How to mount a USB drive in Turnkey Linux

I like Turnkey Linux, which is a collection of pre-built server appliances based on Ubuntu. When you need a server fifteen minutes from now, it’s about the only way you can make it happen.

But as far as I can tell, it doesn’t mount USB drives automatically. That’s fine; these servers are designed to have the minimum necessary for their stated purpose in life and nothing more. Here’s how I mount a USB drive to use for making backups.

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How I changed servers midstream

When upgrading this site, I replaced the underlying hardware as well. The old server was just a dead end in too many regards to be worth upgrading in place, and besides, being able to run new and old side by side for a time is helpful.

This type of maneuver is routine work for a professional sysadmin. But it’s been at least two years since I’ve done a similar maneuver at all, and at least five years since I did it with Linux.

When I built the new machine, I gave it a unique IP address. Turnkey Linux makes getting an operational LAMP stack trivial, and depending on what you want to run on that stack, you may even be able to get that installed for you too.

Unfortunately for me, the Geeklog migration tool doesn’t seem to work with WordPress 3.0.1. So I had to get WordPress running on my old hardware in order to migrate. I chose WordPress 2.0.11 because the 2.0 branch appeared to be the current branch when Justdave wrote his migration tool, and 2.0.11 ran without complaint on the dated versions of PHP and MySQL that were on my old server.

After importing the content, I used mysqldump to export my databases. Specifically:

mysqldump --opt -u [mysql username] -p [database name, probably wordpress] > wordpress.sql

I should have gzipped the file, but I didn’t.

gzip wordpress.sql

I then connected to the old server via FTP and transferred the file. Use your favorite file transfer method; I happened to have FTP set up for my internal network.

Uncompress the file if you compressed it:

gunzip wordpress.sql.gz

Then restore the file:

mysql -u [mysql username] -p [database name] < wordpress.sql

Or, if the database already exists, like in my case:

mysqlimport -u [uname] -p [database name] wordpress.sql

Then I connected to the webserver via my web browser. WordPress 3.0.1 saw the WordPress 2.0.11 database and informed me that it needed to be upgraded. So I let it do its thing, and a few minutes later, I had a functioning WordPress site with 10 years’ worth of legacy entries.

I messed around with it for a while. Finally, I decided to go live. And at this point, I should have physically moved the new server into its permanent home. I didn’t do that, so now when I decide to move the server, I’m going to have some downtime.

To flip the IP addresses, you need to know where your Linux box stores its IP address. Debian and Ubuntu both store it in /etc/network/interfaces. As far as I can tell, Red Hat and derivatives like CentOS store it in /etc/sysconfig/network-scripts/ifcfg-eth0, but I haven’t used Red Hat or a derivative in a long time, perhaps 2003.

If worse comes to worse, try something like this to determine where it’s stored:

grep -r [ip address] /etc/

I edited the appropriate file on both boxes, changing the IP address while leaving all of the other parameters unchanged.

I then issued the command ifdown eth0 on both machines.

On my new production server, I then issued the command ifup eth0. Depending on the Linux distribution, it might also be necessary to re-issue a default route command. I didn’t have to do that.

Depending on how much Linux/Unix cred you have at stake, you could just do it the Windows way and reboot the box. Or both of them.

Once I was satisfied everything was working, I powered down the old server and celebrated.

Weekly roundup: 6 Oct 2010

I used to do a weekly roundup every so often, just doing short takes on stuff that interested me as I found it. I haven’t done that in years; I thought I’d give it a whirl again. I don’t know how often I’ll do it, but it was fun.

Ars Technica says Intel’s neutral stance on Atom in servers is a mistake. Absolutely. A dual-core Atom gives plenty of power for infrastructure servers like Active Directory DCs, print servers, and other similar roles. Atoms could even handle many web server tasks.

Xeons are appropriate for database servers and application servers, but throwing them at everything is severe overkill. A lot of server tasks are more disk-bound or network-bound than CPU-bound.

I worked in a datacenter facility for several years that was literally at half capacity, physically. But they didn’t have enough power or cooling capacity to add much more to it.

The only way anything can be added there is to take something away first. Right-sizing servers is the only way to fix that. If they would yank a Xeon, they’d be able to replace it with several Atom-based servers and get a net gain in functionality per square foot and BTU.

Virtualization, a la VMWare, is an option, but one isn’t necessarily a drop-in replacement for the other.

Or, of course, Intel can sit back and wait for ARM to come in and save the day. ARM provides even more functionality per watt. And even though ARM doesn’t run Windows, it does run Linux, and Samba has reached the point where it can stand in for an Active Directory domain controller.

Is there a market out there for a domain controller that fits in a package the size of a CD/DVD drive and consumes less than 20 watts? I’m sure there is. And if Intel doesn’t want to deliver it, ARM and its partners can.

There may be some resistance to ARM, since some decision makers are nervous of things they haven’t heard of, but it should be possible to overcome that. Maybe you haven’t heard of ARM, but guess what? Do you have a smartphone? It has an ARM CPU in it. That PDA you carried before you had a smartphone? It had an ARM CPU in it. It’s entirely possible that your consumer-grade network switch at home has one in it too. Not your router, though. That’s probably MIPS-based. (MIPS is another one of those scary RISC CPU architectures.)

Put a solid operating system on an ARM CPU, and it can run with anything. I have ARM devices that only reboot when the power goes out. If it weren’t for tornado and thunderstorm season causing the power to hiccup, those devices could run for years without a reboot or power-down.

And speaking of ARM, I have seen the future.

Pogoplug is an ARM-based appliance for sharing files. You plug it in, plug USB drives into it, and share files on your home network and the Internet with it. At least, that’s how it’s marketed. But you can hack it into a general purpose Linux box.

Inside, there’s a 1.2 GHz ARM CPU, 256 MB of RAM, and another 256MB of flash memory. Not a supercomputer, but that’s enough power to be useful. And it’s tiny, silent, and sips power. You can plug it in, stash it somewhere, and it’ll never remind you that it’s there.
I’ve actually considered picking up a Pogoplug or two (they go on sale for $45 occasionally, and the slightly less powerful Seagate Dockstar is available for about $30 when you can find them) to run this web site on. Considering how surprisingly well WordPress runs on a 450 MHz Pentium II with 128 MB of RAM (don’t ask me how I know), I think a Pogoplug could handle the workload.

What stops me? I can build an Atom-based PC for less than $150, depending on what I put in it, and run Turnkey Linux on it. Under a worst-case scenario, Turnkey Linux installs in 15 minutes, and it doesn’t take me any longer than that to drop a motherboard and hard drive into a case. So I can knock together an Atom-based webserver in 30 minutes, which is a lot less time than it would take me to get the LAMP stack running on an ARM system.

But if I had more time than money, I’d be all over this.

A device similar to this with an operating LAMP stack on it ready to go is probably too much to ask for. A ready-to-go image running the LAMP stack, similar in form to the DD-WRT or Tomato packages that people use to soup up their routers, might not be. I think it’s a good idea but it isn’t something I have time to head up.

I don’t think I’ve mentioned Turnkey Linux before. I’ve played with it a little, and I’m dead serious that it installs in 15 minutes or less. Installing off a USB flash drive, it might very well install in five.

And it’ll run pretty happily on any PC manufactured this century. More recent is better, of course, but the base requirements are so modest they aren’t worth mentioning.

I’ve built dozens of Linux servers, but this is fantastic. Spend a few minutes downloading an image, copying it onto installation media, and chances are the installation process will take less time than all of that does.

It’s based on Ubuntu LTS, and comes in literally 38 flavors, with more to come after the next refresh is done.

They haven’t built their collection based on the current version of Ubuntu LTS yet because they’ve been distracted with building a backup service. But that’s OK. Ubuntu 8.04.3 still has a little life left in it, and you can either do a distribution upgrade after the initial install, or build a new appliance when the new version comes out and move the data over.

And if Ubuntu isn’t your thing, or you really want 10.04 and you want it now, or worse yet, Linux isn’t your thing, there’s always Bitnami (bitnami.org).

Linux appliances took a little while to get here, but they’re here now, and they work.

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