Eleven SSH Tricks
If you connect from one server to another using public key authentication, you don't need to run an authentication agent on both. SSH automatically can pass any authentication requests coming from other servers, back to the agent running on your own computer. This way, it never passes your secret key to the remote computer; rather, it performs authentication on your computer and sends the results back to the remote computer.
To set up authentication agent forwarding, simply run ssh -A or add the following line to your config file:
You should use authentication agent forwarding only if you trust the administrators of the remote computer; you risk them using your keys as if they were you. Otherwise, it is quite secure.
Many people carry a floppy with PuTTY or another Windows SSH program, in case they need to use an unsecured computer while traveling. This method works if you have the ability to run programs from the floppy drive. You also can download PuTTY from the web site and run it.
Another alternative is putting an SSH Java applet on a web page that you can use from a browser. An excellent Java SSH client is Mindterm, which is free for noncommercial use. You can find it at www.appgate.com/mindterm.
An SSH configuration can go wrong in a few places if you are using these various tricks. You can catch many problems by using ssh -v and watching the output. Of course, none of these tricks is essential to using SSH. Eventually, though, you may encounter situations where you're glad you know them. So give a few of them a try.
Daniel R. Allen (firstname.lastname@example.org) discovered UNIX courtesy of a 1,200-baud modem, a free local dial-up and a guest account at MIT, back when those things existed. He has been an enthusiastic Linux user since 1995. He is president of Prescient Code Solutions, a software consulting company in Kitchener, Ontario and Ithaca, New York.
|Designing Electronics with Linux||May 22, 2013|
|Dynamic DNS—an Object Lesson in Problem Solving||May 21, 2013|
|Using Salt Stack and Vagrant for Drupal Development||May 20, 2013|
|Making Linux and Android Get Along (It's Not as Hard as It Sounds)||May 16, 2013|
|Drupal Is a Framework: Why Everyone Needs to Understand This||May 15, 2013|
|Home, My Backup Data Center||May 13, 2013|
- Designing Electronics with Linux
- Making Linux and Android Get Along (It's Not as Hard as It Sounds)
- Dynamic DNS—an Object Lesson in Problem Solving
- New Products
- Using Salt Stack and Vagrant for Drupal Development
- Validate an E-Mail Address with PHP, the Right Way
- Build a Skype Server for Your Home Phone System
- Why Python?
- Tech Tip: Really Simple HTTP Server with Python
- A Topic for Discussion - Open Source Feature-Richness?
- Not free anymore
59 min 37 sec ago
4 hours 46 min ago
- Reply to comment | Linux Journal
4 hours 54 min ago
- Understanding the Linux Kernel
7 hours 9 min ago
9 hours 39 min ago
- Kernel Problem
19 hours 42 min ago
- BASH script to log IPs on public web server
1 day 9 min ago
1 day 3 hours ago
- Reply to comment | Linux Journal
1 day 4 hours ago
- All the articles you talked
1 day 6 hours ago
Enter to Win an Adafruit Pi Cobbler Breakout Kit for Raspberry Pi
It's Raspberry Pi month at Linux Journal. Each week in May, Adafruit will be giving away a Pi-related prize to a lucky, randomly drawn LJ reader. Winners will be announced weekly.
Fill out the fields below to enter to win this week's prize-- a Pi Cobbler Breakout Kit for Raspberry Pi.
Congratulations to our winners so far:
- 5-8-13, Pi Starter Pack: Jack Davis
- 5-15-13, Pi Model B 512MB RAM: Patrick Dunn
- 5-21-13, Prototyping Pi Plate Kit: Philip Kirby
- Next winner announced on 5-27-13!
Free Webinar: Hadoop
How to Build an Optimal Hadoop Cluster to Store and Maintain Unlimited Amounts of Data Using Microservers
Realizing the promise of Apache® Hadoop® requires the effective deployment of compute, memory, storage and networking to achieve optimal results. With its flexibility and multitude of options, it is easy to over or under provision the server infrastructure, resulting in poor performance and high TCO. Join us for an in depth, technical discussion with industry experts from leading Hadoop and server companies who will provide insights into the key considerations for designing and deploying an optimal Hadoop cluster.
Some of key questions to be discussed are:
- What is the “typical” Hadoop cluster and what should be installed on the different machine types?
- Why should you consider the typical workload patterns when making your hardware decisions?
- Are all microservers created equal for Hadoop deployments?
- How do I plan for expansion if I require more compute, memory, storage or networking?