08-01-2002
If you need to log in as a user other than the current username on the local side (e.g. you're logged in as penguin, and want to log in to the remote machine as tux, not penguin), specify the username either with the -l (login) option, or username@host format.
$ ssh tux@mouton uname -a
or
$ ssh -l tux mouton uname -a
If you're wanting to run remote commands without entering your password every time, read up on SSH public-key authentication. When you have your public-key auth set up correctly between the two machines, use ssh-agent(1) to store your password locally, and authenticate you to other servers. The ssh-agent program will prompt you only once for your private key passphrase, then do authentication to other machines for you until you kill the ssh-agent process.
If you create your private key without a passphrase (by pressing Enter when prompted for passphrase), it will be unencrypted and you will never need to input a passphrase to decrypt your private key for authentication. I do not recommend this method when it can be avoided, for the obvious security reasons (if someone obtains access to the file, it is unprotected and they will be able to authenticate as you to other machines).
9 More Discussions You Might Find Interesting
1. Cybersecurity
Eh... yeah. What the title says. :D (1 Reply)
Discussion started by: PSC
1 Replies
2. Shell Programming and Scripting
I am using Net::SSH::Expect to connect to the device(iLO) with SSH. After the $ssh->login() I'm able to view the prompt, but not able to send any coommands.
With the putty I can connect to the device and execute the commands without any issues.
Here is the sample script
my $ssh =... (0 Replies)
Discussion started by: hansini
0 Replies
3. Shell Programming and Scripting
Hi,
I want to use ssh to add a register key on remote ssh server. Since there are space characters in my register key string, it always failed. If there is no space characters in the string, it worked fine. The following is what I have tried. It seems that "ssh" command doesn't care about double... (9 Replies)
Discussion started by: leaftree
9 Replies
4. UNIX for Dummies Questions & Answers
This issue was resolved due to using the correct user transferring the file over to the desktop. (1 Reply)
Discussion started by: Computergal2104
1 Replies
5. Shell Programming and Scripting
I have write a script which contains
ssh -p 12345 dcplatform@10.125.42.50
ssh 127.0.0.1 -p 5555 "$CMD"
ssh root@$GUEST_IP "$CMD"
before I use public key, it works well, now I want to change to "expect", BUT I don't want to change above code and "parameter position"
I can post a... (1 Reply)
Discussion started by: yanglei_fage
1 Replies
6. UNIX for Dummies Questions & Answers
I'm trying to setup a link between my home pc (work-machine) and a server at work (tar-machine) that is behind a gateway (hop-machine) and not directly accessible.
my actions:
work-machine$ ssh -L 1234:tar-machine:22 hop-machine
work-machine$ ssh -p 1234 user@127.0.0.1
- shh access on... (1 Reply)
Discussion started by: Vathau
1 Replies
7. Shell Programming and Scripting
I'm using redhat and have an odd issue with a nested ssh call.
ssh -i ~/.ssh/transfer-key -q transfer@fserver1 ]
&& ssh -i ~/.ssh/transfer-key transfer@fserver1 "ssh -i ~/.ssh/sftp-key sftpin@10.0.0.1 ]"
&& ssh -i ~/.ssh/transfer-key transfer@fserver1 "scp -i ~/.ssh/sftp-key /home/S/outbox/*... (2 Replies)
Discussion started by: say170
2 Replies
8. UNIX for Beginners Questions & Answers
Hi,
I want to validate ssh connection one after one for multiple servers..... password less keys already setup but now i want to validate if ssh is working fine or not...
I have .sh script like below and i have servers.txt contains all the list of servers
#/bin/bash
for host in $(cat... (3 Replies)
Discussion started by: sreeram4
3 Replies
9. Shell Programming and Scripting
Hi,
I am trying to complete my bash script in order to find which SSH servers on LAN are still active with the ssh keys, but i am frozen at this step:
#!/bin/bash
# LAN SSH KEYS DISCOVERY SCRIPT
</etc/passwd \
grep /bin/bash |
cut -d: -f6 |
sudo xargs -i -- sh -c '
&& cat... (11 Replies)
Discussion started by: syrius
11 Replies
LEARN ABOUT LINUX
ssh-add
SSH-ADD(1) BSD General Commands Manual SSH-ADD(1)
NAME
ssh-add -- adds private key identities to the authentication agent
SYNOPSIS
ssh-add [-cDdLlXx] [-t life] [file ...]
ssh-add -s pkcs11
ssh-add -e pkcs11
DESCRIPTION
ssh-add adds private key identities to the authentication agent, ssh-agent(1). When run without arguments, it adds the files ~/.ssh/id_rsa,
~/.ssh/id_dsa, ~/.ssh/id_ecdsa and ~/.ssh/identity. After loading a private key, ssh-add will try to load corresponding certificate informa-
tion from the filename obtained by appending -cert.pub to the name of the private key file. Alternative file names can be given on the com-
mand line.
If any file requires a passphrase, ssh-add asks for the passphrase from the user. The passphrase is read from the user's tty. ssh-add
retries the last passphrase if multiple identity files are given.
The authentication agent must be running and the SSH_AUTH_SOCK environment variable must contain the name of its socket for ssh-add to work.
Any keys recorded in the blacklist of known-compromised keys (see ssh-vulnkey(1)) will be refused.
The options are as follows:
-c Indicates that added identities should be subject to confirmation before being used for authentication. Confirmation is performed by
the SSH_ASKPASS program mentioned below. Successful confirmation is signaled by a zero exit status from the SSH_ASKPASS program,
rather than text entered into the requester.
-D Deletes all identities from the agent.
-d Instead of adding identities, removes identities from the agent. If ssh-add has been run without arguments, the keys for the default
identities will be removed. Otherwise, the argument list will be interpreted as a list of paths to public key files and matching
keys will be removed from the agent. If no public key is found at a given path, ssh-add will append .pub and retry.
-e pkcs11
Remove keys provided by the PKCS#11 shared library pkcs11.
-L Lists public key parameters of all identities currently represented by the agent.
-l Lists fingerprints of all identities currently represented by the agent.
-s pkcs11
Add keys provided by the PKCS#11 shared library pkcs11.
-t life
Set a maximum lifetime when adding identities to an agent. The lifetime may be specified in seconds or in a time format specified in
sshd_config(5).
-X Unlock the agent.
-x Lock the agent with a password.
ENVIRONMENT
DISPLAY and SSH_ASKPASS
If ssh-add needs a passphrase, it will read the passphrase from the current terminal if it was run from a terminal. If ssh-add does
not have a terminal associated with it but DISPLAY and SSH_ASKPASS are set, it will execute the program specified by SSH_ASKPASS and
open an X11 window to read the passphrase. This is particularly useful when calling ssh-add from a .xsession or related script.
(Note that on some machines it may be necessary to redirect the input from /dev/null to make this work.)
SSH_AUTH_SOCK
Identifies the path of a UNIX-domain socket used to communicate with the agent.
FILES
~/.ssh/identity
Contains the protocol version 1 RSA authentication identity of the user.
~/.ssh/id_dsa
Contains the protocol version 2 DSA authentication identity of the user.
~/.ssh/id_ecdsa
Contains the protocol version 2 ECDSA authentication identity of the user.
~/.ssh/id_rsa
Contains the protocol version 2 RSA authentication identity of the user.
Identity files should not be readable by anyone but the user. Note that ssh-add ignores identity files if they are accessible by others.
EXIT STATUS
Exit status is 0 on success, 1 if the specified command fails, and 2 if ssh-add is unable to contact the authentication agent.
SEE ALSO
ssh(1), ssh-agent(1), ssh-keygen(1), ssh-vulnkey(1), sshd(8)
AUTHORS
OpenSSH is a derivative of the original and free ssh 1.2.12 release by Tatu Ylonen. Aaron Campbell, Bob Beck, Markus Friedl, Niels Provos,
Theo de Raadt and Dug Song removed many bugs, re-added newer features and created OpenSSH. Markus Friedl contributed the support for SSH
protocol versions 1.5 and 2.0.
BSD
October 28, 2010 BSD