Permission denied when running script via ssh

Question

I wrote a script which downloads via scp and installs some packages. SSH keys are added to host and when I run

[root@HostB ~]# ./myscript

everything is ok and packages are downloaded via scp without asking for password.

I need to run this script via ssh but when I try

[root@HostA ~]# ssh root@HostB "./myscript"

I get Permission denied (publickey,password) error.

When I'm trying to use ssh -t I get a password enquiry in place when scp command in myscript is executing.

Answer 1

Answer= Add "bash"

How to SSH into a Computer and Execute a Script from Jenkinsfile: The file is called "Shell Script.sh" in directory "/home/username/Shell Script Directory"

From Jenkinsfile:

sh "sudo ssh -i /home/user/myPemFile.pem -o StrictHostKeyChecking=no -n [email protected] \"bash /home/username/Shell\\ Script\\ Directory/Shell\\ Script.sh\" "

Answer 2

My guess would be because you don't have PasswordAuthentication set to yes.

PasswordAuthentication yes

Add this to the sshd_config on the machines and try again. This should prompt for password.

Another solution would be to take the contents of ~/.ssh/id_rsa.pub on HostA and add it to the file ~/.ssh/authorized_keys on the HostB

Now that you have password authentication enabled, you can install the authorized keys with this command:

ssh-copy-id HostB

Answer 3

You mention that you're using scp inside your script to download packages. Your problem is with that bit. The issue is that, when you run ssh in this form:

ssh user@host command

... there is no pseudo terminal allocated to the script that is running. scp tries to prompt for a password, but it needs a pseudo terminal for that, so without one, you get the permission denied error (which is coming from a failed password authentication attempt). If you use ssh -t, then there is a pseudo terminal, and the password prompt works. What you need to figure out is why scp is prompting for a password when run remotely, but not when run from an interactive ssh session. That's a different question.

Answer 4

Permission denied (publickey,password) error

Its got nothing to do with the permissions on the script. You are failing to establish an ssh connection. Try just getting a shell on the remote system first.

ssh -vv root@HostB

BTW it's generally not a good idea to allow direct access to the root account via ssh - and the error you have shown is what one would expect if the sshd is configured with PermitRootLogin=No. The right way to solve this is to provision an acocunt with appropriate sudo privileges and use that to run the command.

Answer 5

It sounds like it still wants you to input the password. When you SSH to HostB from HostA, does it ask for a password?

If it does, you will need to change your ssh_config file (/etc/ssh/sshd_config on RHEL/Centos) to have:

PasswordAuthentication no

If PasswordAuthentication is set to yes, it will always prompt you for a password.

Answer 6

Try this:

ssh root@hostb 'bash -s' < local-script.sh