Maak geen slapende honden wakker is in het engels:
Let sleeping dogs lie.


Die roadrunner springt aardig van de hak op de tak.
Nu dan eens wordt dat veroorzaakt door Big Blue.
Zie bijvoorbeeld http://www.redbooks.ibm.com/abstracts/SG246880.html?Open

IBM WebSphere Application Server for z/OS V6 is a complex product made up of many components. This IBM Redbook focuses on the problems that you can experience with WebSphere for z/OS. It is intended for system programmers and administrators who need to identify, analyze, and fix problems efficiently so that they can deliver good support for the WebSphere environment.

Het zomaar kunnen zijn dat je al die complexiteit niet nodig hebt.
En hoezo "fix problems" als die in WebSphere zelf zitten en niet in de applicatie of de database?

Niets aan de hand zou je zeggen totdat je "rare meldingen" krijgt, zoals:

SRVE0095I: Servlet has become temporarily unavailable for service: {0}

Problem	Specified servlet is temporarily unavailable.
User response	Wait and retry operation. Servlet might have been removed from service by server administrator.

en ooit gehoord van First Failure Data Capture (FFDC)?
FFDC genereert bij een WebSphere fout een logfile, die eeder voor IBM bedoeld is, dan de nijvere programmeur.
Zie http://publib.boulder.ibm.com/infocenter/wasinfo/v6r0/index.jsp?topic=/com.ibm.websphere.base.doc/info/aes/ae/ctrb_ffdc.html

The first failure data capture (FFDC) log file saves information that is generated from a processing failure. These files are deleted after a maximum number of days has passed. The captured data is saved in a log file for analyzing the problem.

Amazing, naar mate de tijd verstrijkt, lossen problemen zich vanzelf op. En hoezo heet dit fenomeen First Failure?

Maar lees verder:

The first failure data capture feature preserves the information that is generated from a processing failure and returns control to the affected engines. The captured data is saved in a log file for analyzing the problem. FFDC is intended primarily for use by IBM Service. FFDC instantly collects events and errors that occur during the WebSphere Application Server runtime. The information is captured as it occurs and is written to a log file that can be analyzed by an IBM Service representative. The data is uniquely identified for the servant region that produced the exception.

Is dit de Dr. Watson van Websphere?

Wat betekent het voor de onschuldige webapp?

Of geldt hiet het adagium: Java, write once debug everywhere?
Zie http://en.wikipedia.org/wiki/Write_once,_run_anywhere