20090728 Tuesday July 28, 2009

Intstalling Fedora 10 on a Mac Mini

I was on an interview once and the interviewer asked me what kind of Unix I run outside of work. I thought this was an excellent question and one that I often use myself when hiring sysadmins. With few exceptions, the people who are enthusiastic enough to have a machine at home that they can play with and learn from tend to make the best sysadmins.

I responded that I love to run operating systems on "exotic" hardware. I've run OpenBSD on both a Sun IPC and SparcStation 20 (with a 150 MHz Hypersparc processor mind you!) and am currently running it on a Soekris Net4801. I'm also running Fedora on a Mac Mini.

At Terracotta we needed some extra machines for a project I'm working on (very hush, hush :) ), so I decided to drop Fedora 10 on 2 Mac Minis we have that are currently unused. It was not without it's tricks however, even though we have a pretty nice Kickstart setup which configures everything, including Puppet.

Here are the steps:

  1. Boot the Mac from an installer CD and open up the Disk Utility
  2. Partition the drive to have 1 partition and under Options, choose MBR (master boot record)
  3. Install Fedora 10 as normal
  4. Boot up and find out that your machine won't take a DHCP address (arrrgggh!)
  5. sudo yum -y erase NetworkManager
  6. sudo /sbin/chkconfig network on
  7. sudo reboot

For some reason I have yet to understand, the folks at Fedora and many other Linux distributions have this notion that everyone want to run Linux as a desktop. While I do like my Ubuntu desktop (running on a boring PC), I have much more need for servers in my day job. Why Fedora seems to default to a desktop configuration is beyond me. (NetworkManager is for managing a desktop's network configuration). After I turned on networking, everything behaved as normal.

Believe it or not, people actually do run Fedora on servers even though it's very frustrating to have to upgrade every 6 months. Maybe I'm used to it from the OpenBSD release cycle I've been following since OpenBSD 2.5. The reason we use it is at a "cutting edge startup" like Terracotta the developers like to have the latest everything (ruby, svn, etc.) and running on Fedora allows us to provide those things through the regular package management tools (in this case, yum) that come with the system. No need to search all over the Internet for RPMs or build our own, we have enough to do.

Posted by Dave Mangot in Hardware at 20090728

20090330 Monday March 30, 2009

Linksys WET54G, a consumer product?

I recently bought a consumer electronic device that I wanted to hook up to the Internet. This device came with a hard wired Ethernet port, but of course, I had no Ethernet cable where I needed to hook it up and I also had no desire to run one.

There are various devices on the market that can turn a wired Ethernet jack into a wireless one and the one I choose was the Linksys WET54G.

I chose this device for a few reasons:
  1. All my network devices at home are already Linksys
  2. Seemed small and priced no higher than any similar devices
  3. I could get it at my local computer store for the same price as ordering it online

Like most technical folk, I did a lot of reading before purchasing the device. Most of the reviews on Amazon were extremely negative, but I feel like I'm pretty good at sorting through the reviews of the inexperienced vs. the reviews of the knowledgeable. Big mistake! :)

I got the device and learned that because it is version 3.1 of the product, there are no firmware updates available on the Cisco/Linksys website. It is already a newer revision than anything that is even listed. All that was needed was to plug it in and configure it according to the instructions. Here's what happened.
  1. Take the bridge (the WET54G is technically a wireless to Ethernet bridge) and plug it into my Linksys mini-hub. Run the Linksys provided utility on a PC (yeah, I still have an ancient XP box kicking around). Bridge not detected. Power cycle the hub and bridge a few times. Nothing.
  2. Notice that it says the PC and the bridge must be plugged into the same hub. Ohhhh, that must be it. Wire the PC to the hub with a cable. Bridge not detected. Power cycle the hub and bridge a few times, still nothing.
  3. Ok, I figure, how bad could it be to just use the web interface? I look at the docs and supposedly the bridge will autoconfigure at or some weird address like that. Fine, I reconfigure the NIC on the XP machine and soon am on the web interface for the bridge
  4. A few minutes later, the bridge is all configured with ip, netmask, gateway etc. I should be good to go. At this point, my PC says "Duplicate IP detected on the network". Hmmm.
  5. I unplug the PC from the hub and reconfigure everything back to normal (i.e. wireless). The PC is still complaining about duplicate IP and I can no longer ping my default route. Something is fishy.
  6. I plug my media device into the bridge as had been the plan all along, and the device instantly recognizes the network and says it needs a firmware update. Success! I tell it to get the update and it just hangs there, forever.
  7. My wife ways that her PC is saying duplicate device detected as well and she can't get on the Internet. Huh?
  8. Fire up the Mac and I get on the firewall. /var/log/messages tells me that another device on the network is advertising itself as the default route's IP. I check the MAC address and sure enough, it's the bridge!
  9. I get on the web interface for the bridge and change its default route to a bogus address on the network. Why would my bridge need to get out on the Internet anyway? Instantly, all the devices in the house start working correctly.
  10. I configure a static IP address on the media device and it is able to access the Internet without problems. I update its firmware through a USB key anyway.

So now the network is running fine and I haven't had any of the other issues people had described in their reviews. But the question remains: How is this a consumer product? I've designed LANs and WANs for multiple companies. I've configured networks on machine all the way on the other side of the world. I was stumped for a good 20 minutes as to why my network was behaving like it was drunk. What would your average gadgethead have done aside from sit on the phone with Cisco tech support for hours? Would they have figured it out? Crazy.

Update: Yesterday my bridge "lost it's mind" and I will have to reconfigure it from scratch. What a piece of junk. Posted by Dave Mangot in Hardware at 20090330