chris@mimsy.UUCP (Chris Torek) (09/09/88)
In article <520@cra2.apctrc.UUCP> zjat02@apctrc.UUCP (Jon A. Tankersley) writes: >rc.boot trashes /etc/mtab before running /etc/umount -at nfs. This leaves >potential garbage on remote systems /etc/rmtab (remote mtab). It does more than just that. rc.boot is always run, even on a single- user boot. If your root file system gets corrupted---and as most of us know, anything that *can* go wrong *will* go wrong (someone at Sun seems to have forgotten)---the code that clobbers /etc/mtab will cause a continuous series of crashes and auto-reboots. The only way to recover is to boot from another machine, or from the distribution tapes. But if this is the first machine on your network, or the only one with source . . . ? (Praise to Aule for mini-roots.) -- In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 7163) Domain: chris@mimsy.umd.edu Path: uunet!mimsy!chris
david@elroy.Jpl.Nasa.Gov (David Robinson) (09/09/88)
In article <13448@mimsy.UUCP>, chris@mimsy.UUCP (Chris Torek) writes: < In article <520@cra2.apctrc.UUCP> zjat02@apctrc.UUCP (Jon A. Tankersley) < writes: < >rc.boot trashes /etc/mtab before running /etc/umount -at nfs. This leaves < >potential garbage on remote systems /etc/rmtab (remote mtab). < < It does more than just that. rc.boot is always run, even on a single- < user boot. If your root file system gets corrupted---and as most of us < know, anything that *can* go wrong *will* go wrong (someone at Sun < seems to have forgotten)---the code that clobbers /etc/mtab will cause < a continuous series of crashes and auto-reboots. The only way to < recover is to boot from another machine, or from the distribution < tapes. But if this is the first machine on your network, or the only < one with source . . . ? (Praise to Aule for mini-roots.) Or you could use the totally undocumented "-b" option to cause the Sun to boot without running /etc/rc.boot and hope you are not too corrupted. -- David Robinson elroy!david@csvax.caltech.edu ARPA david@elroy.jpl.nasa.gov ARPA {cit-vax,ames}!elroy!david UUCP Disclaimer: No one listens to me anyway!
zap@nada.kth.se (Svante Lindahl) (09/11/88)
In article <9192@elroy.Jpl.Nasa.Gov> david@elroy.Jpl.Nasa.Gov (David Robinson) writes: >In article <13448@mimsy.UUCP>, chris@mimsy.UUCP (Chris Torek) writes: >< It does more than just that. rc.boot is always run, even on a single- >< user boot. [....] >Or you could use the totally undocumented "-b" option to cause the >Sun to boot without running /etc/rc.boot and hope you are not >too corrupted. -b is documented. Take a look at boot(8s) and init(8). The documentation is however incorrect. boot(8s) claims: -b Pass the -b flag through the kernel to init(8) to skip execution of the rc.local script. which is not very likely, since rc.local is executed by /etc/rc and not directly by init. init(8) got it right though: It normally runs the sequence of commands in the script /etc/rc.boot (see rc(8)) to check the file system. If passed the -b flag from the boot program, init skips this step. I have not tried this. All this applies to SunOS 3.[45], I have no idea about 4.0. -- Svante Lindahl Front Capital Systems zap@front.se