[comp.protocols.kerberos] Database Frobbing

haynes@ucscc.UCSC.EDU (99700000) (12/15/90)

In article <9012142229.AA11803@delwin.MIT.EDU> jon@MIT.EDU (Jon A. Rochlis) writes:
>
>Other than that we generate the dump files, awk/sed/join them to our
>hearts content and then reload.  If you've got a slave then you don't
>need to have any downtime.
>
What kinds of things are you doing when you do these operations?
We're still on the threshold of worrying about how to run an Athena
installation; and most of the operational system-administrator-type
procedures seem to be all in people's heads.
haynes@ucscc.ucsc.edu
haynes@ucscc.bitnet

"Any clod can have the facts, but having opinions is an Art."
        Charles McCabe, San Francisco Chronicle

jon@MIT.EDU (Jon A. Rochlis) (12/16/90)

   >
   >Other than that we generate the dump files, awk/sed/join them to our
   >hearts content and then reload.  If you've got a slave then you don't
   >need to have any downtime.
   >
   What kinds of things are you doing when you do these operations?
   We're still on the threshold of worrying about how to run an Athena
   installation; and most of the operational system-administrator-type
   procedures seem to be all in people's heads.

About the only time we do such things is to remove user's who have
graduated.  We move the user's who don't show up on the registrar's
tape into the "deactivated" state in Moira.  After enough time goes by
for correcting mistakes, we remove the users from Moira (and generate
a script to nuke their disk space, etc.).  Given the list of nuked
users we awk/join whatever them out of the kerberos database.  That's
about it.  Doesn't happen often.

We have also gone through and fixed expiration times en masse (some early
programs created principal's with expiration time of now + 2 or 3
years).  

		-- Jon

martin@iastate.edu (Calsyn Martin Robert) (12/17/90)

We were faced with a need to add 300+ rcmd.hostname entries to the
database and so created a program capable of adding principals from a
file.  The principals are added with random keys, so to create user
principals would require a modification to generate useful passwords.

We use a heavily modified version of Moira and the registration server
and so, as at MIT, users obtain their principals at the time they
register.  Deleting principals is a particular nuisance.  Jon, is there
a particular reason why kdb_edit, or some such program, doesn't support
a delete operation.  The underlying database systems (dbm, ndbm) are
certainly capable of it. Am I breaking a design constraint if I add such
a function?

Martin R. Calsyn                                   martin@iastate.edu
Project Vincent Systems Support                    gg.mrc@isumvs.bitnet
Iowa State University Computation Center           voice: (515) 294-9889 
Ames, Iowa 50011                                   fax:   (515) 294-1717

jon@MIT.EDU (Jon A. Rochlis) (12/19/90)

   Deleting principals is a particular nuisance.  Jon, is there
   a particular reason why kdb_edit, or some such program, doesn't support
   a delete operation.  The underlying database systems (dbm, ndbm) are
   certainly capable of it. 

Simple conservatism.  If it's difficult to delete principals then it's
not likely to happen unless you really want it to.

   Am I breaking a design constraint if I add such a function?

Not as long as you're will to come in at 3:00am and pick up the pieces
when a bug in Moira deletes half of your Kerberos database.  We'd
rather delete people from Moira, remove their mailing list pointer,
etc, (all of which can be undone easily) and then at our lesiure
delete principals from the Kerberos databse by doing a dump/awk/join
cycle.  It's up to you to weigh the tradeoffs for yourself.  Our call
won't make everyone happy.

		-- Jon

jtkohl@MIT.EDU (John T Kohl) (12/19/90)

Martin asks "is there a particular reason why kdb_edit, or some such
program, doesn't support a delete operation".

Besides the reasons Jon Rochlis gave, there's also a security-related
one.  If you delete names and they get re-used, there's a chance that
the new owner of the name may get unintended access to services which
have the name on an Access Control List, but didn't remove it when the
old principal was destroyed.

John