tanya@adds.newyork.NCR.COM (Tanya Katz) (05/08/89)
In article <1763@gbmatl.UUCP> Gary Mckenney writes: >According to the rc script in /etc fsck will force a reboot and therefore a >second fsck if it finds problems through the first fsck. In other words if >there is a permenent problem found by fsck I don't think you will be able >to boot up your machine. If I recall correctly the fsck in the /etc/rc file is "fsck -p" which is just a verification pass, and will not really repair any damage. If fsck fails continuously, there is this vicious boot-fsck loop that takes over, and nothing short of booting the floppy disk and doing fsck by hand will stop this. I discovered this after we had a sudden blackout one evening while I was editing a file. Usually fsck reveals a minor filesize problem, and it is easly corrected, but the bootup fsck doesn't correct as if it were fsck -y. Besides, you wouldn't want fsck to mysteriously clear files, anyway :-) In the past week or two there have been many discussions on whether the 3b1 is best left up and running continuously. I shut my computer down if I know I will not be home or it will not be used. I also disconnect the power strip from the wall during a thunder storm. It is because of this boot-up loop problem that I am afraid to let it run unattended. I have visions of a power outage, then this berserk computer trying in vain to reboot itself! Any Comments?? Tanya ------------------------------------------------------------------------------ ### ###### ###### ##### Tanya Katz (516) 231-5400 x430 # # # # # # # # # # # # # ##### ...uunet!ncrlnk!adds!tanya ####### # # # # # tanya.katz@adds.newyork.ncr.com # # ###### ###### ##### Applied Digital Data Systems, Inc. 100 Marcus Blvd., Hauppauge, NY 11788 ------------------------------------------------------------------------------
ecf_hap@jhunix.HCF.JHU.EDU (Andrew Poling) (05/10/89)
In article <1084@adds.newyork.NCR.COM> tanya@adds.newyork.NCR.COM (Tanya Katz) writes: [...] > >It is because of this boot-up loop problem that I am afraid to let it >run unattended. I have visions of a power outage, then this berserk >computer trying in vain to reboot itself! > >Any Comments?? I've heard a solution to this that is so simple I had to share it. Simply place a formatted floppy with the VERBOSE loader on it in the drive and close the drive door. When the power comes back up, it gets stuck asking you which disk to boot from. Of course there's always the "sacrificial Diagnostic Floppy" ;-) Andy -- Andy Poling andy@gollum.hcf.jhu.edu Network Services Group ecf_hap@jhunix.UUCP Homewood Academic Computing ECF_HAP@JHUVMS.BITNET Johns Hopkins University
dklann@heurikon.UUCP (David Klann) (05/11/89)
In article <1084@adds.newyork.NCR.COM> tanya@adds.newyork.NCR.COM (Tanya Katz) writes: > > [ Discussion about /etc/rc running fsck... ] > >Any Comments?? > >Tanya > Tanya (and others), I leave my 7300 on full time (with the exception of week-long vacations, etc.). I have removed the call to fsck from my /etc/rc. To me, it is silly to run fsck like that when booting. To get around file system problems I simply run fsck from the command line. I have yet (over a year) to find any major problems. It's too bad the UNIXpc kernel doesn't have/make use of the s_state field in the super-block. That would increase the certainty about the state of the root file system when booting. I'd love to set the file system state to "FsOKAY" as the last thing before shutting the system down. In fact I think I'll look into that very thing. That's it! All we need is a pair of utilities, one to set it, and a version of fsstat to check it. I'll post them if/when they're working... Comments? Flames? David Klann Heurikon Corporation {backbone}!uwvax!heurikon!dklann
alex@wolf.umbc.edu (Alex Crain) (05/11/89)
In article <331@heurikon.UUCP> dklann@heurikon.UUCP (David Klann) writes: >In article <1084@adds.newyork.NCR.COM> tanya@adds.newyork.NCR.COM (Tanya Katz) writes: >It's too bad the UNIXpc kernel doesn't have/make use of the s_state field in >the super-block. That would increase the certainty about the state of >the root file system when booting. I'd love to set the file system >state to "FsOKAY" as the last thing before shutting the system down. In >fact I think I'll look into that very thing. That's it! All we need is >a pair of utilities, one to set it, and a version of fsstat to check it. >I'll post them if/when they're working... > >Comments? Flames? I don't think that this will work, because the disk never gets unmounted. In order to unmount the disk, you would have to flush all the kernals buffers and guarentee that nothing will get written to disk after you mark the disk. This works on other systems because they have a root partition and a user partition that can be umounted separately. When the kernal reboots, it kills all the user processes and unmounts /usr, marking it clean. Then it shuts down, leaving / in an undetermined state (which is almost always ok). When the system starts up, it only has / to wory about, so it boots right quick. The problem I envision is having the kernal crash in between the marking of the disk and the reboot. The system would then come up, find the disk clean, and propagate the disk trash everywhere (or just over the inode table). Not likely, but likely enough that I won't do it to my machine. It is probably possible to partition the disk into / and /usr, but it more trouble then its worth, me thinks. Nice thought though. :alex Alex Crain Systems Programmer alex@umbc3.umbc.edu Univ Md Baltimore County umbc3.umbc.edu!nerwin!alex
jste@PacBell.COM (Joshua Stein) (05/11/89)
In article <331@heurikon.UUCP> dklann@heurikon.UUCP (David Klann) writes: > >I leave my 7300 on full time (with the exception of week-long vacations, >etc.). I have removed the call to fsck from my /etc/rc. To me, it is >silly to run fsck like that when booting. To get around file system >problems I simply run fsck from the command line. I have yet (over a >year) to find any major problems. > I've just stumbled on ot this leave it on/turn it off (and fsck) discussion. I'm a bit superstitious about stating that I turn mine off and on all the time with virtually no problems (arrggghh now I have to call out the repair- person because of the panic message on my screen). I don't really know the pros and cons of the matter (I've heard there's a greater and regular chance of spikes, and other electrical fizzzbungz, on power up). I do it basically because it's the only way that I can live with the box. In a small one bedroom apartment it's the only way I can sleep at night. I know. I'll move to a bigger place that I can't afford ;->. As regards why the way fsck is implemented on boot up I think the rational was this. The 3B1/UnixPC was designed as a OAS type system for naive (dumb? no just unwilling to learn ;->) users. Busy on the go executives, their clearical and secretarial staff, etc. The idea was that they would never understand either the file system (it's why you end up in the Filecabinet when you start unix from the Office for instance) or fsck. So they would never boot to single user and use fsck to fix the file system. Just call AT&T service; at a reason- able maintenance cost, of course ;->. Seems to make sense to me that if you feel comfortable witha more vanilla style system you could rewrite rc to boot in a way that makes YOU happy (for instance, run fsck and go to single user if there are problems (or give you the chance to go to single user). Since I have not been bit by this one (oops, now I'm for it) I haven't bothered,...yet. -- ******************************************************************************* Joshua Stein Pacific*Bell 415 823-2411 |"I make it a rule to never get involved the usual generic disclaimer goes here | with somone who's possessed ... well, uucp:{world}!pacbell!phyf!josh | it's more of a guidline than a rule"
tanya@adds.newyork.NCR.COM (Tanya Katz) (05/16/89)
In article <1762@jhunix.HCF.JHU.EDU>, ecf_hap@jhunix.HCF.JHU.EDU (Andrew Poling) writes: > > Simply place a formatted floppy with the VERBOSE loader on it in the drive > and close the drive door. When the power comes back up, it gets stuck > asking you which disk to boot from. > Hello again, Where is there a verbose loader and/or how do I go about creating one?? Also what precisely does "ldrcpy" do? Tanya ------------------------------------------------------------------------------ ### ###### ###### ##### Tanya Katz (516) 231-5400 x430 # # # # # # # # # # # # # ##### ncrlnk!adds!tanya ####### # # # # # tanya.katz@adds.newyork.ncr.com # # ###### ###### ##### Applied Digital Data Systems, Inc. 100 Marcus Blvd., Hauppauge, NY 11788 ------------------------------------------------------------------------------