>From: Bill Bogstad >Subject: BBLISA: BBLISA meeting, Nov. 14: Dr. Alva Couch of Tufts University >Date: Mon, 05 Nov 2001 23:24:50 -0500 > > >I hope you haven't made plans for next week yet. Alva Couch from >Tufts University will talk about configuration change management and >dependency analysis. Alva is on the program committe for LISA 2001 >and has been interested in system administration research for some >time. -- Bill Bogstad > >-------------------------------------------------------------------- >======== ======== >======== BackBayLISA Calendar of Events ======== >======== ======== >-------------------------------------------------------------------- > > >November: November Meeting > >Date: November 14, 2001 >Time: 7:00-9:00 PM > >Location: MIT > Building E51, Room 149 > Corner of Amherst & Wadsworth Streets > Cambridge, MA > >Schedule: 7:00-7:30 Introductions/Resume Sharing/Job Openings > 7:30-9:00 Presentation and discussion > 9:00-?? Adjourn to local eating/drinking > establishment > >Coordinator: Bill Bogstad (bogstad@pobox.com) > >Speaker: Dr. Alva Couch > Professor > Tufts University > >Topic: Open and closed worlds: practical global dependency analysis > >Description: > > One of the main challenges for system administrators is to >accurately determine the true effect of a particular configuration >change. There are two schools of thought on how this should be done. >In the 'closed-world' model, one limits one's actions so that their >effects are inherently predictable. In an 'open-world' model, one >allows more freedom of action at the expense of having to analyze the >effect of any action. While we would all like to live in predictable >worlds, expediency often dictates an open-world approach, especially >when mixing vendor-supplied and open-source software within one >server. > > The problem with open worlds is that local actions can have >global effects. In this talk, I'll discuss "global dependency analysis" >and how it can help one to predict the effects of one's actions in >making changes to a UNIX server. I'll illustrate the concept with two >simple tools for reporting the global structure of UNIX dynamic >library dependencies and symlink trees. Both tools invert one-way >bindings of the form "X uses Y" into statements of the form "Y is used >by X1, X2, ...". This inversion exposes the otherwise hidden global >effects of making a local change to Y, and allows one to plan how to >handle those effects before making a change. When applied to daemons >started at boot time, this approach exposes potential circular >dependencies in booting that can be corrected by relocating files from >remote to local filesystems. > >======================================================================== > > >Directions: > An ASCII map of the immediate area is appended. > > A better map is located at: > http://www.bblisa.org/#mit_directions > > Park on-street or in the MIT lot on Hayward St. > >======================================================================== > > > *********************************** > * ASCII Map to MIT Building E51 * > *********************************** > > > > \ // > \Broadway // > \ // // > T \ // // > \ // // > Main St. \ // Longfellow // > --------------+---------+------+------++--)------------(--++-- > | | // Bridge // > |Hayward |Wadsworth // // > P | St. | St. // // > | | // // > Amherst St. | | // // > --------------+---------+ //Memorial // > E51 \ //Drive // > \ // // > \ // //Storrow > M. I. T. ++ Charles //Drive > // River // > // // > // // > Key: > E51 -- Building E51 > T -- Kendall Sq. MBTA stop (red line) > P -- MIT parking lot > > >======================================================================== > > >--- >Send mail for the `bblisa' mailing list to `bblisa@bblisa.org'. >Mail administrative requests to `majordomo@bblisa.org'. > Thanks! John Malloy johnmalloy@mediaone.net