Date: Fri, 22 Sep 1995 11:32:48 -0400 (EDT) From: Bill/Carolyn Pechter <pechter@shell.monmouth.com> To: peter@taronga.com (Peter da Silva) Cc: freebsd-chat@freefall.FreeBSD.org Subject: Re: ports startup scripts Message-ID: <199509221532.LAA10231@shell.monmouth.com> In-Reply-To: <199509221344.IAA20558@bonkers.taronga.com> from "Peter da Silva" at Sep 22, 95 08:44:37 am
next in thread | previous in thread | raw e-mail | index | archive | help
> > Any particular reason you didn't CC hackers? > > > I'd prefer at least 5 > > 0 -- halt > > Ss -- single user > > 1 -- sysadmin > > How do these differ? I've never been able to figure out just what the point > of having three single-user levels in System V is. The Ss single user startup is the same as BSD single user. The 1 level on the machines I've seen runs the things like sync, cron, and a getty on the console... It's real nice for testing things like startup without letting users on via the net or over serial port gettys. I've used it as a final check before going to run states that let real users get at the machine. (Not too useful in workstations -- I agree -- but real slick on mini's and mainframe size multiprocessors.) > > Don't they logically fit in "server"? I do Oracle startup at level 3. Sometimes you just want everything up except the database -- like during exports of the database and backups. Since dropping from 4 to 3 shuts the db down you've got an easy automated backup method -- since cron could just change the run state, back up, and then go run level 4 again. I've done this with drops to run state 1 at times under Linux at home to automate a lot of backups. (It's real hard to do Single user cron'd backups 8-)...) Actually the a,b,c run states are supposed to be used for stuff like Oracle/Sybase etc. But no one really uses them. (If anyone has please let me know.) In 4 years of Unix training classes I've never found anyone who's used them except me. I just did it Beta'ing SVR4 to check the stuff worked as advertised. (I did find that Pyramid's DC/OSx -- which was ported to R3000 from i386 SVR4 asked to insert the floppy in the A drive and hit return when checking the "backup command." Of course, the machine had no floppy drive.) > > We could also do some security work here. If we can set things up that no > network services are available off-system at run level 2 (this would take > some work in daemons) then run level 2 would be effectively "firewalled". > You would run at level two when connecting to the Internet, for example. > > The problem is sendmail. You need to have sendmail running for local mail > to work. It would have to be made smart enough to refuse connections from > anywhere but localhost at level 2. Or could sendmail be classified as a > client service? > Sure... The great thing about Unix is the configurability and ease of modification. Run states give more -- not less options. You can always skip 'em if you don't want them. Here's an idea (kludge alert) off the top of my head... You could always run with two different sendmails and two sendmail.cf files. One for local delivery and UUCP only and one that knows about the internet and name server and switch 'em. (or is that too wierd). Bill ------------------------------------------------------------------------------- Bill Pechter | The postmaster always pings twice. Lakewood MicroSystems | 17 Meredith Drive, 908-389-3592 | Tinton Falls, NJ 07724 pechter@shell.monmouth.com |
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199509221532.LAA10231>