How do you run a program on a remote server using ssh?
For this example we'll have two servers, one named Johnny and another named Cash. Both are running openssh. Our goal is to have a program on Johnny login to Cash and run a program on Cash. To make the task a little more complex we'll be using different users on each machine.
The first thing we'll need to do is generate public and private keys on Johnny. So, logged into Johnny as user 'boy' we create public and private keys by creating them in the .ssh directory as follows:
Johnny$> pwd
/home/boy/.ssh
Johnny$> ssh-keygen -t rsa -f sue
Generating public/private rsa key pair.
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in sue.
Your public key has been saved in sue.pub.
The key fingerprint is:
8d:e9:c0:g1:c7:1f:e3:b3:2f:38:12:aa:b5:3b:2e:b3 boy@Johnny
Johnny$>
In the example above we picked an arbitrary name, sue, to identify the files that hold the generated keys. When prompted to enter a passphrase (twice) we simply hit enter twice.
As the output of ssh-keygen indicates, the public key has been saved in a file named sue.pub.
The output of ssh-keygen implies, but doesn't indicate directly, that the private key is in a file named sue (Yes, a user named boy created a file named sue.)
Johnny$>ls -l
-rwx------ 1 sue suegrp 887 Oct 17 14:27 sue
-rwx------ 1 sue suegrp 223 Oct 17 14:27 sue.pub
The private key file, sue, will remain on Johnny for the reaminder of this exercise, but the public key must be moved to the remote server, Cash. Note that the .ssh directory itself, as well as the sue and sue.pub files should have permissions of 700.
Now you'll need to ftp the sue.pub file from Johnny to Cash. The user on Cash that we'll login as is user 'named'.
Johnny$> ftp Cash
Connected to Cash
220 Cash - Propery of Xyz. - Authorized users only
Name (Cash:boy): named
331 Password required for named.
Password:
230-Last unsuccessful login: Fri Oct 17 13:12:55 2003 on ftp from Johnny 230-Last login: Fri Oct 17 16:02:11 2003 on /dev/pts/1 from Johnny
230 User named logged in.
ftp> cd .ssh
ftp> mput sue.pub
mput sue.pub? y
200 PORT command successful.
150 Opening data connection for sue.pub.
226 Transfer complete.
224 bytes sent in 0.000781 seconds (280.1 Kbytes/s)
local: sue.pub remote: sue.pub
ftp>bye
221 Goodbye.
Johnny$>
Now we'll telnet into Cash and concatenate the sue.pub file into /home/named/.ssh/authorized_keys file.
Cash$> pwd
/home/named/.ssh
Cash$> cat sue.pub >> authorized_keys
Cash$> exit
Connection closed.
Johnny$>
Let's recap what we've done so far.
1) We've created public and private keys on Johnny.
2) We've ftp'd the public key file, sue.pub, from Johnny to Cash.
3) We've telnetted to Cash, and concatenated the contents of sue.pub into authorized_keys
We're now ready to manually login from Johnny to Cash using ssh.
Johnny$> ssh -i /home/boy/.ssh/sue named@Cash
The authenticity of host 'Cash (xxx.yyy.zzz.aaa)' can't be established.
RSA key fingerprint is 65:11:7d:ef:ed:a3:cc:34:d1:b5:ba:c9:16:22:31:23.
Are you sure you want to continue connecting (yes/no)? yes
================================================================
*** NOTICE TO ALL USERS ***
================================================================
Cash$>exit<
/p>
Connection to Cash closed.
Johnny$>
Now on Johnny, create a shell script called 'boynamedsue.sh' with the following one line of contents and chmod the script to 777.
ssh -i /home/boy/.ssh/sue named@Cash /usr/bin/ls -l
Next, execute the script on Johnny.
Johnny$> boynamedsue.sh
================================================================
*** NOTICE TO ALL USERS ***
================================================================
-rwxrwxr-x 1 named namedgrp 10020 Oct 17 14:35 namedfile1.txt
-rw-r--r-- 1 named namedgrp 680 Aug 14 16:18 namedfile.html
-rw------- 1 named namedgrp 1148 Aug 18 09:51 mbox
drwxr-xr-x 2 named namedgrp 512 Jun 17 13:38 old
Johnny$>
You just executed a program on Johnny, that logged into Cash and ran a program (unix 'ls -l').
The next step you'll want to take is to replace the '/usr/bin/ls -l' command in the boynamedsue.sh program with the path and name of the program that you want to run.
About The Author
C.S. Deam is a small business owner. His eBook Computer Nuggets: Non-Techie Internet Tips For In-Laws, Out-Laws, and the Rest of Society is a great gift for non-techie family members and is available at www.linkertonpublishing.com where you can sign up for FREE E-Courses & Newsletters to help you on your path to self-employment.
Alto Pass chicago limos ..Heard about the Quark "killer"?Adobe InDesign CS2. Will it really... Read More
XML parser is a software module to read documents and... Read More
Most computer users use spreadsheets software such as Microsoft Excel... Read More
Microsoft Business Solutions Great Plains was purchased from Great Plains... Read More
If you would like to pick something from Microsoft, or... Read More
Mike Dunville* had a decision to make. As the new... Read More
Your computer cost you from hundreds to thousands of dollars,... Read More
Did you ever give a thought to the number of... Read More
Siebel is traditional CRM market leader, however and mostly due... Read More
Every organization which creates collaborative documents, whether they are budgets,... Read More
When making a decision to buy any piece of software... Read More
The intuitive algorithm.Roger Penrose considered it impossible. Thinking could never... Read More
Are you one of those people that keeps track of... Read More
Did you ever want to erase everything on your computer?... Read More
GroupwareThe internet is full of 1.5 million to 7 million... Read More
I love new technology. I am still ready to wait... Read More
Microsoft Great Plains is main Microsoft Business Solutions accounting package... Read More
Microsoft Great Plains, Navision, Solomon and Axapta are Microsoft Business... Read More
ERP (Enterprise Resource Planning) Overview covers What is ERP, Brief... Read More
Microsoft Business Solutions Great Plains serves to the wide spectrum... Read More
I like my software simple. If it's too complex or... Read More
Research bears that less than 70 percent of development projects... Read More
The cornerstone of successful automated office systems is the ability... Read More
TikiWiki is open source software - it is written in... Read More
Microsoft Client Relation Management system (Microsoft CRM) and Microsoft RMS... Read More
Alto Pass cool limo ..There are many commands that are used in linux on... Read More
Remember back in the days where screensavers were the coolest... Read More
How to delete the user? This is the first problem... Read More
For a windows user like me, just can watch with... Read More
What is Groupware?Have you ever had to manage document collaboration... Read More
This short paper will expand on two key reasons to... Read More
A LOT OF UNWANTED FILES.When you uninstall an item of... Read More
In order to implement VLANs in a network environment, you'll... Read More
Microsoft Great Plains might be considered as ERP platform to... Read More
ERP Consulting industry is on the way to serve clients... Read More
Microsoft Great Plains ? ERM from Microsoft Business Solutions and... Read More
Spyware is software or hardware installed on a computer without... Read More
Having from five to ten and more favorite screensavers is... Read More
Lotus Domino/Notes ? Microsoft Great Plains tandem as ERP with... Read More
Are you a whiz at calculating financial information? Not the... Read More
So let's begin crunching down these 300 images using Adobe... Read More
And kill the best layout software in the process of... Read More
The Windows Indexing Service provides you with the ability to... Read More
The title of "software engineer" has got to be among... Read More
How do you run a program on a remote server... Read More
Microsoft Business Solutions products: Great Plains, MS CRM, Navision, Axapta,... Read More
Features Additionally, Vista will include many other new features.Aero Vista... Read More
Are Spreadsheets Robbing your Enterprise of Competitive Advantage?'90% of "average"... Read More
In today's business world it's all but impossible to escape... Read More
A few months back I really got sick of my... Read More
Software |