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Re: Skipping fsck during boot with systemd?

Frédéric Marchal writes:
 > > Usually on shutdown you run sync that flushes the cache to the disk,
 > > cleanly preparing the disk for unmounting. The mount command should
 > > 'run' sync automatically when unmounting.
 > > 
 > > You run fsck on power up because the 'system does not remember' if it
 > > was shut-off cleanly or not. If the disks are clean and the last check
 > > is not too old, fsck just report this and does nothing. Else it takes
 > > care of the safety of your data.
 > Are you implying that the only purpose of fsck at boot is to recover from an 
 > unclean shutdown?

Theoretically yes. Indeed errors happen, so the policy to force the file
file system check is wise. If my memory does not fail me, it's not something
that's here from the beginning of times (aka 01/01/1970 :) :) :) ).

 > To my understanding, errors creeping into the file system are unavoidable in 
 > the real world, even without serious system crashes.
 > On the computer I'm using here (Debian Wheezy), automatic fsck at boot has 
 > been disabled from the beginning.

I never did such thing. I prefer to keep my machine running on the
basis that what wears out solid state electronic is the warm up/cool
down, and a broken computer is bad for both my wallet and the

Nevertheless, my machines do reboot, and sometimes I get a "check
forced".  But I don't recall getting one of these errors during one of
these forced check.

 > Maybe I don't understand what fsck at boot is meant to fix then…

These errors too. A File system may be not the most complex data
structure in the world, but a good maintenance is a good thing to do,
like checking the oil level in an engine. Fail to check the oil level
and to perform the appropriate changes and prepare (not) to get

 > > fsck may take time. Relax, it needs that time.
 > >
 > > "The bearing of a child takes nine months, no matter how many women
 > > are assigned." ["The Mythical Man-Month", Frederick P. Brooks, Jr.]
 > > 
 > > "Ghe voe tempo, se speta" ["it takes time, just wait", old Venice
 > > saying]
 > I understand all these. The question here is about controlling when
 > this time

When you do fsck at boot there is only the kernel using the machine.

No other users (multiuser machines are rare now, i know) no other
services running (and in these days there are more daemons in a
running laptop than in an Armageddon movie :), it is the perfect time
to do cleanup, fsck can run without any other thing trying to access the

Just like floor cleaning. Better to schedule it when nobody is likely
to pass on the given floor.

And yes, the sooner you fix an error, the better.

 /\           ___                                    Ubuntu: ancient
/___/\_|_|\_|__|___Gian Uberto Lauri_____               African word
  //--\| | \|  |   Integralista GNUslamico            meaning "I can
\/                 coltivatore diretto di software       not install
     già sistemista a tempo (altrui) perso...                Debian"

Warning: gnome-config-daemon considered more dangerous than GOTO

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