Direction determines speed

See if this makes sense to you.  I was driving to a client’s house yesterday to fix a computer. As soon as I turned on one of the roads, there was a speed limit sign showing 35 (north bound traffic).  Almost a mile after passing that sign, another speed limit sign is on the other side of the road showing 45 mph (south bound traffic).  There was no sign on the northbound side showing 45 mph.

What the hell?  I wonder if anyone on the south bound side has ever been pulled over by a cop sitting on the north bound side for speeding even though they were going 45?  I played it safe and took a different road home (one that has the same speed limit on both sides).

Before I forget: Happy New Year!

If you break your neck, if you have nothing to eat, if your house is on fire, then you got a problem. Everything else is inconvenience. – Robert Fulghum

01.Jan.09 General Comment (1)

Watch the dot

You have to be careful when typing commands.  One character out of place can cause strange problems or even total break down.  So is the case of a recent SQL backup scheme.

One of the other DBA’s I work with had a problem.  They were trying to run full backups of a live database but the backup drive kept filling up.  The reason it would fill up was because the old backup files (*.bak) were not being deleted when the next backup ran.  One backup file takes up 20+ gigabytes of space (heavily used database).  My coworker had tried different commands to make it work but nothing was fixing the issue.

I opened up SQL Server Management Studio and took a look at the Maintenance Plan being used.  The maintenance plan had two subplans.  The first subplan made a full backup of the database at 3 a.m. every day.  The second subplan made a transaction log backup every two hours.  I opened up the first subplan in order to review the tasks.

Everything looked normal at first.  When I opened up the first task in order to view the details, I saw the problem.  The first task, a maintenance cleanup task, is the one set to delete old backup files.  My coworker had set it to search the backup folder for the .bak extension.  The problem is that you can’t add the dot before the file extension to be found.  I removed the period, saved the subplan and launced the full backup job.  We knew it was working when it immediately deleted the old backup files and then created the new backup.

One other piece of advice I gave him about the backups was the frequency.  This database is used about 18 hours a day.  Currently, a database failure at 2 a.m. would lose a full days worth of data.  I suggested that he perform differential backups at least every 2 hours and leave the full backup as it was.  We did the calculations for the drive space needed and found that he had more than enough room for running differential backups every hour if he wanted.  That will definitely help to keep Murphy at bay.

I don’t know the key to success, but the key to failure is trying to please everybody. – Bill Cosby

22.Dec.08 Microsoft SQL Comments (0)

Finding the cause of the problem

Since implementing the Cisco NAC, I’ve had a few fun calls that could have been avoided with a little more troubleshooting.  The calls always start with, “Hey, we’re having some NAC issues here.” and go down hill from there.  Here are a few issues initially blamed on the NAC with the true cause of the issue in parentheses.

There are a few more in the ever growing compilation list to be posted later.  I get at least two calls a weeks that are very face-palm worthy.  I’m thinking about setting up a wall-o’-shame at work.  Let the guilty party step forth.

Sometimes it’s more important to be human, than to have good taste. – Brecht

09.Dec.08 Humor, Networking, Security Comments (2)

The CAT matters

A network technician called me the other day about a network printer he was having a problem with. He said that he could ping the printer but printing was sporadic. When he tried to bring up the printer’s configuration web page, it would not load. It wouldn’t load for me either (I’m at another location). I asked if he had tried a different network port and he said he had but it still didn’t work.

I decided to check out the printer myself after a few other troubleshooting checks failed. It was nice to get out of the office for the short drive. When I got to the other location, the technician took me to the printer. The first thing I noticed was the color of the network cable. The cable was a dark blue. Those cables, I remembered, were pretty old and no longer being used because they are CAT 5. Almost all of our buildings are wired with CAT 6 for gigabit.

Before changing out the cable, I wanted to try a quick test. I went into the configuration of the printer via the front control panel and changed the network type from “Auto” to “100Mb Full-Duplex” (the printer supports gigabit). The printer was restarted and tested. We could now access the configuration web page and print jobs worked 10 out of 10 times.

The technician said he didn’t have any of the CAT 6 patch cables but would pick some up at our office later. I reminded him to change the network type back to “Auto” after he changed out the cable. Not that it would really matter because I doubt moving from 100MB to gigabit would spit out the prints any faster.

When prosperity comes, do not use all of it. – Confucius

25.Oct.08 Networking Comments (0)

It’s working? Holy crap! It’s working!

The Cisco NAC is finally working!  Here are the two main things that made it start working:

I have four remote locations set up with the site Cisco Clean Access Server (CAS) reporting back to a centralized Clean Access Manager (CAM). All four sites had zero issues with users being able to log on, install the agent and get authenticated. Even logon scripts are running properly thanks to a loop that pings a specific set of IPs. Those IPs are blocked by default and can only be reached once the user is dropped into their appropriate user role. Successful ping = logon script execution.

I’ve still got about 20 locations left. Right now, the NAC is only performing authentication and assessing whether or not Windows updates are installed. Once I have all of the locations up, I’m going to implement a few more checks (i.e. antivirus software running and updated). I tested the AV check on a couple of users and it worked properly so I don’t expect any big issues when I role the check out for all locations.

Consider the postage stamp: its usefulness consists in the ability to stick to one thing till it gets there. – Josh Billings

16.Oct.08 Networking, Security Comments (0)