screenshot for computer Rebel, sharing with Fox, Idiophone, Lemmy and Maxine.
Syncthing’s just an awesome piece of set-and-forget software that facilitates file synchronisation between all of your devices and can also form part of a backup strategy.

Here’s the skinny: you install Syncthing on several devices, then give each the identification key of another to pair them. Now you can add folders on each and “share” them with the others, and the two are kept in-sync. There’s lots of options for power users, but just as a starting point you can use this to:

  • Manage the photos on your phone and push copies to your desktop whenever you’re home (like your favourite cloud photo sync service, but selfhosted).
  • Keep your Obsidian notes in-sync between all your devices (normally costs $4/month).1
  • Get a copy of the documents from all your devices onto your NAS, for backup purposes (note that sync’ing alone, even with versioning enabled, is not a good backup: the idea is that you run an actual backup from your NAS!).

Huginn

You know IFTTT? Zapier? Services that help you to “automate” things based on inputs and outputs. Huginn’s like that, but selfhosted. Also: more-powerful.

Screenshot showing Huginn workflows.
When we first started looking for a dog to adopt (y’know, before we got this derper), I set up Huginn watchers to monitor the websites of several rescue centres, filter them by some of our criteria, and push the results to us in real-time on Slack, giving us an edge over other prospective puppy-parents.

The learning curve is steeper than anything else on this list, and I almost didn’t include it for that reason alone. But once you’ve learned your way around its idiosyncrasies and dipped your toe into the more-advanced Javascript-powered magic it can do, you really begin to unlock its potential.

It couples well with Home Assistant, if that’s your jam. But even without it, you can find yourself automating things you never expected to.

FreshRSS

I’ve written a lot about how and why FreshRSS continues to be my favourite RSS reader. But you know what’s even better than an awesome RSS reader? An awesome selfhosted RSS reader!

FreshRSS screenshot.
Yes, I know I have a lot of “unread” items. That’s fine, and I can tell you why.

Many of these suggested apps benefit well from you exposing them to the open Web rather than just running them on your LAN, and an RSS reader is probably the best example (you want to read your news feeds when you’re out and about, right?). What you need for that is a reverse proxy, and there are lots of guides to doing it super-easily, even if you’re not on a static IP address.2. Alternatively you can just VPN in to your home: your router might be able to arrange this, or else Unraid can do it for you!

Open Trashmail

You know how sometimes you need to give somebody your email address but you don’t actually want to. Like: sure, I’d like you to email me a verification code for this download, but I don’t trust you not to spam me later! What you need is a disposable email address.3

Open Trashmail screenshot showing a subscription to Thanks for subscribing to Dan Q's Spam-Of-The-Hour List!
How do you feel about having infinite email addresses that you can make up on-demand (without even having access to a computer), subscribe to by RSS, and never have to see unless you specifically want to.

You just need to install Open Trashmail, point the MX records of a few domain names or subdomains (you’ve got some spare domain names lying around, right? if not; they’re pretty cheap…) at it, and it will now accept email to any address on those domains. You can make up addresses off the top of your head, even away from an Internet connection when using a paper-based form, and they work. You can check them later if you want to… or ignore them forever.

Couple it with an RSS reader, or Huginn, or Slack, and you can get a notification or take some action when an email arrives!

  • Need to give that escape room your email address to get a copy of your “team photo”? Give them a throwaway, pick up the picture when you get home, and then forget you ever gave it to them.
  • Company give you a freebie on your birthday if you sign up their mailing list? Sign up 366 times with them and write a Huginn workflow that puts “today’s” promo code into your Obsidian notetaking app (Sync’d over Syncthing) but filters out everything else.
  • Suspect some organisation is selling your email address on to third parties? Give them a unique email address that you only give to them and catch them in a honeypot.

YOURLS

Finally: a URL shortener. The Internet’s got lots of them, but they’re all at the mercy of somebody else (potentially somebody in a country that might not be very-friendly with yours…).

YOURLS screenshot (Your Own URL Shortener).
It isn’t pretty, but… it doesn’t need to be! Nobody actually sees the admin interface except you anyway.

Plus, it’s just kinda cool to be able to brand your shortlinks with your own name, right? If you follow only one link from this post, let it be to watch this video that helps explain why this is important: danq.link/url-shortener-highlights.

I run many, many other Docker containers and virtual machines on my NAS. These five aren’t even the “top five” that I use… they’re just five that are great starters because they’re easy and pack a lot of joy into their learning curve.

And if your NAS can’t do all the above… consider Unraid for your next NAS!

Footnotes

1 I wrote the beginnings of this post on my phone while in the Channel Tunnel and then carried on using my desktop computer once I was home. Sync is magic.

2 I can’t share or recommend one reverse proxy guide in particular because I set my own up because I can configure Nginx in my sleep, but I did a quick search and found several that all look good so I imagine you can do the same. You don’t have to do it on day one, though!

3 Obviously there are lots of approachable to on-demand disposable email addresses, including the venerable “plus sign in a GMail address” trick, but Open Trashmail is just… better for many cases.

× × × × × × ×

My Default Apps at the End of 2023

Kev Quirk, Colin Walker, and other cool kids I follow online made it sound fun to share your “lifestack” as we approach the end of 2023.

So here’s mine: my digital “everyday carry” list of the tools and services I routinely use:

  • 📨 Mail Service: Proton Mail
  • 📮 Mail Client: Thunderbird (Desktop), Proton Mail App (Android), Proton Mail webmail (anywhere else)
  • 📝 Notes: Obsidian, Syncthing (for cross-device sync)
  • To-Do: Obsidian, physical notepad [not happy with this; want something more productive]
  • 📆 Calendar: Google Calendar (via Thunderbird on Desktop) [not happy with this; want something not-Google – still waiting on Proton Calendar getting good!]
  • 🙍🏻‍♂️ Contacts: Proton Mail
  • 📖 RSS Service: FreshRSS, selfhosted
  • 🗞️ RSS Client: FreshRSS (Desktop), FeedMe (Android)
  • ⌨️ Launcher: RayCast (MacOS), PowerToys Run (Windows)
  • ☁️ Cloud storage: ownCloud (selfhosted)
  • 🌅 Photo library: plain old directories! [would like: something selfhosted, mostly filesystem-driven, with Web interface]
  • 🌐 Web Browser: Firefox (everywhere)
  • 💬 Chat: Slack, WhatsApp, Signal, Telegram
  • 🔖 Bookmarks: Firefox (easy access), Wallabag (selfhosted, for long-term archiving)
  • 📚 Reading: dead tree format [my Kindle v2 died and I’m seeking a non-Amazon replacement; suggestions welcome], Calibre
  • 📜 Word Processing: Microsoft Word, Google Docs
  • 📈 Spreadsheets: Microsoft Excel, Google Sheets
  • 📊 Presentations: reveal.js
  • 🛒 Shopping Lists: pen and paper
  • 💰 Personal Finance: Google Sheets
  • 🎵 Music: YouTube Music [not entirely happy with it; considering replacement]
  • 🎤 Podcasts: FreshRSS; experimenting with Pocket Casts
  • 🔐 Password Management: KeePassXC, Syncthing (for cross-device sync)
  • 🤦‍♂️ Social Media: Mastodon, selfhosted
  • 🔎 Search: DuckDuckGo
  • 🧮 Code Editor: Sublime Text
  • ⌨️ KVM: Barrier
  • 🗺️ Navigation: OpenStreetMap, Google Maps, Talkietoaster (Garmin Montana)
  • 📍 Location Tracking: uLogger
  • 🔗 Blog: WordPress, selfhosted

Keeping 2FA Secrets in a Password Safe?

The two most important things you can do to protect your online accounts remain to (a) use a different password, ideally a randomly-generated one, for every service, and (b) enable two-factor authentication (2FA) where it’s available.

If you’re not already doing that, go do that. A password manager like 1Password, Bitwarden, or LastPass will help (although be aware that the latter’s had some security issues lately, as I’ve mentioned).

Diagram showing a password safe on a desktop computer being used to fill the username and password parts of a login form, and a mobile phone providing the information for the second factor.
For many people, authentication looks like this: put in a username and password from a password safe (or their brain), and a second factor from their phone.

I promised back in 2018 to talk about what this kind of authentication usually1 looks like for me, because my approach is a little different:

Diagram showing a password safe on a desktop computer being used to fill the username, password, AND second factor parts of the form.
My password manager fills the username, password, and second factor parts of most login forms for me. It feels pretty magical.

I simply press my magic key combination, (re-)authenticate with my password safe if necessary, and then it does the rest. Including, thanks to some light scripting/hackery, many authentication flows that span multiple pages and even ones that ask for randomly-selected characters from a secret word or similar2.

Animated GIF showing a login form requesting a username, password, and "Google Authenticator Code". An auto-typer fills all three fields with the username "2fa-autotype-demo", a long password, and the code 676032. The "Remember Me" checkbox is left unticked.
I love having long passwords and 2FA enabled. But I also love being able to log in with the convenience of a master password and my fingerprint.

My approach isn’t without its controversies. The argument against it broadly comes down to this:

Storing the username, password, and the means to provide an authentication code in the same place means that you’re no-longer providing a second factor. It’s no longer e.g. “something you have” and “something you know”, but just “something you have”. Therefore, this is equivalent to using only a username and password and not enabling 2FA at all.

I disagree with this argument. I provide two counter-arguments:

1. For most people, they’re already simplifying down to “something you have” by running the authenticator software on the same device, protected in the same way, as their password safe: it’s their mobile phone! If your phone can be snatched while-unlocked, or if your password safe and authenticator are protected by the same biometrics3, an attacker with access to your mobile phone already has everything.

Repeat of the diagram in which a PC provides all authentication, except the PC has been replaced with a phone.
If your argument about whether it counts as multifactor is based on how many devices are involved, this common pattern also isn’t multifactor.

2. Even if we do accept that this is fewer factors, it doesn’t completely undermine the value of time-based second factor codes4. Time-based codes have an important role in protecting you from authentication replay!

For instance: if you use a device for which the Internet connection is insecure, or where there’s a keylogger installed, or where somebody’s shoulder-surfing and can see what you type… the most they can get is your username, password, and a code that will stop working in 30 seconds5. That’s still a huge improvement on basic username/password-based system.6

Note that I wouldn’t use this approach if I were using a cloud-based password safe like those I linked in the first paragraph! For me personally: storing usernames, passwords, and 2FA authentication keys together on somebody else’s hardware feels like too much of a risk.

But my password manager of choice is KeePassXC/KeePassDX, to which I migrated after I realised that the plugins I was using in vanilla KeePass were provided as standard functionality in those forks. I keep the master copy of my password database encrypted on a pendrive that attaches to my wallet, and I use Syncthing to push secondary copies to a couple of other bits of hardware I control, such as my phone. Cloud-based password safes have their place and they’re extremely accessible to people new to password managers or who need organisational “sharing” features, but they’re not the right tool for me.

As always: do your own risk assessment and decide what’s right for you. But from my experience I can say this: seamless, secure logins feel magical, and don’t have to require an unacceptable security trade-off.

Footnotes

1 Not all authentication looks like this, for me, because some kinds of 2FA can’t be provided by my password safe. Some service providers “push” verification checks to an app, for example. Others use proprietary TOTP-based second factor systems (I’m looking at you, banks!). And some, of course, insist on proven-to-be-terrible solutions like email and SMS-based 2FA.

2 Note: asking for a username, password, and something that’s basically another-password is not true multifactor authentication (I’m looking at you again, banks!), but it’s still potentially useful for organisations that need to authenticate you by multiple media (e.g. online and by telephone), because it can be used to help restrict access to secrets by staff members. Important, but not the same thing: you should still demand 2FA.

3 Biometric security uses your body, not your mind, and so is still usable even if you’re asleep, dead, uncooperative, or if an attacker simply removes and retains the body part that is to be scanned. Eww.

4 TOTP is a very popular mechanism: you’ve probably used it. You get a QR code to scan  into the authenticator app on your device (or multiple devices, for redundancy), and it comes up with a different 6-digit code every 30 seconds or so.

5 Strictly, a TOTP code is likely to work for a few minutes, on account of servers allowing for drift between your clock and theirs. But it’s still a short window.

6 It doesn’t protect you if an attacker manages to aquire a dump of the usernames, inadequately-hashed passwords, and 2FA configuration from the server itself, of course, where other forms of 2FA (e.g. certificate-based) might, but protecting servers from bad actors is a whole separate essay.

× × × ×

Syncthing

This last month or so, my digital life has been dramatically improved by Syncthing. So much so that I want to tell you about it.

Syncthing interface via Synctrayzor on Windows, showing Dan's syncs.
1.25TiB of data is automatically kept in sync between (depending on the data in question) a desktop PC, NAS, media centre, and phone. This computer’s using the Synctrayzor system tray app.

I started using it last month. Basically, what it does is keeps a pair of directories on remote systems “in sync” with one another. So far, it’s like your favourite cloud storage service, albeit self-hosted and much-more customisable. But it’s got a handful of killer features that make it nothing short of a dream to work with:

  • The unique identifier for a computer can be derived from its public key. Encryption comes free as part of the verification of a computer’s identity.
  • You can share any number of folders with any number of other computers, point-to-point or via an intermediate proxy, and it “just works”.
  • It’s super transparent: you can always see what it’s up to, you can tweak the configuration to match your priorities, and it’s open source so you can look at the engine if you like.

Here are some of the ways I’m using it:

Keeping my phone camera synced to my PC

Phone syncing with PC

I’ve tried a lot of different solutions for this over the years. Back in the way-back-when, like everybody else in those dark times, I used to plug my phone in using a cable to copy pictures off and sort them. Since then, I’ve tried cloud solutions from Google, Amazon, and Flickr and never found any that really “worked” for me. Their web interfaces and apps tend to be equally terrible for organising or downloading files, and I’m rarely able to simply drag-and-drop images from them into a blog post like I can from Explorer/Finder/etc.

At first, I set this up as a one-way sync, “pushing” photos and videos from my phone to my desktop PC whenever I was on an unmetered WiFi network. But then I switched it to a two-way sync, enabling me to more-easily tidy up my phone of old photos too, by just dragging them from the folder that’s synced with my phone to my regular picture storage.

Centralising my backups

Phone and desktop backups centralised through the NAS

Now I’ve got a fancy NAS device with tonnes of storage, it makes sense to use it as a central point for backups to run fom. Instead of having many separate backup processes running on different computers, I can just have each of them sync to the NAS, and the NAS can back everything up. Computers don’t need to be “on” at a particular time because the NAS runs all the time, so backups can use the Internet connection when it’s quietest. And in the event of a hardware failure, there’s an up-to-date on-site backup in the first instance: the cloud backup’s only needed in the event of accidental data deletion (which could be sync’ed already, of course!). Plus, integrating the sync with ownCloud running on the NAS gives easy access to my files wherever in the world I am without having to fire up a VPN or otherwise remote-in to my house.

Plus: because Syncthing can share a folder between any number of devices, the same sharing mechanism that puts my phone’s photos onto my main desktop can simultaneously be pushing them to the NAS, providing redundant connections. And it was a doddle to set up.

Maintaining my media centre’s screensaver

PC photos syncing to the media centre.

Since the NAS, running Jellyfin, took on most of the media management jobs previously shared between desktop computers and the media centre computer, the household media centre’s had less to do. But one thing that it does, and that gets neglected, is showing a screensaver of family photos (when it’s not being used for anything else). Historically, we’ve maintained the photos in that collection via a shared network folder, but then you’ve got credential management and firewall issues to deal with, not to mention different file naming conventions by different people (and their devices).

But simply sharing the screensaver’s photo folder with the computer of anybody who wants to contribute photos means that it’s as easy as copying the picture to a particular place. It works on whatever device they care to (computer, tablet, mobile) on any operating system, and it’s quick and seamless. I’m just using it myself, for now, but I’ll be offering it to the rest of the family soon. It’s a trivial use-case, but once you’ve got it installed it just makes sense.

In short: this month, I’m in love with Syncthing. And maybe you should be, too.

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