Phishing attempt via TXT
Posted by BryanM in Business, Technology on July 24, 2009
Hey everyone, I was going to post this yesterday, but my internet was on the fritz. On Wednesday while at dinner I received a text message telling me to call a number to activate my credit card, I knew right away this was a phishing attempt. After dinner, I went to the Verizon store right around the corner to see if they had a number for reporting these kinds of things. Read the rest of this entry »
5 Tips On Being An Effective Linux Admin
Posted by AndrewL in Technology on July 21, 2009
Earlier this week someone did something very bad, and it got me thinking about what are some of the simple things that make someone an effective Linux admin. While I will not tell you that following my advice will make you some kind of super-admin, it will help you when dealing with Linux servers and hopefully save you and others from needless headaches. Here are my tips on being an effective Linux admin, in no particular order. Read the rest of this entry »
Windows 7: The Top 5 Things I like
Posted by BryanM in Technology on July 6, 2009
I have been running Windows 7 as my primary and only OS on my desktop and laptop for several months. I have no plans of going back to XP. This OS is rock-solid stable and fast. Great hardware support and new features and enhancements on old features make it by far the most attractive OS on the horizon, as far as I am concerned. I am, without a doubt, planning to purchase Windows 7 Ultimate when it releases, too bad it is not available for half off preorder. Here are my own top 5 reasons why Windows 7 is awesome. Read the rest of this entry »
FAIL: Why you should ALWAYS use visudo
Posted by AndrewL in Technology on July 6, 2009
It’s time for a short rant about proper Linux administration. Someone, who shall not be named, manually edited the /etc/sudoers file and broke it on a critical server. In case you don’t know, on Linux sudo allows you to run commands as the root (Administrator) user, and the sudoers file determines who can use sudo and what they can do with it. Read the rest of this entry »
Firefox 3.5: Impatiently Waiting
Posted by AndrewL in Technology, Tutorials on July 1, 2009
In case you have been living under a rock, Firefox 3.5 came out today (well technically yesterday). I’ve noticed a lot of people wondering how they can get it running smoothly on Ubuntu. Never fear, after much trial and error (a lot of error) I’ve found what I think should be the easiest way to install the latest version of Firefox. So if you are just as impatient as I am, you can rejoice in the all the cool new features. Read the rest of this entry »
Tweaking Nagios For Performance
Posted by AndrewL in Technology, Tutorials on April 19, 2009
The company I work for has about 3,000 servers that need to be monitored in our Dallas datacenter. For the past few years we’ve been using a fairly standard Nagios setup. If you don’t take the time to really learn Nagios and tweak the config files it’ll run fairly well, until you are monitoring more then a few hundred servers. The reason that Nagios slows down when checking 300+ servers is that it stores all state/check information in a flat text file on the system’s hard drive. When you have only a few servers and services to check it’s not so bad, but when you the more you add, the more IOPS you’ll see. At 3,000 servers disk IO is a huge bottleneck.
A lot of systems will be fairly responsive but show a really high load average, this is because of IO wait. Fortunately, the guy who setup Nagios at our DC was smart enough to realize we had a massive issue with disk IO and so he had everything running off 4x 15k RPM SCSI drives with a hardware RAID 10. Unfortunately, even with the fairly substantial hardware Nagios still took nearly 20 minutes to check every system in the datacenter. For a while, this was considered acceptable, because we didn’t want to pay thousands of dollars for a commercial system and this particular admin was convinced that Nagios was running as fast as possible for now and that maybe the Nagios developers would speed things up in a later version.
Cooling Off
Posted by AndrewL in Technology on April 14, 2009
I’ve been running Ubuntu 9.04 beta on my desktop at home for a few weeks now, so I decided it was time to upgrade my laptop. I hoped that by upgrading, I’d be able to signifigantly reduce the time it took for my laptop to boot up. Unfortunetly, disaster stuck halfway through. My laptop overheated and locked up, leaving me with half new and half old packages. Needless to say, it did not come back online very easily. I managed to get it to a point where I could copy my data off to another computer, then I did a fresh install of Ubuntu.
What an ugly heatsink.
I was prepared this time though, I decided I needed a way to insure my laptop will stay cool. I grabbed a dead LaCie external hard drive (one of the spares from The Monster) and set my laptop on it. These things are HEAVY, the outer case of the drive is made of a pretty solid metal (possibly steel, it feels too heavy to be aluminum) and it works great as a makeshift heatsink.
As you can see, it’s not the nicest looking heatsink, but it’ll have to do until I can fix the overheating problem. On the plus side, Ubuntu 9.04 is running great. The laptop boots up much faster then before and I love the new “Dust” theme. It’s the first dark colored theme for Gnome that I’ve found to actually work well, it’s also fairly compact which is great since the laptop has a small screen.
I swear the blurred out bookmarks are work-related, not porn.
Tomorrow I plan on posting a tutorial on how to I tweaked my Nagios setup at work to monitor 3000 servers every 3 minutes.
Birth of a Monster
Posted by AndrewL in Technology on April 8, 2009
Sometimes I like to stay late at work, I’ve got a nice desk, a decent computer, and a mini-fridge full of drinks right behind me. So even after I’m off work, I sometimes stay up here and work on side projects or just browse the web. Yesterday, I decided to do something a bit more creative, I decided to build a monster.
We recently came into the possession of several LaCie external hard drives. Most of these are 1.6TB and can use firewire or USB to connect to a computer. The downside to these drives, is that they aren’t actually one single drive, each one is an enclosure with 4 IDE drives inside it setup to use JBOD or something similar to RAID 0. If even one of those drives dies, the entire LaCie is lost. Needless to say, we don’t have a lot of use for what amounts to a giant hard drive with a death wish.
So I figured, lets see how many I can hook up to one system, then software raid them and see how fast they are. I had a dual 2.4Ghz XEON box laying around, so I threw in a bunch of firewire cards. I had to remove the entire back of the case just to fit the cards, otherwise we wouldn’t be able to use the card on the far left or the far right.
This server is stuffed full of firewire cards.
As you can see, I also had to remove the back panel of the firewire cards, since I didn’t have any half height ones to use. All in all, it makes for quite an ugly setup. Here’s the front and back of the entire thing:
I use only the best of out-dated equipment.
This is actually fairly clean compared to some of the co-located servers our customers have setup.
As of right now I’ve got mdadm (the Linux software raid utility) building a RAID 6 out of the 1.6TB drives. When I first started building the array I was given an ETA of 1,500 minutes. For those of you that can’t do the math in your head (I can’t), that’s 25 hours! Right now it’s at about 80% complete. I’ll update this article sometime tomorrow, after I’ve got the array formatted for ext3, which will probably take quite awhile.
UPDATE:
The raid finally finished building, in total it took just under 24 hours, it took another 45 minutes to format the partition to ext3. I ran a quick test with hdparm to see how fast the array was, the individual drives are capable of about 70MBps and the array as a whole clocks in at around 150MBps. Not great, but not too bad either, the real test will be seeing how long the array stays online, since the LaCie drives aren’t exactly the most robust storage devices.
Terrorists Don't Use Google Maps
A while back, we got an e-mail from a customer who was concerned that terrorists might be using her site to plan an attack on the space shuttle. Please note, this is a real ticket that was submitted to our security department by one of our customers. Identifying information has been removed and replaced with asterisks (*). See the entire story after the jump. Read the rest of this entry »
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