Archive
Posts from 2007
Slides from my FMA presentation
I gave a presentation on the Solaris Fault Management Architecutre (FMA) at the Atlanta opensolaris users group meeting this evening. If your curious what was discussed, you can look through the slides that were used for the presentation. I would like to thank everyone for coming out, and for being such a great audience. I would also like to thank Scott Dickson for putting the meeting together, and for getting the attendees some tasty pizza!
$ read more →Running the Solaris SNMP daemon as an unprivileged user
During much of my IT career, I have needed to support SNMP in one form or another. Typically the companies I have worked for deploy an SNMP agent to each server, and a network management station periodically polls this agent to retrieve health information. Most of the SNMP daemons I have worked with run as the user root by default, which opens a big gaping whole in system security. The Solaris SNMP daemon is no different in this respect, though you can configure it to run as a non-privileged user…
$ read more →Printing status displays in Perl scripts
While developing a Perl script this weekend to summarize Solaris zone usage, I wanted to display some type of status while my script did it's thing. My friend Clay came up with a cool way to do this, and I thought I would share it here in case others needed to do something similar. Here is the code: There may be a better way to do this (adding an additional module isn't an option), but I have yet to find it. Niiiiiice!
$ read more →Debugging Apache web server problems article
I just posted my article Debugging Apache web server problems from the July ‘07 issue of SysAdmin magazine to my website. If the need arises for you to debug problems with a server running Apache, hopefully the items described in the article will prove helpful.
$ read more →Using the DTrace hotspot provider to observe java object allocations
In my previous post, I discussed how jmap can be used to view the contents of the Java heap. Jmap is a wonderful utility for viewing heap utilization at a specific point in time, but it's not the best utiltiy for answer questions like "which call stack is allocating objects of type foo?", or "how many objects are being allocated per second?", or "what is the average size of allocated objects?". To answer these types of questions, we need to look to a more thorough instrumentation framework. One such framework is the DTrace hotspot provider which was introduced in Java 6, and provides a number of probes to dynamically instrument Java applications…
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