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Hi Rich, > When I want to upgrade the TDS, I follow this procedure: > > cd <tomcat>/webapps > ../bin/shutdown.sh > rm thredds.war > rm -rf thredds > wget ftp://ftp.unidata.ucar.edu/pub/thredds/4.0/thredds.war > ../bin/startup.sh > > This was okay when only I was using the system, but now that it's > getting popular I'm wondering if I can be let disruptive. > Is this all necessary? Shutting down Tomcat is not absolutely necessary. You can instead undeploy the running TDS and then deploy the new version. But PermGen OutOfMemoryErrors start to come up (see the note below [1].) Also, I don't think it is any less disruptive than your method; there is still a time when the TDS is down. I tend to use the Tomcat manager, but I still shutdown and startup Tomcat most times I deploy a new version. Besides the PermGen issue[1], another reason I shutdown/startup Tomcat is so that I can clean up the log file directories without worrying about which files Tomcat is using. > Also, if the TDS is reloaded while someone is accessing data from the > TDS, what happens? I believe shutdown and stop/undeploy are fairly graceful in that things that have started are allowed to finish. While the TDS is down, of course, requests will get either 404 not found responses or, if Tomcat is down, no connection will be made. During the startup/deploy process, things might be a bit sluggish but requests should be handled normally. Hope that helps, Ethan Notes: [1] PermGen OutOfMemoryErrors can crop up if you undeploy/deploy TDS rather than stop/start Tomcat. Some notes on that in the TDS Tutorial: http://www.unidata.ucar.edu/projects/THREDDS/tech/tutorial/BasicTomcatAndTDSSecurity.html#PermGenProblem and a good article on the topic: "Return of the PermGen" - http://my.opera.com/karmazilla/blog/2007/09/29/return-of-the-permgen Ticket Details =================== Ticket ID: BOZ-874608 Department: Support THREDDS Priority: Normal Status: Closed