Continuing my "avoid the console" series, I'm going to cover remotely managing partitions on a Linux server. Yes, this will involve a bit of console, but this will set you on a path to using GUI tools on your servers without having to install a complete windowing environment. Installing a complete desktop-like environment is a waste of resources for most servers, so keeping things to a minimum helps to streamline and allow your servers to do more things with less hardware.

A lot of new Linux users don't realize it, but a Linux desktop has both a "server" and a "client" for drawing things on the screen. This allows you to separate the program's interface from the machine it's running on and display it remotely.

The most powerful way to remotely manage Linux servers is using the SSH (Secure SHell.) It's like a DOS prompt for your server that you can use securely and remotely. The beauty is that if set up properly, it can tunnel a windowed program through that connection to display on your local desktop. Just don't get confused as to what is running where.

For the average joe computer user, if you ask them to "open a console" on their computer they'll stare at you dumbly. For the uninitiated the "console" is the Linux equivalent (loosly) of the "command prompt" or "dos prompt".

So, I just don't understand why it is that a lot of Linux sites and magazines (yes, I'm talking to you, Linux Journal!) insist on forcing the console on everyone for tasks that are just as easy to do without it. Yes, it's nice to know how, and there certainly needs to be a way to find out more about the console, but I firmly believe the console should be reserved for power users and not try to force it on everyone.

Don't get me wrong - I'm not really dissing on Linux Journal. It's a great magazine and it's really targeted more towards the power users like me who will use the console on a daily basis even if you show us a GUI (Graphical User Interface - something everyone has been using since before 1995) that is 10x faster for most people. It's just that the Linux Journal articles recently got me thinking about Linux broadscale desktop adoption.

Perspective

I suddenly found myself needing a separate TFTP boot system for various devices on my network. We utilize a TFTP / PXEBoot installation system for deploying computers.

We also use Vo/IP phones. Mostly the Vo/IP phones are on their own physical network, but there's a few places that isn't practical, so those phones are connected to the regular network. For easy deployment of phones, we provide all of their settings with a combination of a web service and a TFTP configuration pointer from DHCP. That conflicts with the other TFTP settings for desktops.

After a bit of research, I finally figured out how to provide a separate DHCP group within our subnet based on a partial MAC address match - allowing me to choose the phone vendor's MAC prefix as a filter for those devices.

Here's an example file:

ddns-update-style none;
default-lease-time 432000;
max-lease-time 432000;
authoritative;
log-facility local7;

class "phones" {
        match if binary-to-ascii(16,8,":",substring(hardware,0,4)) = "1:0:4:13";
}

class "other" {
        match if not(binary-to-ascii(16,8,":",substring(hardware,0,4)) = "1:0:4:13");
}

# subnet
subnet 192.168.1.0 netmask 255.255.255.0 {
        option routers 192.168.1.254;
        option domain-name-servers 192.168.1.8, 192.168.1.9;
        pool {
                range dynamic-bootp 192.168.1.150 192.168.1.199;

I run Google Analytics on my nook-look.com nook screensaver and wallpaper site. Here's a few interesting tidbits that some of you other geeks might be interested in.

The average time spent on the site is 10 minutes.
The average user views around 20 pages each visit.
40% of my traffic is from bookmarks.
31% of users run Firefox.
28% run IE.
15% are actually browsing from their nook!
13% are using a Mac. Yeah, nook beats you ;-)

18 visitors this month used a Blackberry. Why?

Google Search provides 85% of incoming search traffic.
Yahoo is in second place with 6% of incoming search traffic.
Bing provided less than 5%. Think about that for a minute.
Ask.com brought 40 visitors this month. And when you consider I'm in second place right behind B&N when you search ask.com for "nook screensavers"... Yeah. Not a lot of market share for "the algorithm," at least among nook users.

Why bother with a locked-in iPad if you're a true technohead, when you can install Ubuntu on the Archos 9 Internet Tablet? The Archos 9 has several flaws, mostly surrounding the installed software. People say it's slow, but really with something other than "Windows Starter" it's actually pretty peppy. The internal hard drive is a bit slow, so I replaced mine with an SSD so I don't have to worry about a physically spinning drive anymore in my hands, and I get better performance.

Installing Ubuntu on it isn't for the weak kneed, but it's not that tough either. Here's a step by step to get you up and running.

I stumbled on a little bug today while trying to use my Sennheiser USB headset adapter with my Sennheiser headphones. I plugged them in and got nothing...

The device would appear in System - Preferences - Sound, but on the available output tab it didn't show.

A bit more probing found that Alsa worked just fine with it.

Finally I determined that Pulseaudio wouldn't fully recognize the headset after it was plugged in until it was restarted. To do this you can either log out and log back in or type in the following commands at a console:

pulseaudio -k
pulseaudio --check

Be sure you don't have any software open that's using the speakers or mic at the time or that program will likely freeze up.

Anyone else see anything wrong with this screenshot?

Yeah, weird, huh? For some reason it was reporting my disk usage as a NEGATIVE number. I've never seen that before. I found it because ZoneMinder had stopped recording for some reason - it thought I was out of hard disk space when in actuality there's very little drive used. A quick reboot fixed the problem. Lucky for me there's nothing important on this box - it's simply for zoneminder and watching Hulu or streaming my MythTV recordings to my bedroom. I think this happened after our power spike and outage the other day. This particular PC isn't on a UPS.

Well, it seems they still haven't made any progress at making the Compiz graphics effects work on a multi-GPU setup, but you can run two X screens each using two monitors and keep the Compiz effects. If you want to grab and drag windows across all four monitors, you lose the cool graphics effects.

Here's what it might look like though using four monitors of three different sizes using xinerama without Compiz on Ubuntu Lucid 10.04 with two nVidia cards, each driving two monitors:

I decided it was time to place a PXE boot install image on my network for installing Ubuntu 10.04 Lucid desktops. For the most part everything went as expected (see this post) but during the install I got an error that "restricted/binary-amd64/Packages was corrupt".

It turns out there are no restricted packages on the alternate installer image, and the lack of an empty "Packages" file at "/dists/lucid/restricted/binary-amd64" where the networked install image is located was causing it to bomb.

Simply doing

touch Packages

in that shared directory within the install image seems to have fixed the issue. For some reason the fact that the Packages.gz ungzips into a zero byte file was throwing it, but having an already existing zero byte file seemed to fix it.

I just did a security patch upgrade on an Ubuntu Karmic server. I know, Lucid is out but I'm not ready to jump on that bandwagon with any more servers yet.

Immediately after the upgrade, I noticed that SSH logins took literally forever and were followed by:

timeout in locking authority file: .Xauthority

It turns out that something with this latest upgrade caused my home directory to not be writable by... me. This was definitely not a problem before the upgrade. I'm assuming it will only affect those using encrypted home directories.

Quick fix: after logging in as myself, I did:

sudo chmod u+w /home/[yourdirectory]

It didn't have to be done recursively because all of the subdirectories had retained their permissions.