Re: recovering from a power outage
On Thursday 12 February 2009 16:24:25 A. Wright wrote: > Can anyone corroborate that? If so, does anyone know when > ed started wanting to make a temp file even before any edits > are made? I am sure that ed has gotten me out of similar jams > in the past, when I wanted to see part of a file in an unchecked > root fs, and cat wouldn't fit the bill because the file was > too long (and more and friends are far away on /usr, and therefore > not available if still patching up the root). From ed(1): FILES /tmp/ed.* buffer file Solution: mdconfig -a -t swap -s 64m -o reserve -u 0 newfs -U /dev/md0 mount /dev/md0 /tmp chmod 1777 /tmp Also, there's /rescue/vi (since 7.0 I believe), which will complain about /var/tmp/vi.recover, which you can a) ignore or b) use above procedure with -u 1 to create /var/tmp. -- Mel Problem with today's modular software: they start with the modules and never get to the software part. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: recovering from a power outage
On 2/13/09 7:22 AM, Robert Huff wrote: > >>IMHO, if you are running a system where 'power outages' cannot >>be tolerated, why not install a UPS, they are really quite >>cheap, and be done with it? I cannot imagine any high end, >>mission critical system not employing one. > > Power outages are not the only thing which can cause (directly > or indirectly) file system corruption. Hi, I'm the OP :-) To that point, the system in question is attached to a 5000VA UPS. I did something stupid with the UPS control software that caused an, er, unscheduled shutdown. No UPS can help Mr. Fat Finger! Thanks for all your replies. dn ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: recovering from a power outage
On Fri, 13 Feb 2009 10:22:55 -0500, Robert Huff wrote: > Power outages are not the only thing which can cause (directly > or indirectly) file system corruption. Oh yes, that's so true - I experienced it in July 2008, and I still think it was a software problem... -- Polytropon >From Magdeburg, Germany Happy FreeBSD user since 4.0 Andra moi ennepe, Mousa, ... ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: recovering from a power outage
On Fri, 13 Feb 2009 10:22:55 -0500 Robert Huff wrote: >> IMHO, if you are running a system where 'power outages' cannot >> be tolerated, why not install a UPS, they are really quite >> cheap, and be done with it? I cannot imagine any high end, >> mission critical system not employing one. > > Power outages are not the only thing which can cause (directly > or indirectly) file system corruption. I agree, a sledge hammer applied to the HD could also cause irreparable harm; however, the subject of this thread referred to 'power outages'. The use of UPS, RAID, backups, etc. all tend to insure the safety of data. In this case, the OP only referenced 'power outages'. -- Jerry ges...@yahoo.com People that can't find something to live for always seem to find something to die for. The problem is, they usually want the rest of us to die for it too. signature.asc Description: PGP signature
Re: recovering from a power outage
>IMHO, if you are running a system where 'power outages' cannot >be tolerated, why not install a UPS, they are really quite >cheap, and be done with it? I cannot imagine any high end, >mission critical system not employing one. Power outages are not the only thing which can cause (directly or indirectly) file system corruption. Robert Huff ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: recovering from a power outage
One of my machines has a pair of 50gb SCSI disks; running two full passes takes about 7 minutes. I have no idea how long it might take to check a multi-terabyte RAID- set-up. depends of how filesystem was created. multiterabyte arrays are usually used for large files, and filesystem with 64K blocks and 8K fragments and say one inode/megabyte is checked VERY quickly. Still worth waiting ... in my opinion. Robert Huff ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: recovering from a power outage
On Fri, 13 Feb 2009 14:16:13 +0100 Polytropon wrote: > On Fri, 13 Feb 2009 08:11:56 -0500, Robert Huff > wrote: >> One of my machines has a pair of 50gb SCSI disks; running two >> full passes takes about 7 minutes. >> I have no idea how long it might take to check a >> multi-terabyte RAID- set-up. > > It's not *that* hard to wait for an fsck. I have 2 x 500 GB here at > home, you're right, it takes several minutes for fsck to check both > disks, but in the end, you're happy that either everything turns out > to be okay or, if problems occured, you see these problems and can > decide how to handle them. > >> Still worth waiting ... in my opinion. > > I'd rather wait than lose data. > > But as you said, it's very individual how you think about this. If > backups are done properly, sometimes it might even be easier *not* to > repair data, but to put back the backups on the newly initialized > disks... IMHO, if you are running a system where 'power outages' cannot be tolerated, why not install a UPS, they are really quite cheap, and be done with it? I cannot imagine any high end, mission critical system not employing one. -- Jerry ges...@yahoo.com Your temporary financial embarrassment will be relieved in a surprising manner. signature.asc Description: PGP signature
Re: recovering from a power outage
On Fri, 13 Feb 2009 08:11:56 -0500, Robert Huff wrote: > One of my machines has a pair of 50gb SCSI disks; running two > full passes takes about 7 minutes. > I have no idea how long it might take to check a multi-terabyte > RAID- set-up. It's not *that* hard to wait for an fsck. I have 2 x 500 GB here at home, you're right, it takes several minutes for fsck to check both disks, but in the end, you're happy that either everything turns out to be okay or, if problems occured, you see these problems and can decide how to handle them. > Still worth waiting ... in my opinion. I'd rather wait than lose data. But as you said, it's very individual how you think about this. If backups are done properly, sometimes it might even be easier *not* to repair data, but to put back the backups on the newly initialized disks... -- Polytropon >From Magdeburg, Germany Happy FreeBSD user since 4.0 Andra moi ennepe, Mousa, ... ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: recovering from a power outage
Wojciech Puchar writes: > background_fsck="NO" > > in rc.conf > > unix doesn't crash every few hours so it's really not a problem > to wait a bit more Cases and personal tolerance may vary. One of my machines has a pair of 50gb SCSI disks; running two full passes takes about 7 minutes. I have no idea how long it might take to check a multi-terabyte RAID- set-up. Still worth waiting ... in my opinion. Robert Huff ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: recovering from a power outage
seeing fsck checking partitions after unclean shutdown, but when everything's okay, there's no problem running into MUM *afterwards*. exactly like me i have background_fsck="NO" in rc.conf unix doesn't crash every few hours so it's really not a problem to wait a bit more ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: recovering from a power outage
On Thu, 12 Feb 2009 23:00:16 -0500, Robert Huff wrote: > 1) It was my understanding one has to force-mount a dirty > filesuystem. IF this sounds like a practice best left to senior > Jedi Masters ... it porbably is. Mounting possibly defective file systems is not a good idea. If it's possible, boot into SUM via boot -s first, check partitions (unmounted!) and then mount -a. Use "exit" to bring up MUM afterwards. Setting background_fsck="NO" in /etc/rc.conf may increase boot time if problems occur, but can be useful to first check for errors, and then bring up the system, instead of bringing up the system with maybe problems on the partitions. I think this delay is something you can affort. It's not good to fsck a mounted partition anyway, because fsck can repair minor defects on its own. > 2) I would _never_ let background fsck "take care of things" > after a crash, While hovering over the keyboard is a pain, I will > find out how badly things are damaged, rather than have boatloads of > files mysteriously vanish. That's a good concept which I do follow myself, too. I spend some minutes seeing fsck checking partitions after unclean shutdown, but when everything's okay, there's no problem running into MUM *afterwards*. -- Polytropon >From Magdeburg, Germany Happy FreeBSD user since 4.0 Andra moi ennepe, Mousa, ... ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: recovering from a power outage
David Newman wrote: > > What's the canonical method for checking ufs file systems on a FreeBSD > 7.1/amd64 system after an unscheduled power outage? Wait. The system will automatically detect a dirty shutdown and check the disks during the boot process. If the disks are only mildly scrambled by the outage, the system will continue to boot and the filesystem check program will run in the background -- you'll notice some disk slowness until fsck is done cleaning things up, but things will be otherwise fine. See the man page for fsck and fsck_ffs for more details. -- Bill Moran http://www.potentialtech.com ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: recovering from a power outage
Jerry McAllister writes: > > > do I need to > > > boot into single-user mode, what filesystem(s) do I mount and how, > > > what switches if any do I use with fsck and so on. > > > > > i thought it happens in the background anyway. i don't recall having to > > do anything other than listen to the drive whirring away - and we've > > had many power outages! > > It does run in the background, but if you have time, it isn't a > bad idea to run it in single user before bring the whole system > back up in the circumstance of a catastrophic failure like a power > outage. 1) It was my understanding one has to force-mount a dirty filesuystem. IF this sounds like a practice best left to senior Jedi Masters ... it porbably is. 2) I would _never_ let background fsck "take care of things" after a crash, While hovering over the keyboard is a pain, I will find out how badly things are damaged, rather than have boatloads of files mysteriously vanish. Robert Huff ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: recovering from a power outage
On Thu, Feb 12, 2009 at 05:16:53PM -0800, prad wrote: > On Thu, 12 Feb 2009 16:45:18 -0800 > David Newman wrote: > > > do I need to > > boot into single-user mode, what filesystem(s) do I mount and how, > > what switches if any do I use with fsck and so on. > > > i thought it happens in the background anyway. i don't recall having to > do anything other than listen to the drive whirring away - and we've > had many power outages! It does run in the background, but if you have time, it isn't a bad idea to run it in single user before bring the whole system back up in the circumstance of a catastrophic failure like a power outage. jerry > > -- > In friendship, > prad > > ... with you on your journey > Towards Freedom > http://www.towardsfreedom.com (website) > Information, Inspiration, Imagination - truly a site for soaring I's > ___ > freebsd-questions@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org" ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: recovering from a power outage
On Thu, 12 Feb 2009, David Newman wrote:
On 2/12/09 4:41 PM, Jerry McAllister wrote:
On Thu, Feb 12, 2009 at 04:06:49PM -0800, David Newman wrote:
What's the canonical method for checking ufs file systems on a FreeBSD
7.1/amd64 system after an unscheduled power outage?
How about fsck
Right. I'm asking procedurally how that's invoked -- eg., do I need to
boot into single-user mode, what filesystem(s) do I mount and how, what
switches if any do I use with fsck and so on.
Normally after booting after a power outage fsck will run automatically
as part of the system startup, and will prune the filesystems
automatically. If it finds an error it can't fix without help, it will
drop you into a command line and tell you that there were errors that
require your input to fix.
At that point you can just run fsck {reported filesysem with errors}
ie:
fsck /dev/ad0s1e
Sometimes you may want to use the -y switch, but use it with caution.
man fsck for more info on other options.
- Jamie
thanks!
dn
jerry
thanks
dn
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Re: recovering from a power outage
[ deletia introducing discussion of fsck ] On Thu, 12 Feb 2009, Tim Judd wrote: It's part of the bootup scripts now. It runs in the background 60 seconds after the login prompt shows up (not exactly, but close to 60 secs) it's the background_fsck option that defaults to YES in /etc/rc startup. only if there's major problems will it bail out, screaming for help. it'll drop you into a shell telling you that the filesystems need repair. If you are paranoid (like I am) and want to watch everything happen, then it is nice that fsck will read /etc/fstab (if still present) and correlate filesystem names with devices, so you can just follow a sequence like this: (boot single user) fsck / fsck /usr fsck /var ...etc Once you have run fsck on /, you can mount it using mount -u -o rw / so that you can then run ed (which is in /bin). I am assuming that the reason you cannot use ed to look at a file until this point is because it wants to write the temporary buffer somewhere, even if there are no changes, and if / is readonly and nothing else is mounted, then /tmp is unavailable for this purpose. Can anyone corroborate that? If so, does anyone know when ed started wanting to make a temp file even before any edits are made? I am sure that ed has gotten me out of similar jams in the past, when I wanted to see part of a file in an unchecked root fs, and cat wouldn't fit the bill because the file was too long (and more and friends are far away on /usr, and therefore not available if still patching up the root). Anyone? Andrew. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: recovering from a power outage
On Thu, 12 Feb 2009 16:45:18 -0800 David Newman wrote: > do I need to > boot into single-user mode, what filesystem(s) do I mount and how, > what switches if any do I use with fsck and so on. > i thought it happens in the background anyway. i don't recall having to do anything other than listen to the drive whirring away - and we've had many power outages! -- In friendship, prad ... with you on your journey Towards Freedom http://www.towardsfreedom.com (website) Information, Inspiration, Imagination - truly a site for soaring I's ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: recovering from a power outage
David Newman wrote: On 2/12/09 4:41 PM, Jerry McAllister wrote: On Thu, Feb 12, 2009 at 04:06:49PM -0800, David Newman wrote: What's the canonical method for checking ufs file systems on a FreeBSD 7.1/amd64 system after an unscheduled power outage? How about fsck Right. I'm asking procedurally how that's invoked -- eg., do I need to boot into single-user mode, what filesystem(s) do I mount and how, what switches if any do I use with fsck and so on. thanks! dn jerry thanks dn It's part of the bootup scripts now. It runs in the background 60 seconds after the login prompt shows up (not exactly, but close to 60 secs) it's the background_fsck option that defaults to YES in /etc/rc startup. only if there's major problems will it bail out, screaming for help. it'll drop you into a shell telling you that the filesystems need repair. --Tim ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: recovering from a power outage
On 2/12/09 4:41 PM, Jerry McAllister wrote: > On Thu, Feb 12, 2009 at 04:06:49PM -0800, David Newman wrote: > >> What's the canonical method for checking ufs file systems on a FreeBSD >> 7.1/amd64 system after an unscheduled power outage? > > How about fsck Right. I'm asking procedurally how that's invoked -- eg., do I need to boot into single-user mode, what filesystem(s) do I mount and how, what switches if any do I use with fsck and so on. thanks! dn > > jerry > > >> thanks >> >> dn >> >> >> ___ >> freebsd-questions@freebsd.org mailing list >> http://lists.freebsd.org/mailman/listinfo/freebsd-questions >> To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org" > ___ > freebsd-questions@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org" > ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: recovering from a power outage
On Thu, Feb 12, 2009 at 04:06:49PM -0800, David Newman wrote: > What's the canonical method for checking ufs file systems on a FreeBSD > 7.1/amd64 system after an unscheduled power outage? How about fsck jerry > > thanks > > dn > > > ___ > freebsd-questions@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org" ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
