Unix Tip: Using SCAT (Solaris CAT) for analyzing crash dumps

2 comments | 5I like it!
April 23, 2008, 12:20 PM —  ITworld.com — 

Want to do something with those crash dump files other than remove them? Want to extract some useful information without a lot of work? Take a look at Sun's free crash analysis tool, scat.

While "scat" in this context stands for "Solaris Crash Analysis Tool", I find myself drawing an analogy to the other meaning of the word. "Scat" refers to the dung of certain animals. Analysis of animal scat can tell you a lot about the health and the diet of the particular animals and can be useful in identifying the species as well. Similarly, scat analysis of the system variety can provide useful information for diagnosing the ailments of your Solaris servers -- in particular, what caused them to crash. Examining the "droppings" of a system can require considerable skill if you end up delving deeply into the crash dump files. At the same time, even the simplest use of the scat command can provide you with some of the most telling information about a crash. You simply give the tool the numeric identifier of the crash dump you want to know about. If your crash dump files are unix.0 and vmcore.0 (i.e., the first set of a possible collection of crash dump files), for example, you would issue commands such as these:

# cd /var/crash/boson
# /opt/SUNWscat/bin/scat 0

Notice that, since the scat program wants only the numeric identifier for the crash dump files, you must first cd to the directory in which these files are stored.

The unix.X and vmcore.X files are generated when a Solaris system panics and are normally stored in /var/crash/`uname -n`. The initial output from scat will identify the system and provide information on the date and time the system crashed, how long the system had been up at the time, the system type, hostid, panic string, etc. Here's an example:

  Solaris[TM] CAT 4.1 (build 526) for Solaris 9 64-bit SPARC(sun4u)

  Copyright © 2003 Sun Microsystems, Inc. All rights reserved.
  Patents Pending. Use is subject to license terms.
  Sun Microsystems proprietary - DO NOT RE-DISTRIBUTE!

  Feedback regarding the tool should be sent to SolarisCAT_Feedback@Sun.COM

opening vmcore.0 ...dumphdr...symtab...core...done
loading core data: modules...panic...memory...time...misc...done
loading stabs...read_type_db: Wrong number of lines in database, or database
doesn't end in a newline
unable to load any stabs file
patches... - NOT AVAILABLE (No such file or directory) done

core file:      /var/crash/boson/vmcore.0
user:           Super-User (root:0)
release:        5.9 (64-bit)
version:        Generic_112233-11
machine:        sun4u
node name:      boson
domain:         lab.particles.org
hw_provider:    Sun_Microsystems
system type:    SUNW,Sun-Fire-V210
hostid:         837844c7
time of crash:  Tue Apr 22 11:49:52 EDT 2008
age of system:  22 hours 5 minutes 4.48 seconds
panic cpu:      0 (ncpus: 1)
panic string:   free: freeing free block, dev:0x200000016e, block:32032, ino:6057255, 
                fs:/homes

running sanity checks.../etc/system...ndd...sysent...misc...done
SolarisCAT(vmcore.0)>

Sign up for ITworld's Daily newsletter
Follow ITworld on Twitter @IT_world

I like it!
Close

On Twitter now

Unix

Powered by Twitter
You are logged in | Sign out
Sign in and post to Twitter

What are you thinking?

Cancel Tweet sent

On Twitter now

Comments

GREAT article!! I always

GREAT article!! I always look forward to them, they are so imformative.

You said: "However, it's not too hard to pick out additional evidence that the crash was due to a ufs failure. It takes considerable familiarity with the system calls included in the analyze output to identify the sequence as the removal of a large file"

But what was it that tipped you off to this?
| reply

replica bags

Tourism can relax one's body and mind .People choose to go out at the National Day Holiday .Many of them will go abroad ,Franch 、England may be their first choice ,as these countries have many classical buildings replica handbags .And Franch is the mother country of fashion.
| reply
peer-to-peer

Esther Schindler
If the comments are ugly, the code is ugly

claird
SVG a graphics format for 21st century

pasmith
Take Chrome OS for a test spin

Sandra Henry-Stocker
Solaris Tip: Have Your Files Changed Since Installation?

sjvn
64-bits of protection?

jfruh
Android fragments vs. the iPhone monolith

mikelgan
What Gizmodo missed about the Pro WX Wireless USB disk drive

 

Sidekick: The Good News & the Bad News
Either way you look at it Microsoft Data Center management did not follow standards or best practices in this failure. In which case it makes me wonder more about the outsourcing of corporate data much less personal data.
- mburton325

Join the conversation here

The Daily Tip

The Daily TipQuick, practical advice for IT pros. Made fresh daily.

Hot tips:

Want to cash in on your IT savvy? Send your tip to tips@itworld.com. If we post it, we'll send you a $25 Amazon e-gift card.

Newsletters

Subscribe to ITWORLD TODAY and receive the latest IT news and analysis.

I would like to receive offers via email from ITworld partners.
By clicking submit you agree to the terms and conditions outlined in ITworld's privacy policy.
Featured Sponsor

AISO founders envisioned a Web hosting company that was environmentally friendly. While the company employed energy-efficient innovations like solar panels, its infrastructure produced unacceptable power and cooling requirements. Find out how AISO leveraged AMD technology to overcome their challenge in this case study white paper.

In this whitepaper, Scalar explores the opportunity to change the landscape with respect to mission critical databases built around Oracle. Leveraging technologies such as Linux, high-end commodity processing power and Oracle RAC technology to architect, design, build and maintain database infrastructure that delivers maximum availability, reliability and performance at a fraction of traditional cost.

On a typical day, weather.com, the Web site for The Weather Channel in Atlanta, serves up between 15 million and 20 million page views. But in September 2004, when back-to-back hurricanes ransacked Florida, the peak traffic on one day more than tripled: over 70 million page views by more than 7 million unique visitors. Read the full success story now.

Marketplace