ssh login without any prompt - unix

I have to login more then 150 sever and execute some unix commands.
The problem is, if I create a script which will run from one server and ssh login to 150 server and execute cmds and exit.
How can i login with any password prompt.
due to some reason i should not use ssh-keygen public and private key method , or use of some extra tool with bash line like "expect".
is there any normal way to do login through ssh in single command consisting username/password#servername like we have option in sqlplus and ftp.

There is a utility called sshpass that allows you to specify a password in the commandline.
Under Ubuntu/Debian install by using sudo apt-get install sshpass
sshpass -p 'abcedf' ssh joe#myserver.domain.com "df > ~/test; cat ~/test; rm ~/test;"
hope this helps

You can try setting up either ~/.shosts or /etc/ssh/shosts.equiv on each of your remote hosts. See man ssh under "AUTHENTICATION" for details.

Related

ssh command -T option

I'm wondering what the -T option in the following command does, cannot see this option in the manual somehow:
$ ssh -T git#gitlab.com
Welcome to GitLab, Simeon !
Could somebody explain?
I explained before what TTY was: a text terminal is needed when you open an interactive session to a remote server.
But: in the context of a remote Git repository hosting server (GitHub, Gitlab, BitBucket, ...), no remote server will ever allow you to open an interactive session (for security reason)
Then only reason why you would still do an ssh -T git#github.com would be to test if you are correctly authenticated, and the session would immediately end with:
Hi username! You've successfully authenticated,
but GitHub does not provide shell access.
Since no tty is needed for that test, you should use the -T option when making this test.

SSH AUTHENTIFACTION ISSUE

I am a newbie to embedded networking. I want to set arm board as a ssh server .From other boards(client boards connected in the network), I need to connect to this server board.
I have downloaded the openssh and cross compiled it for arm successfully.
I have used default sshd_config file and run sshd command in arm-board.
Command
"ssh-keygen -t rsa -f /usr/local/etc/ssh_host_rsa_key -N "" "
is used to genrate key.
My doubt is where can I set the username and password, so that I can login from a remote client using ssh command. I didn't find any document regarding this...?
Using ssh you are logging in as a normal system user. So you should add user using useradd command. You can change password using passwd command.

Google Cloud: Compute VM Instances

How do I get root access to my Google VM instance, and also how can I log into my VM Instance from my PC with a SSH client such as putty?
I would also like to add that I have tried to do sudo for things that need root access to do those things, such as yum or wget. But it does not allow me to do sudo, it asks me for the root password but I do not know how, or where I would be able to get the root password.
You can become root via sudo su. No password is required.
How do I use sudo to execute commands as root?
(splitting this off from the other answer since there are multiple questions within this post)
Once you connect to your GCE VM using PuTTY or gcloud compute instances ssh or even clicking on the "SSH" button on the Developers Console next to the instance, you should be able to use the sudo command. Note that you shouldn't be using the su command to become root, just run:
sudo [command]
and it should not prompt you for a password.
If you want to get a root shell to run several commands as root and you want to avoid prefixing all commands with sudo, run:
sudo su -
If you're still having issues, please post a new question with the exact command you're running and the output that you see.
sudo su root <enter key>
No password required :)
if you want to connect your gce (google-cloud) server with putty using root, here is the flow:
use puttygen to generate two ppk files:
for your gce-default-user
for root
do the followings on putty (replace gce-default-user with your gce username):
Putty->session->Connection->data->Auto-login username: gce-default-user
Putty->session->Connection->SSH->Auth->Private-key for authentication: gce-default-user.ppk
Then connect to server using your gce-default-user
make the following changes in sshd_config
sudo su
nano /etc/ssh/sshd_config
PermitRootLogin yes
UsePAM no
Save+exit
service sshd restart
Putty->session->Connection->data->Auto-login username: root
Putty->session->Connection->SSH->Auth->Private-key for authentication: root-gce.ppk
Now ou can login to root via putty.
If you need to use eclipse remote system and log-in as root:
Eclipse->windows->preferences->General->network Connection->SSH2->private-keys:
root-gce.ppk
Please try sudo su - on GCE.
By default on GCE, there is no password required to sudo (do as a substitute user). The - argument to su (substitute user) further simulates a full login, taking the target user (the default user for both is root) configured login shell and its profile scripts to set new environment parameters. You'll at least notice the prompt change from ending in $ to # in any case.
JUST GOT TO CLOUD SHELL BY CLICKING SSH
AND FOLLOW PASSWORD CHANGE COMMAND FOR ROOT USER USING SUDO :)
sudo passwd
and it will change the root password :)
then to becom root use command
su
type your password and become a root :)
How do I connect to my GCE instance using PuTTY?
(splitting this off from the other answer since there are multiple questions within this post)
Take a look at setting up ssh keys in the GCE documentation which shows how to do it; here's the summary but read the doc for additional notes:
Generate your keys using ssh-keygen or PuTTYgen for Windows, if you haven't already.
Copy the contents of your public key. If you just generated this key, it can probably be found in a file named id_rsa.pub.
Log in to the Developers Console.
In the navigation, Compute->Compute Engine->Metadata.
Click the SSH Keys tab.
Click the Edit button.
In the empty input box at the bottom of the list, enter the corresponding public key, in the following format:
<protocol> <public-key> username#example.com
This makes your public key automatically available to all of your instances in that project. To add multiple keys, list each key on a new line.
Click Done to save your changes.
It can take several minutes before the key is inserted into the instance. Try connecting with ssh to your instance. If it is successful, your key has been propagated to the instance.

ssh to execute all commands in guest machine

i was created a bash script my_vp.sh that use 2 command:
setterm -cursor off
setterm -powersave off
[...]
#execute video commands
[...]
and is in a computerA
but when i execute it by ssh by another computerB_terminal:
ssh pi#192.168.1.1
execute video commands work correctly in the computerA (the same where is the script)
but the command setterm works in the computerB (the terminal where i execute the ssh command).
somebody can help me with solucione it?
thank you very much!
I am not sure I understood the question:
to execute a local script, but on another machine:
scp /path/to/local/script.bash pi#192.168.1.1:/tmp/copy_of_script.bash
and then, if it's copied correctly, execute it:
ssh pi#192.168.1.1 "chmod +x /tmp/copy_of_script.bash"
ssh pi#192.168.1.1 "bash /tmp/copy_of_script.bash"
to have the remote video (Xwindows, etc) commands appear on the originating machine:
replace : ssh with : ssh -x (to allow X-Forwarding, which will allocate a DISPLAY automatically on the remote machine that will be tunneled back to the originating machine)
for the X-forwarding to work, there are some requirements (usually ok by default, but ymmv) : read more about those requirements in this Unix.se answer

Permission denied to use sftp -b batch file

I can log in to my remote using ssh/sftp (without the -b option)
sftp root#192.168.7.2
But when I try
sftp -b commands.tmp root#192.168.7.2
I get
Permission denied (publickey,password).
Couldn't read packet: Connection reset by peer
Commands.tmp looks like this
ls
exit
Anything I am missing here ?
I used shhpass to write the password no interactive and I needed to add -oBatchMode=no
sshpass -p PASSWORD sftp -v -oBatchMode=no -b FILE USER#SERVER
If you are authentication with a password or an encrypted private key, you cannot use the -b with plain sftp. The sftp man says:
Since it lacks user interaction it should be used in conjunction with non-interactive authentication
You can for example use a passphrase-less private key together with the -b.
If you want to use password authentication, you need to use workarounds like sshpass. See:
How to run the sftp command with a password from Bash script?
This worked for me
sshpass -p 'PASSWORDSTRING' sftp -v -oBatchMode=no -b deploy/production username#ipaddress
production file
put -rp /from-directory /to-directory

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