Yeah, -prelim is awesome. I first learned about this parameter from Jeremiah's blog too. Btw, what was used before -prelim - people attached to an existing (and ideally idle) server process using a debugger and called ksdhng(), ksudps(), ksudss() functions directly to dump hanganalyze, process-state or systemstate information... This sounds crazy, it actually is crazy, but can at least allow you to dump diagnostic info from a database whic is already hopelessly hung anyway... this used to be documented in metalink as well... -- Tanel Poder Oracle Troubleshooting Blog - http://blog.tanelpoder.com Online Troubleshooting Seminars - http://tech.e2sn.com/oracle-training-seminars On Tue, Mar 1, 2011 at 2:49 PM, Pavel <ocp.pauler@xxxxxxxxx> wrote: > Hi > Didn't hear about _prelim before. Thanks Mark! > > Best regards, > Pavel. > > 2011/2/28 Bobak, Mark <Mark.Bobak@xxxxxxxxxxxx> > > Hopefully, the MOS document adequately covers how to track down blocking >> session. >> >> >> >> However, what is one to do when you cannot connect to the database? >> >> >> >> Well, you might try the ‘-prelim’ option to SQL*Plus. >> >> >> >> You can read about how it works, here: >> >> >> >> http://oradeblog.blogspot.com/2007/10/sqlplus-prelim-connection.html >> >> >> >> -Mark >> >> * >> * >> >