626
votes
How to run the SSH server on a port other than 22
If you are on Linux system and you want connect to an SSH server on port 26 you can use the following command.
ssh user@192.168.1.1 -p 26
Note:
Replace server IP with the IP Address or DNS name of ...
- 6,493
414
votes
Accepted
Ubuntu 16.04 ssh: sign_and_send_pubkey: signing failed: agent refused operation
Looks like an ssh-agent is running already but it can not find any keys attached. To solve this add the private key identities to the authentication agent like so:
ssh-add
Then you can ssh into your ...
- 20.2k
370
votes
Accepted
SSH returns: no matching host key type found. Their offer: ssh-dss
The version of OpenSSH included in 16.04 disables ssh-dss. There's a neat page with legacy information that includes this issue: http://www.openssh.com/legacy.html
In a nutshell, you should add the ...
- 6,818
237
votes
Really verbose way to test Git connection over SSH?
Environment variable
From Git version 2.3.0, you can use the environment variable GIT_SSH_COMMAND and pass the -v verbose argument like this:
GIT_SSH_COMMAND="ssh -v" git clone example
To be extra ...
- 38.7k
137
votes
Accepted
rsync over ssh "error in protocol data stream" (code 12). ssh works
You can also get this error if you specify a remote path that doesn't exist.
I got this error on OS X:
$ rsync -avz public/ static:apps/myapp.com
building file list ... done
rsync: connection ...
- 1,486
135
votes
"This account is currently not available" error when trying to ssh
While I agree with the others that allowing login through SSH through the www-data user is generally a bad idea, once you've logged in with a normal user it may be useful to run multiple commands ...
- 1,451
129
votes
SSH Permission denied (publickey)
Sometimes the issue comes from permissions and ownership. For instance, if you want to log in as root, /root, .ssh and authorized_keys must belong to root. Otherwise, sshd won't be able to read them ...
- 1,441
122
votes
How do I copy files that need root access with scp?
Quick way
From server to local machine:
ssh user@server "sudo cat /etc/dir/file" > /home/user/file
From local machine to server:
cat /home/user/file | ssh user@server "sudo tee -a /etc/dir/file"...
- 1,321
118
votes
Login SSH with .ppk file on Ubuntu Terminal
If you only have .ppk file then it would be useful to create a .pem file and then connect to your server using that.
In you Ubuntu computer, install putty-tools with the following command:
sudo apt-...
- 1,301
115
votes
114
votes
Accepted
ssh -L (error: bind: Address already in use)
Couldn't you just kill whatever is using that port?
lsof -ti:5901 | xargs kill -9
lsof -ti:5901 to find whatever is using port 5901.
Pass the whole thing to kill -9 to kill whatever was using ...
- 2,076
111
votes
Why am I getting a "port 22: Connection refused" error?
I went through this issue and finally got appropriate answer.
sudo apt-get update
sudo apt-get install openssh-server
sudo ufw allow 22
Then went into raspi-config in a terminal window and enabled ...
- 1,211
107
votes
SSH returns: no matching host key type found. Their offer: ssh-dss
If you came here because Bitbucket returns the following after an update to OpenSSH 8.8:
Unable to negotiate with <ip address> port 22: no matching host key type found. Their offer: ssh-rsa,ssh-...
- 1,171
94
votes
Enter SSH passphrase once
Short answer
Use AddKeysToAgent and add the following to your .ssh/config at the beginning:
AddKeysToAgent yes
and run git/ssh/... If it's not enough, check your ssh version and check that ssh-agent ...
- 2,218
82
votes
Accepted
How to disable welcome message after SSH login?
The welcome messages are generated by the files residing in /etc/update-motd.d/.
From man update-motd:
Executable scripts in /etc/update-motd.d/* are executed by pam_motd(8)
as the root user at ...
- 88.8k
81
votes
How do I SSH to machine A via B in one command?
You could use the -J command line option:
ssh -J user@machineB user@machineA
From man ssh:
-J [user@]host[:port]
Connect to the target host by first making a ssh connection to
the jump ...
- 1,734
80
votes
/etc/sudoers file corrupted and I can't run 'pkexec visudo' over SSH
I ran into this problem also and with some digging, found a working solution. The original solution is from this github issue for NixOS by EstalillaJ.
Open two ssh sessions to the target server.
In ...
- 901
79
votes
Ubuntu 16.04 ssh: sign_and_send_pubkey: signing failed: agent refused operation
I had the same problem (same symptoms)
sam@xxxxx:~/.ssh$ ssh centos@123.123.123.123
sign_and_send_pubkey: signing failed: agent refused operation
Permission denied (publickey,gssapi-keyex,gssapi-...
- 901
75
votes
Login SSH with .ppk file on Ubuntu Terminal
You can convert a .ppk file in ubuntu with installing putty-tools. So
apt-get install putty-tools
Then youn can convert the .ppk file with puttygen to OpenSSH's format like so:
puttygen <the_key....
- 1,426
73
votes
Accepted
How does using the tilde work as a shortcut to my home directory?
~ is your home directory.
~foo is the home directory of user foo, if such a user exists, or just a directory named ~foo, if that user doesn't exist.
Hence, in:
scp ~Desktop/Volenteer.png jay@...
- 189k
68
votes
Should I always restart the system when I see "System restart required"?
Should I always restart the system when prompted to?
You may view the list of packages that require a restart with:
more /var/run/reboot-required.pkgs
Based on the list, you can decide whether it ...
- 3,240
67
votes
Accepted
Start SSH automatically on boot
Have you tried just simply setting
sudo systemctl enable ssh
?
That's how I have my ssh set to run at start up.
****I'm leaving in the above part of the answer in case it's helpful for others who ...
- 1,016
66
votes
Accepted
Found SSH Backdoor on VServer. What to do?
This is what you should do on all the systems that you've had this sniffer.tgz on: Nuke Them From Orbit immediately, and start over from a clean installation. (That is, destroy the system(s), ...
- 70.4k
64
votes
Accepted
How to use existing SSH key on my newly installed Ubuntu
If you have a copy of your ssh keys (e.g., on a USB stick) then simply copy the key files to the ~/.ssh/ directory.
E.g.,
cp /path/to/my/key/id_rsa ~/.ssh/id_rsa
cp /path/to/my/key/id_rsa.pub ~/.ssh/...
- 6,952
63
votes
Create alias for ssh connecting
Use the intended way and write the options and aliases into ~/.ssh/config:
Host 1
Port 12345
User my_user
HostName 123.123.123.1
Host 2
Port 12345
User my_user
HostName 123.123.123.2
...
- 6,435
58
votes
Accepted
What is the simplest way to have remote GUI access to Ubuntu 16.04 “server” from Ubuntu 16.04 “desktop”?
ssh -X
In the server you need an ssh server, for example openssh-server and at least some basic X tools, for example xinit and fluxbox (and the programs and libraries that they need). You must also ...
- 43.7k
57
votes
How to disable welcome message after SSH login?
Another way that does not require administrative rights is to place an empty file called
.hushlogin
into your $HOME directory (using for example touch ~/.hushlogin).
The downside to this solution is ...
- 671
54
votes
How do I restart the SSH service?
15.04 and newer:
Use this command:
sudo systemctl restart ssh
To restart the SSH server/daemon.
Going forward with systemd starting with Ubuntu 15.04, you now use this syntax to stop, start, or ...
- 1,496
54
votes
Error `could not load host key` when trying to recreate SSH host keys
None of the answers above worked for me. I fixed my ubuntu system by doing the following:
/usr/bin/ssh-keygen -A
- 641
Only top scored, non community-wiki answers of a minimum length are eligible