[EdLUG] ssh handshake issues in Ubuntu 22.04

[Malcolm Durie]


I use a RaspberryPi3B+ as a pihole add blocker server on my home network running headless so access it by ssh for maintenance etc. 

It went well until i upgraded the OS to the latest Ubuntu Server LTS 22.04 recently. I have used Ubuntu as the server as it proved more reliable for long term use compared to Raspbian. 

I cannot now ssh the server from SSH apps on my ipad. I get an error “Encryption exchange with host failed”, On IOS apps and from windows pc does not always connect. 

On my pi4B I have run Raspberry Pi OS that is the same generation of the kernel 5.15 and Debian11 and this works ok in both the 32bit and 64 bit versions. 

Ssh still works ok from macos and linux devices to the ubuntu server?

Is there some specific ssh update specific  to Ubuntu?

I have not been able to find any documentation about this issue with ssh authentication and handshaking changes?

Thanks

Malcolm