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Upgrade to a RPi4 plus SSD

Beitragsautor Von Gerhard Vogt
Beitragsdatum August 22, 2020
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After having some trouble with my existing system I decided to upgrade to a RPi4 powered system, together with a SSD as a new storage medium.

As I wanted to migrate the old data to the new system I had to come up with a strategy how to get there.

First I prepared the RPi4 to boot from another storage device as the standard SD card, based on the following tutorial.

Then I flashed the SSD with the currently available latest raspbian buster version and attached it to the blue USB 3.0 slot.

While booting I got some errors from the fsck utility, but after some booting time it ran through. I tested a bit further and was rebooting a few times. Every time another error occured and finally – after some hours – I had the idea to put an USB hub between the SSD and the RPi4. So it looks that the USB hub solves the problem, although it’s not even powered. Weird, isn’t it?

And, voila, from now onwards the booting and also the working of the system was perfect.

Now as the base system was running and the RPi4 was able to boot from the SSD I had to migrate the software and the data of the old system to the new system.

For this I used the backup of the old system I made with raspiBackup, just flashing it completely onto the SSD.

The final step was now, to copy the .elf and .dat files from the still existing boot partition of the SD card to the boot partition of the SSD, so that the RPi is booting from the SSD.

Now the system is up and running and it is really very fast 🙂

But hold on, we are not done yet!

IP and DNS entries

I have setup the new system with a new IP address, running in parallel to the RPi3 live system. I thought, „OK, let’s just switch the port forwarding of the router to the new IP address with the ports 80, 443, for IPV4 and IPV6 addresses and it should work.“

Unfortunately it did not work.

I forgot, that I had to reconfigure also the DNS forwarding at my domain hoster with updating the CNAME. And, unfortunately again, there is a time to live (TTL) set for the CNAME entry. So it’s much recommended to set this TTL value to the lowest possible value some days in advance. Otherwise it takes a few hours that the CNAME changes are taking effect through all the DNS servers.

So have fun to upgrade to a RPi4 on yourself 🙂

Schlagwörter Raspberry pi, Raspbian, rpi

Blog Podcast

Human genome and evolutionary dynamics

Beitragsautor Von Gerhard Vogt
Beitragsdatum August 19, 2020
Keine Kommentare zu Human genome and evolutionary dynamics

A wonderful podcast again! This time about the human genome and evolutionary dynamics.

If you wanna dive into the details of Covid-19 keep on listening.

Here are some fantastic statements from the podcast:

„Evolution is messy and ruthless.“

„Intelligence is always seen in the eye of the beholder.“

„A virus is not intelligent, but the process of the evolution is intelligent as the DNA has the only goal to spread.“

„Let’s embrace people to break things.“

„Let’s target robustness of systems.“

„The ambiguity of language maybe the source of creativity.“

https://pca.st/episode/c551b505-5f68-4ee2-b549-9584956cf14d

Schlagwörter COVID-19

Blog Software

Raspberry Pi backup

I was struggeling recently as I somehow „destroyed“ the operating system of my RPi. So I wanted to setup a better Raspberry Pi backup solution.

The existing solution saved me, true, but we can do better. I had the following setup running:

Updraft for all the wordpress content. This really saved me. A very nice backup solution. The restore was easy and worked. Google drive is used as storage for the backup.
A regular backup of the mysql db with automysqlbackup. The backup also worked, but it’s quite difficult to make a restore. This is recommended if you have other applications except wordpress that use the database.
The backup was saved to an USB flash drive mounted to the RPi.
An rsync backup of the most important config files under /etc.
The backup was saved to the same USB flash drive mounted to the RPi.

Raspberry Pi backup — Backup, Backup, Backup,…

New backup solution

The new solution now looks like that:

I’m still using Updraft for all the wordpress content and system. Google drive is used as storage for the backup.
Optional: A regular backup of the mysql db with automysqlbackup. The backup also works, but it’s quite difficult to make a restore. If you are starting from scratch you have to create the database, users and privileges before importing the content of the database.
This is recommended if you have other applications except wordpress that use the mysql database.
The backup is saved to an USB flash drive mounted to the RPi.
The script raspiBackup saves now both partitions of the RPi file system. Mine are both located on a hard drive, but of course it can be on the S(S)D card as well.
So you need a mounted drive where you wanna save the complete backup and for the restore you need either a linux system with the script running or another RPi.
If you are using the „dd“ method you can also use a windows system.

If you wanna be notified when the backup was running, hopefully successful, you need an mail client.

I was trying to install ssmtp as an e-mail client, but was not successful, so I switched to the – for me – well known exim4.

You can install it based on this tutorial.

Be aware when using it with a google mail account that you have to enable the feature lesssecureapps.

With that solution I’m able to restore the live RPi system reliably much faster with all the data.