Hi Philip,

Am Sonntag, 10. März 2019, 08:25:54 CET schrieb Philip Webb:
> I updated Ssh yesterday :
> [...]
>   ssh x.y.z
>   Unable to negotiate with 128.100.160.1 port 22: no matching key
> exchange method found. Their offer:
> diffie-hellman-group-exchange-sha1,diffie-hellman-group1-sha1
ssh tells you straight forward what the issue is: Within the key exchange
at the begin of the communication there was no way to establish a 
connection between the server and the client, probably because the client 
has a more secure setup than the server. This happens mostly due to old ssh 
versions serverside.

You can find solutions pretty fast by just searching for "Their offer: <key 
exchange offers>", e.g. https://unix.stackexchange.com/questions/340844/
how-to-enable-diffie-hellman-group1-sha1-key-exchange-on-debian-8-0

(Please enable legacy and possible less secure key exchange formats and 
ciphers only per server and not globally - and if possible upgrade the SSH 
server version.)

> 'x.y.z' disguises the site's URL, which doesn't seem to be a problem.
That is indeed perfectly fine; you might want to hide the IP address in the 
future aswell ;-)


Greetings,
Nils

-- 
GPG fingerprint: '00EF D31F 1B60 D5DB ADB8 31C1 C0EC E696 0E54 475B'
Nils Freydank