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Thanks Bill. I will be having another contact with a school in Canada on Tuesday. This ISS contact is scheduled to begin at 9:31 a.m. ET. We will post more information about this contact shortly,
Fred, AB1OC
The Public key mentioned above is generated randomly as part of the SSH key pair creation process. You can learn more about generating SSH key pairs here –
https://www.ssh.com/academy/ssh/keygen
When we first set up Linux on on RPi, we generated an SSH key pair. Later, we changed the SSH key to use a different pair that I generated on my macOS system. This caused the fingerprint for the server to change and I had to edit .ssh/known_hosts to remove the old fingerprint so a new one could be generated.
Fred, AB1OC
Here is a little more about how the SSH fingerprint is generated –
The fingerprint is based on the host’s public key, usually based on the
/etc/ssh/ssh_host_rsa_key.pubfile. Generally, it’s for easy identification/verification of the host you are connecting to.You can view the contents of the file by running
cat /etc/ssh/ssh_host_rsa_key.pub. To view that public key in fingerprint format, runssh-keygen -lvf /etc/ssh/ssh_host_rsa_key.pub.If the fingerprint changes, the machine you are connecting to has changed their public key. This may not be a bad thing (happens from re-installing ssh), but it could also indicate that you are connecting to a different machine at the same domain/IP (happens when you are connecting through something like a load balancer) or that you are being targeted with a man-in-the-middle attack, where the attacker is somehow intercepting/rerouting your ssh connection to connect to a different host which could be snooping your username/password.
Bottom line: if you get warned of a changed fingerprint, be cautious and double-check that you’re actually connecting to the correct host over a secure connection. Though most of the time this is harmless, it can be an indication of a potential issue.
Hi Dave,
Got it. What we are doing at this point in the setup video is making the initial connection between our Home Server and our PC. The connection is encrypted using SSH (the command we are running to make the connection).
The first time we access our Raspberry Pi from our PC, a unique fingerprint is generated which identifies the specific hardware device our server is running on. Subsequent connections from our PC to the Pi will confirm that the same fingerprint is supplied each time we connect.
If a hacker were to get onto our network and try to emulate our server, their device would not be able to generate the correct fingerprint and our PC would refuse to connect via SSH.
Some SW updates can sometimes cause this fingerprint to change. If this happens, you can edit a file on your PC in your home directory called .ssh/known_hosts to remove the recorded fingerprint for your server and set a new one.
You can learn more about SSH and fingerprints here –
https://www.jscape.com/blog/ssh-key-fingerprint
Fred, AB1OC
Hi Dave,
I am not sure what you are referring to here. Could you take a look at the initial setup video here –
https://homelab.anita-fred.net/raspberry-pi-home-server/#OS_and_CasaOS_Installation
and let me know the time in the video you saw this.
Fred, AB1OC
Brain and the WFD team met last evening, and our plans for WFD 2025 are shaping up nicely. Attached is a copy of our current plan.
https://www.n1fd.org/wp-content/uploads/2024/12/WFD-Plans.pdf
I will provide a summary of two projects –
1) A portable ground station for IO-117 (A DX Satellite)
2) Recent Computing and Networking upgrades at AB1OC-AB1QB
Fred AB1OC
Hi Tom,
I’m not sure that I completely understand the problem that you are trying to solve. Are you trying to use a special call sign as your to make FT8 contacts? Can just change your current callsign in the FT8 setup area where you current AB1NS callsign is set to the one for the special event? I do this all the time when I operate as N1FD. When I am done, I just change the callsign back to mine.
I hope that this helps.