[SOLVED] sshd: "algorithm negotiation fail"

[SOLVED] sshd: "algorithm negotiation fail"

Postby vmunich » Mar 24th, '20, 21:53

Hi everyone,

I installed OpenSSH on my Mageia machines and I can login using ssh from one machine into the other.

What I cannot do is e.g. use a different system (android smartphone...) for logging into any of the Mageia machine using SSH...

I always get the message "algorithm negotiation fail"

How should I configure my SSH server on the Mageia machines so that they can be reach by most other device - and still be secure ???

Thanks a lot !
Last edited by vmunich on Mar 25th, '20, 16:01, edited 1 time in total.
Posts: 29
Joined: Jan 11th, '13, 12:35

Re: sshd: "algorithm negotiation fail"

Postby doktor5000 » Mar 24th, '20, 23:45

The question is probably more, what ssh client are you using on your smartphone, what algorithms does it support, and how can you make it accept the more secure algorithms ?
A log excerpt of a connection attempt would show most of that, maybe you can try to post one.
Cauldron is not for the faint of heart!
Caution: Hot, bubbling magic inside. May explode or cook your kittens!
Disclaimer: Beware of allergic reactions in answer to unconstructive complaint-type posts
User avatar
Posts: 16080
Joined: Jun 4th, '11, 10:10
Location: Leipzig, Germany

[SOLVED] Re: sshd: "algorithm negotiation fail"

Postby vmunich » Mar 25th, '20, 16:00

Thanks Doktor for your reply.
It seems that th eproblem lies with the android client (JuiceSSH).

I found the following possible explanation online:
" the SSH library we are using (JSch) is ignoring best practices specified in RFC4253. Specifically, when it encounters an unknown SSH message type, rather than sending SSH_MSG_UNIMPLEMENTED and continuing, it's throwing an exception and bailing out."

I tried connecting per SSH using another android client (Termius) and it works perfectly...

Thanks, problem solved
Posts: 29
Joined: Jan 11th, '13, 12:35

Return to Networking

Who is online

Users browsing this forum: No registered users and 1 guest