Backing up a Pi (with USB HDD)

Pi Backup

Time for another text based pi article.. sorry!

Attach the USB disk to the pi.

Next download pi shrink

sudo chmod +x
sudo mv /usr/local/bin

Next check for the correct paths


Now run a dd copy to create the image

sudo dd if=/dev/mmcblk0 of=[mount point]/myimg.img bs=1M

Finally shrink the image

sudo -z myimg.img

You now have a size optimized image that you can restore using the “official” pi image writer software. You can stick this in a cron job to create a regular image backup of any pi.


If you are cloning to test or deploy into another Pi, you will need to delete the VNC config or you will get a “cloned” error in the VNC client and it could stop working. Luckily it’s simple to fix, on the cloned machine do the following:

sudo systemctl stop vncserver-x11-serviced
sudo rm -rf /root/.vnc
sudo systemctl start vncserver-x11-serviced

ZFS Expand with new disk

I realised that one of my 3Tb drives was very, very old. It wasn’t failing yet, but it would probably be best to proactively replaced it. The other drive in the mirror is a 4Tb drive, so I took the opportunity to buy another 4Tb drive and add it to the ZFS mirror… This was so simple it’s scary. Firstly I removed the old drive from the mirror.
#zpool detach <Pool Name> <Device to Remove>

i.e #zpool detach SATAPool sdd
Then I shutdown the machine removed the old drive and put the new one in. When the box rebooted I added the new disk to the mirror.
#zpool attach <Pool Name> <Existing Disk><New Disk>

i.e #zpool attach SATAPool sdc sdd
I let it resilver… but it didn’t auto expand. The main reason for this was I didn’t have autoexpand turned on.
#zpool set autoexpand=on <Pool Name>
This didn’t fix the issue, but it did show the space was available.  The next thing I did was to use the online -e on every disk in the mirror.
#zpool online -e <Pool Name> <Disk Name>

i.e. #zpool online -e SATAPool sdd
And then I had an extra Tb to play with!

Hyper-v to Proxmox

This one is going to be word and code heavy.

Firstly shutdown the hyper-v gen2 VM.

Copy the VHDX to the proxmox server, remember you will need twice the space of the VHDX available temporarily to completed the move.

Create the VM on Proxmox, you will need to create it using a OVMF (UEFI) BIOS. You will also need to create a 1Gb virtio hard disk (again this is temporarily)

Make a note of the VM ID (i.e. 103), you’ll need this to import the hard disk.

Once the VHDX is copied across you need to import the disk

 qm importdisk VMID SORCEDISK.vhdx DATASTORE --format qcow2

i.e. qm importdisk 103 /tmp/data.vhdx SATA –format qcow2

This will then import the disk to the VM.

Next you need to head over to the VM in proxmox and attach the disk in the gui, you will need to install it as SATA or IDE (not virtio yet)

Boot the machine up into windows, install the latest tools, the temporary 1Gb disk we installed earlier will mean the virtio drivers are installed.

Shut the VM down, remove and reattach your windows drive as virtio, remove and delete the temporary 1Gb drive and turn the machine back on. If your machine had a static IP you will need to readd it, you may get a warning about it being assigned to another NIC. You can ignore this, however, I would recommend removing it at some point!

You can now delete the VHDX file you copied to the proxmox server

Job done!

Pi Rack & Pi KVM

Pi Rack

I decided that I wanted to tidy up my lack rack and put my two Pi’s rack mounted and out of the way. 

The first pi is a backup “server” it runs rsync and has a 3Tb USB drive, it is a staging server between my backups and OneDrive sync. This was easy to do, I printed one module and one pi rack module, works great! I am thinking I might PoE my rack mount Pi’s but this would mean two HATs and a PoE switch for the study.

The second Pi is my Pi KVM, this Pi is slightly more complex as it has some external components, these are mounted in a case, this case was too big for the module, so I 3D printed cases for the individual cases for the rack module. This has tidied it up and it now fits snuggly in the module.

I have done a lot of 3D printing to support the Pi Rack and Pi KVM components, you can see them on the media carousel, links are below.

The printed components are; Modular Pi Rack, USB power splitter case and HDMI to CSI-2 case.

Yummy, yummy Pis – May 2021 Update

Yummy, yummy Pi's - May 2021 Update

I’ve decided this will become a running update of the Pi’s I am using and what I am doing with them. Updates will be posted to the top of the page.

Pi Board and spare Pi

May 2021 – Update

A lot has changed in home Pi world… ESX for ARM has been released and I’ve been testing this, it works and is stable. Hopefully OPNSense will come to the Pi natively and then there will be some interesting opportunities to run Pi firewalls, I have looked at OpenWRT on the Pi, but prefer the completeness of the xSense ecosystem. I’ve upgraded a couple of Pi’s due to performance issues. I have also migrated the Pi 400 to SSD and it’s a lot quicker. I have been keeping an eye on SD card performance and have settled on Samsung Evo Plus and SanDisk Ultras / Extreme.  There appears to be a shortage of 2Gb Pi’s at the moment, I need an additional one to replace the Pi in the kitchen which I am currently using for the CCTV Pi.

A full list below:

    • Pi 4 1Gb – CCTV Pi (upgraded from a Pi 3+ for more streams (including 3D printer and new Eufy Cams)
    • Pi 4 2Gb – OctoPi (3D printer control)
    • Pi 4 2Gb – Pi Sync
    • Pi 4 2Gb – Pi KVM
    • Pi 4 2Gb – Caravan HA
    • Pi 4 2Gb – Caravan Pi
    • Pi 4 4Gb – Bedroom Kodi
    • Pi 400 – Study Pi

Spare Pi (s)

    • 2x Pi 2
    • 2x Pi 3+
    • Pi 4 8Gb (currently testing ARM ESXi)
    • Pi Pico
    • Zero WH
    • Zero
  • December 2020 – Update

In addition to the Pi’s below, I now have two more in use

    • Pi 2 – Backup Pi – Using rsync and rclone to manage all my backups locally and to sync to OneDrive for Business.
    • Pi 4 2Gb – Pi KVM – Find out more in this post 

I have also managed to purchase a Pi 2 v1.2 to go on the Pi versions board. This completes my collection of historical Pi Bs. When the next version of Pi’s come out the Pi 4’s will slowly be retired to the board!

I am also working on a project with Pi Zero WH’s to create a multizone audio system using Volumio, this project will make use of HifiBerry’s popular DAC Hats as well as some custom integration work. I currently have 3 Pi “audio zones” and am awaiting the hats to begin testing.

Spare Pi(s)

    • Pi 2, Pi 3+, Pi 4 8Gb
    • Pi Zero WH
    • Pi 2 1.2 ready for mounting

Retired Pi(s)

    • Pi 3+ – First home assistant server migrated to new proxmox host

Why no love for the Pi A or Compute module? Although I have a good collection of old Pi’s you may notice that I don’t have any Pi A or Pi Compute modules on the list. This is because I don’t use them! I’ve never had a use for the compute modules. I do have a Pi A in a wildlife camera, but this currently isn’t being used. I love the Pi B and Zero form factors which is why I use them the most, if I have a project that ever uses the other form factors, I may well collect the back catalogue of those too!

Original Post – November 5th

From the moment they were announced I knew that the way I did computing at home had changed. Ideal as test boxes, development, media players and now even mini ESX servers! I’ve used them for many things…

The Pi’s I currently have in use are:

    • Pi 4 1Gb – Kitchen LibreELEC 
    • Pi 4 2Gb – 2nd Device in Lego Room
    • Pi 4 4Gb – Bedroom LibreELEC
    • Pi 400 – 2nd Device in Study 
    • Pi 3+ – CCTV Viewer
    • Pi 3+ – Garage
    • Pi 3+ – Home Assistant 

I have used them for other projects in the past including getting started with Home Assistant, mini ESXi Server, custom automations, OSMC media player, Plex Server, learning things with Ali, Wildlife Cameras, the list goes on. I hope they are around for a long time to come!

In the gallery below you can see the latest Pi 400, my display of Pi’s from the original Pi to the Pi 3 B+ (with space for the Pi4 1, 2, 4Gb version… the 8Gb version will start a new board). Next are my Pi’s ready for use (Pi Zero WH, Pi 3 B+ and Pi 4 8Gb), I also have a Pi 2 in the cupboard should I need something older to play with and yes that is a ZX Spectrum +2 behind them. Finally my Pi Zero Board up to the latest Pi Zero WH. 

A Couple of PDFs…

Over the last couple of months I have relied on a couple of web articles to get me through particularly specific issues. I hope these sites will remain available forever… However, I have “printed” the sites to PDFs to make sure they are available should the sites disappear / migrate / melt… etc

pfSense - Mikrotik Open VPN

The key piece of information in this one is around the client specific override!

Unifi CK2+ Backup

How to backup a Unifi controller / CK2+ using the amazing rclone.

Proxmox vTPM Win 11

A guide for setting up vTPM for virtual machines running on proxmox 7

SES – SNS -Lamdba – Dynamodb – Alllll the AWS

I’ve been using SES for a while for sending email from servers.

A few months ago one of my servers was compromised and I discovered there is no such thing as good logging in SES…. whooops… Amazon suspended my account and this lead me to investigate how I could get some visibility of SES logging. This was considerably harder than I would have thought. There are no SMTP logs, not real recording of any information and no diagnostics. I nearly left SES for this, then I decided to use it as a learning opportunity to understand more about AWS & SES.

I used this guide to get it all working:

Hopefully this site never goes down, if so I will need to write my own guide! 

It’s easy to add extra fields to the database. These are all the objects available

Finally this docker image allows you to connect to dynamodb easily

The only thing I haven’t managed to do is find out which IAM user actually sent the email… I need to do more research on this to try and enhance my logging further.

Emergency Pi Zero

I have had a couple of requirements recently where I have needed to leave a device onsite for remote access. I initially thought that the best way to handle this would be to put a pi onsite that joined my VPN and then I could connect to all the machines on the remote network and do my troubleshooting like that…

I looked at my pi shelf and there looking all little and shiny was a Pi Zero… At this point I thought to myself… what do I actually need from this device.



I have a couple of Emergency Linux VMs on dedicated servers that run a lightweight GUI with pretty much just a web browser. These emergency VMs work with VNC, but VNC isn’t running all the time. You SSH into them and as part of the login it fires up a VNC session and when you log off it tears the connection down. So you SSH in with 2FA, this starts the VNC Server (with a password), when you finish you log out and it clears down the VNC session. I also installed a cron job that checks the devices external IP address and emails you when it changes (for when it goes into a residential setting).

Here’s how it’s setup

  • Install Raspberry OS (with desktop)
  • Enable SSH
  • Add to .bashrc

if [[ -n $SSH_CONNECTION ]] ;

  • Add to .bash_logout

 vncserver kill :1

When you arrive onsite, connect the pi zero to the network, add a port forward for port 22 and 5901 to the pi. Check the IP emailer works (see link above).

Migrations & Pi KVM

Over the last month I have migrated my home server from a Gen 8 HP Microserver to a Lenovo P500 workstation. There are many reasons for my migration the two biggest were that I was being constrained by the amount of RAM the Microserver could take (16Gb vs 512Gb), the processor was also becoming a bit of a bottle neck.

The second was that in my professional life I have moved from VMWare ESXi to Proxmox and my home lab was the only ESXi server that I was left managing, it also meant I wasn’t reflecting my professional install base so making it hard to test things.

Migrations are horrible, no matter how much planning you do, they take time and suck! No matter how many trials and tests you do there will always be something.

I used an old desktop PC with a 500Gb SATA drive and a 240Gb SSD to migrate all servers other than the Windows server (not enough space or grunt).

Although exceptionally boring and probably of no interest to anyone this was my migration plan..

  • Shutdown new host
  • NIC in new host
  • Check Second Network Card
  • Restore firewall
  • Copy all Proxmox machines from test proxmox host 
  • —–
  • Migration
  • Copy latest backup
  • Run Full backup c:\backups\backup.bat
  • Check USB disk on another PC
  • Close OneDrive
  • Restart PC
  • Check OneDrive is stopped
  • Shutdown VM
  • Convert System Disk
  • Check Proxmox Boot
  • —–
  • Move 2Tb disks to think station
  • Create new ZFS 2Tb for File Server
  • Boot File Server
  • Add 1.8Tb disk
  • Setup OneDrive if needed

20/02/2020 20:12 <JUNCTION> data [d:\data]
17/09/2020 08:48 <JUNCTION> media [D:\media]
17/09/2020 09:07 <JUNCTION> server backups [D:\backups]

  • Start OneDrive
  • Undisable Start with Windows OneDrive
  • Check shares
  • Remove “to watch” from backups
  • USB pass through
  • Setup Proxmox Backups (Exclude File Server d drive)
  • —–
  • Remove SSDs from Microserver and check
  • Rebuild Test Proxmox as Hobby PC with 240Gb SSD
  • —–
  • Take old Hobby PC
  • Check 120Gb SSDs
  • —–
  • 2FA for SSH and Proxmox on New Host
  • Add New Host to Nagios

This was all in a text file which I constantly updated and changed during the actual migration. It went well and there were only a couple of hiccups. The testing had paid off.


Hopper – New Host

Running proxmox with a number of Windows, Linux and BSD VMs.

  • Intel(R) Xeon(R) CPU E5-2609 v3 @ 1.90GHz (1 Socket)
  • 48Gb RAM
  • 2x 480Gb NAS SSD (ZFS), 2x 3Tb NAS SATA (ZFS), 1x 2Tb SATA (Backups)

The two USB cables – One going to an external HDD for file level backups, the second goes to the Pi KVM (for keyboard and mouse control)

The Pis

Tron – Pi 3+
4Tb USB Drive
Backup Pi (Rsync and rclone)

IP KVM – Pi 4 (2Gb)
Power/Data Splitter at the back
USB to HDMI Capture Card

Both are cabled into the network. The Pi 2 only has 100Mbps network, so it’s likely to need replacing soon to keep up with my internet, but for now it works! The Pi 3+ has “Gb network” however due to it using the same USB bus it can only realistically achieve 300Mbps.


This part of the project nearly got it’s own page… However, I don’t have much to say! One of the biggest drawbacks of migrating to the workstation was that I lost iLO (intelligent lights out / IPMI). I use iLO rarely but it is an incredibly useful when you do need it!

I was looking at aftermarket cards and IP based KVMs and they are expensive! I couldn’t justify the cost for a single host or the amount of time I use it. 

Then I came across Pi KVM, it looked hugely daunting until I started reading about it. For simple KVM features (and a host of other features) it was incredibly easy to build a Pi 4 KVM (you can use other Pi generations but you will need to do more work). Just one cable and an HDMI capture card and it just works! 

They are also developing their own Pi HAT with all the features (including power management (i.e. remote reboot)), I’ll probably buy one when they are released as I can think of a number of locations where a sub £100 KVM would be a life saver, especially with the remote reboot abilities.

Pi KVM can be found here:

Another Pi KVM project can be found here:

Bits I bought to make my Pi KVM

That was it! I had a case, power supply and SD card knocking about any way… When the hat is released I will need to think about a different case.

Pi KVM (Currently only using KVM, power control to come later)

Cloudkey 2+ Let’s Encrypt & Backups

Let's Encrypt using DNS on Cloudkey 2+ & Backups

Update: 16/02/2021 – For CK2+ off controller backups see this great how-to:

Update: 22/12/2020 – Use this script instead:

Stolen from the UI community site, but copied here in case Unifi change their forums again or it gets lost to the mists of time (Original URL:

Uses the domain, one shortcoming is that my current external DNS provider doesn’t have an API, so I have to manually complete the challenge every 3 months, but the whole process takes just a few minutes so I’m not too concerned.

All steps are performed directly on the Cloud Key.

First, install Git and obtain the Let’s Encrypt code:

cd /home

sudo apt-get update

sudo apt-get install git

git clone

Next, generate a certificate, specifying that you want to use a DNS challenge for proving ownership of the domain.

certbot certonly --manual --preferred-challenges dns --email --domains

In this example, is an internal hostname that resolves to my cloud key, and is an email address where I’d like Let’s Encrypt to send me a reminder when the certificate is about to expire.

Since we are using a DNS challenge, you will be prompted to create a TXT record with your DNS provider.  Let’s Encrypt will confirm that the DNS record is visible from their cloud infrastructure, thus proving you own the domain, and it will grant your certificate.

Next, stop unifi, since we’re about to mess with its certificates:

service unifi stop

Next, make a backup of the existing certificate data and remove it:

mkdir cert_backup

cp -r /etc/ssl/private/ cert_backup

rm /etc/ssl/private/cert.tarrm /etc/ssl/private/ssl-cert-snakeoil.key

Next, export your newly-granted Let’s Encrypt certificate into a format that Unifi understands:

cd /etc/letsencrypt/live/

openssl pkcs12 -export -in fullchain.pem -inkey privkey.pem -out cert.p12 -name unifi -password pass:your_certificate_password

Here, your_certificate_password is a temporary password of your choosing to protect the exported certificate.

Next, import the Let’s Encrypt certificate into the Unifi keystore:

keytool -importkeystore -deststorepass aircontrolenterprise -destkeypass aircontrolenterprise -destkeystore /usr/lib/unifi/data/keystore -srckeystore cert.p12 -srcstoretype PKCS12 -srcstorepass your_certificate_password -alias unifi

Note that aircontrolenterprise is the Unifi keystore password; it is not a password of your choosing.

In this command, /usr/lib/unifi/data/keystore is actually a symlink pointing to the /etc/ssl/private directory from earlier.

At this point, the Unifi Controller will work with your Let’s Encrypt certificate, but recall that the Cloud Key has a separate internal nginx-based webserver to handle OS configuration options.

Next, replace the default certificates in the location nginx is expecting them, and make sure the permissions are correct:

cp fullchain.pem /etc/ssl/private/cloudkey.crt

cp privkey.pem /etc/ssl/private/cloudkey.key

chown root:ssl-cert /etc/ssl/private/*

chmod 640 /etc/ssl/private/*

tar -cvf cert.tar *

chown root:ssl-cert cert.tar

chmod 640 cert.tar

Finally, restart nginx, protect and start the Unifi controller.

service nginx restart

service unifi-protect restart

service unifi start

At this point, they should come up and be using your Let’s Encrypt certificate.

Set a calendar reminder for ~2 months from now so you don’t forget to redo this before the certificate expires!

This guide simply re-arranges the hard work that others have done into a solution that fits my specific needs.  The author (pcoldren) used bits and pieces from the following resources while writing it: