Apr 142011
 

Today I was trying to help someone with a regular expression to match an e-mail address.  He was developing on a Solaris server and sent me the regular expression outlined in RFC 822 which outlines message formatting for e-mail headers.  The command he sent me to test with took a little tweaking, but I eventually came up with:

Pretty straight-forward.  Search for any alphanumeric, dot, underscore, percent sign, plus sign, or dash, repeating one or more times followed by an ‘@’ sign, then another alphanumeric, dot or dash, repeated one or more times, a dot, and then an alphabetical character repeated 2, 3, or 4 times.

The thing that gets me is that this command worked on my Mac.  It worked on a Linux server.  I sent it back to him, he tried it, and… it didn’t work.  After poking around a little bit, I determined that it was because on Solaris for this to work correctly, you need to use /usr/xpg4/bin/egrep rather than /bin/egrep, which brings me to the original reason for this post.  On Solaris, there are no fewer than four places where you may find standard OS commands – /bin, /usr/xpg4/bin, /usr/ucb, and /usr/sfw/bin.  A couple other third party distributors will also package core OS utilities (like the GNU toolset) and install them in their own directory under /opt.

Larry Ellison and His Sausage

Larry Ellison - It's his sausage, but it's not his fault.

 

I’d like to blame Oracle for this, but quite frankly, Sun has been doing this since I can remember with Solaris 2.5.1, which is the earliest version I’ve worked with.  I’ve been getting annoyed by this quite frequently lately, and it was finally time for me to vent.  Thank you for listening and remember, when you are on Solaris and you want to run a basic command, you must choose.  But choose wisely.  Today, with /bin/egrep, I chose… poorly.

Apr 092011
 

I was browsDean Markely Strings - Regularing around on Amazon a couple weeks ago and I came across these beauts.  The Dean Markley vintage re-issue strings, regular gauge.  I used to play these things back in the 90′s and I absolutely loved them.  They maintain great tone and last longer than other strings I’ve tried.  The best part is the regular gauge are sufficiently heavy to fit my taste (.10 tops, .46 bottoms).  I picked up a set and they are just like I remember.  The only thing missing is the Dean Markley sticker that came in every pack.  That was a little disappointing.  In any case, a great set of strings.  I might try the light top heavy bottoms next time, but those may be a little heavier than what I want to put on my Strat.

Apr 052011
 

One of the most frustrating things about using Red Hat Enterprise Linux or CentOS in an enterprise environment, in my opinion, is maintaining updates on hosts that are supposed to be identical and are in different environments, like dev, test, and production.  In the past, I’d roll out patches to my dev server, run yum update (or up2date) on my test servers, and then do the same in production.  By the time I got through with production, dev and test would be off a bit and production would generally have at least a dozen rpm’s that were newer than their dev and test counterparts.  This is attributed to the frequency with which bug fixes, security, and other errata are released for these distributions.  In an enterprise environment with auditing requirements in place, this can cause a real pain in the neck.

This is the first reason I started testing out Spacewalk.  Spacewalk is the upstream project for Red Hat Network Satellite, which allows you, for all intents and purposes, to have an RHN install right in your own datacenter.  The benefit that added to me originally was simply being able to choose a cut off date for syncing patches, apply those patches to my systems, then resume syncing again.  This ensures all of my systems have the same package version.  If you’re familiar with Red Hat Network at all, you’ll know that there is a lot of gravy too.  It lets you work with groups of servers, create custom channels, provision servers, execute remote commands, manage configuration files on clients, provision new hosts, and monitor clients as well.  There is a web-based API that leverages XML RPC that you can script against.

It took a lot of work up front to get set up, but it’s getting to the point where managing the systems is a breeze.  In my opinion, Spacewalk is still a little buggy, but as of version 1.3 which is current at the time of this writing, stability and functionality has increased dramatically since I started working with version 0.6.  If you’re looking for a way to manage your Linux systems (including Red Hat Enterprise, CentOS, Scientific, or Debian), I highly suggest taking a look at Spacewalk.