Penguins-On-Hudson is an advocacy program sponsored by Codefix Consulting to help promote Linux and F.O.S.S. (Free Open Source Software) in the lower Hudson River Valley.
In most cases, Ubuntu desktop systems will automatically detect and mount removable media, and this is largely done with software that is part of the X Windows system; for server systems without X Windows however, this sort of thing requires a bit of work.
Now some may ask, “Why automount removable media at all?” It is […]
Sound problems fall in to three basic categories, and the first thing you want to do is determine which one you’re dealing with. The easiest thing you can do is test your speakers with something else, using the same cable. If your speakers and cable are confirmed to be in good working order, then the […]
prerequisite concepts: prelude, basic configuration, port forwarding
Network address translation (NAT) is a very common method of providing secure access to hosts on a private network. Given the limited amount of IPv4 addresses, computer networks with relatively few, very few, and even a single public IP address are common. A typical small business customer of […]
prerequisite concepts: prelude, basic configuration
Port forwarding is a versatile feature which informs several popular concepts, including X Forwarding and tunneling which are briefly explained below; more advanced port magic will be addressed elsewhere.
X Forwarding
At the end of the previous installment of this series is an example SSH client configuration file, usually located at ~/.ssh/conf; […]
prerequisite concepts: prelude
If you’re not already using a config file (~/.ssh/config) you should peruse the documentation to see what it offers; an ongoing benefit I enjoy is that it allows me to accomplish more while typing less. Suppose, for example, you need to access two mail servers which are both behind a firewall and sharing […]
This is a prelude to a series of articles focused on how the sophisticated power of OpenSSH may be harnessed to great advantage with less effort than one might think. Readers already familiar with OpenSSH and passwordless authentication may wish to skip ahead:
OpenSSH: Basic Configuration
OpenSSH: Port Forwarding
OpenSSH: Proxy Connections
OpenSSH: Environmental Override
SSH Coolness … Even On […]
AppArmor, introduced to Ubuntu with Gutsy, is yet another security tool unleashed upon the infosphere. In part, AppArmor is intended as an alternative to SELinux, which can easily be seen as daunting to configure; unfortunately, many such projects are daunting for those admins forced to walk the plank of unfamiliarity above a sea of expectations. […]
Shortly after I last upgraded my mail server, one user reported that his mail client was failing to connect with the message:
“Unable to connect to your IMAP server. You may have exceeded the maximum number of connections to this server…”
He was the only one known to be having this issue, so after a cursory check […]
I have resisted the urge to display caller id on my MythTV as somewhat obvious. I’m always looking for ways to demonstrate the freedom which comes from using open source software, but I prefer the zesty freshness of an original idea rather than anything that’s been done, redone, and done again. My wife, however, […]
When I wrote about building my own PBX, I mentioned that I set up Direct Inward Dialing (DID), a feature which allows virtual phone numbers to be routed directly to extensions while using shared trunks (phone lines). I figured out how to accomplish this after reading this discussion, but made improvements along the way.