kex_exchange_identification: Connection closed by remote host

Question

I've wanted to connect my share hosting with ssh. So I generate an ssh key in the ssh action of cpanel and authorized it. Then I've downloaded the private key and drop it in the ./ssh folder of my MacBook.I've used this code to connect my host.

ssh -p 2083  username@host IP

but I got this error:

kex_exchange_identification: Connection closed by remote host

How can I solve my problem?

Stickinthemud

There can be many causes. One possibility is that the VM is shut down, which can easily happen in AWS or Azure if you have auto shutdown enabled. – Coimbatore

Answer 1

I run into a similar case with a small computer I have in my desk. What I did to debug the issue was to run sshd -t, which runs the sshd daemon in debug mode. This command reported that the permissions of my keys were invalid. All I had to do then was to go in the folder where the keys are stored and issue chmod 0600 <your_ssh_keys>. Maybe the action you run generated things with the wrong permissions too.

Buccaneer

chmod 400 authorized_keys – Mauri

Answer 2

I got this error when using docker command with remote host

docker -H ssh://user@server compose up

after some digging i found on my remote server in auth logs (/var/log/auth.log) this:

Aug  8 14:51:46 user sshd[1341]: error: beginning MaxStartups throttling
Aug  8 14:51:46 user sshd[1341]: drop connection #10 from [some_ip]:32992 on [some_ip]:22 past MaxStartups

This lead me to change MaxStartups settings in /etc/ssh/sshd_config. After restarting ssh service everything worked like a charm.

Exhalation

I am also facing the issue with docker. What value you gave to MaxStartups? – Nassir

Answer 3

I had same problem and it was happend as I use ProxyCommand in ssh config file. In my case the Host was not defined correctly which then caused the same error!

Hebetude

Answer 4

first, make sure if the hostname is correct. A typo either in the cmd or configfile gives this error.

then, check the sshd log in the host, to find the issues.

Stoss

Answer 5

Not so sure if my solution is working for yours. For me, I plan to connect to github via ssh. The same error occurs. I find the solution in https://github.com/orgs/community/discussions/55269 My config file content is as below.

#Windows
ProxyCommand "C:\APP\Git\mingw64\bin\connect" -S 127.0.0.1:51837 -a none %h %p

#MacOS
#ProxyCommand nc -v -x 127.0.0.1:51837 %h %p

Host github.com
  User git
  Port 443
  Hostname ssh.github.com
  # change the path here
  IdentityFile "C:\Users\Your_User_Name\.ssh\id_rsa"
  TCPKeepAlive yes

Host ssh.github.com
  User git
  Port 443
  Hostname ssh.github.com
  # change the path here
  IdentityFile "C:\Users\Your_User_Name\.ssh\id_rsa"
  TCPKeepAlive yes

Abram

Answer 6

In my case the host was also the reason - I used gitea as git server and the .ssh folder and all certs in it required to be not accessible for everyone.

This makes totally sense, but I wished that the error message would give a better hint!

Ardatharde