I've been self-hosting Nextcloud for sometime on Linode. At some point in the not too distant future, I plan on hosting it locally on a server in my home as I would like to save on the money I spend on hosting. I find the use of Nextcloud to suit my needs perfectly, and would like to continue using the service.
However, I am not so knowledgeable when it comes to security, and I'm not too sure whether I have done sufficient to secure my instance against potential attacks, and what additional things I should consider when moving the hosting from a VPS to my own server. So that's where I am hoping from some input from this community. Wherever it shines through that I have no idea what I'm talking about, please let me know. I have no reason to believe that I am being specifically targeted, but I do store sensitive things there that could potentially compromise my security elsewhere.
Here is the basic gist of my setup:
- My Linode account has a strong password (>20 characters, randomly generated) and I have 2FA enabled. It required security questions to set up 2FA, but the answers are all random answers that has no relation to the question themselves.
- I've disabled ssh login for root. I have instead a new user that is in the sudo usergroup with a custom name. This is also protected by a different, strong password. I imagine this makes automated brute-force attacks a lot more difficult.
- I have set up fail2ban for sshd. Default settings.
- I update the system at the latest bi-weekly.
- Nextcloud is installed with the AIO Docker container. It gets a security rating A from the Nextcloud scan, and fails on not being on the latest patch level as these are released slower for the AIO container. However, updates for the container is applied automatically, and maintaining the container is a breeze (except for a couple of problems I had early on).
- I have server-side encryption enabled. Not client-side as my impression is that the module is not working properly.
- I have daily backups with borg. These are encrypted.
- Images of the server are also daily backed up on Linode.
- It is served by an Apache web server that is exposed to outside traffic with HTTPS with DNS records handled by Cloudflare.
- I would've wanted to use a reverse proxy, but I did not figure out how to use it together with the Apache server. I have previously set up Nginx Reverse Proxy on a test server, but then I used a regular Docker image for Nextcloud, and not the AIO.
- I don't use the server to host anything else.
I have Nextcloud hosted internally in a podman container environment. To answer some of your more security related questions, here's how I have my environment set up:
Cloudflare free tier with my own domain to proxy outside connections to the public domain name, and hide my external IP.
A DMZ proxy server with a local traefik container with only ports required to talk to the internal Nextcloud server allowed, and inbound 443 only allowed from the internet (cloudflare).
An Authelia container tied to the Nextcloud container using "Two-factor TOTP" app addon. Authelia is configured to point to a free DUO account for MFA. The TOTP addon also allows other methods of you want to bypass Authelia and use a simply Google auth or other app. I'll be honest, this setup was a pain but it works beautifully when finally working.
Note: Using Authelia removes Nextcloud from the authentication process. If you login through Authelia, if set up correctly it will pass the user information to Nextcloud and present thier account. There is a way to have "quadruple" authentication of you really want it, where you log in through Authelia, Authelia MFA, then Nextcloud and Nextcloud MFA, but who would want that? Lol.
Another Note: If Authelia goes down for whatever reason, you can still log in through Nextcloud directly.
I have all of my containers set to automatically pull updates with the latest tag. This bites me sometimes of major changes happen, but it's typically due to traefik or mariadb changes and not Nextcloud or Authelia.
I have my host operating system set to auto update and reboot once a week in the early morning.
My data is shared through an NFS connection from my NAS that only allows specific IPs to connect. I'd like to say I'm using least privileged permissions in the share, but it's a wide open share as my NFS permissions are not my strong suite.
Hope the above helps!
Thanks for your answers!
Setting up auto update and reboot once a week seems smart. Do you set this up with cron?