Soft Mount vs. Hard Mount
Dongbo Hu
Can I use soft mount option in the NFS client's /etc/vfstab?
Thanks,
Dongbo
me
if you hard mount a fs and reboot the system and the fs is not
available
you will hang during the boot process.
bud
Tony Walton
>
> What's the advantages and disadvantages of soft mount vs. hard mount?
Try the mount_nfs manual page than come back and ask about anything you
don't understand:
hard | soft
Continue to retry requests until the server
responds (hard) or give up and return an error
(soft). The default value is hard.
Hard versus Soft
File systems that are mounted read-write or that con-
tain executable files should always be mounted with
the hard option. Applications using soft mounted file
systems may incur unexpected I/O errors, file corrup-
tion, and unexpected program core dumps. The soft
option is not recommended.
> Can I use soft mount option in the NFS client's /etc/vfstab?
You can, though taking into account the manual page extract above, you
may not want to.
--
Tony
B
would be useful.
/B
me <m...@nowwhere.com> wrote in message news:3BCDAFB9...@nowwhere.com...
Chris Thompson
[de-top-posting-applied]
>me <m...@nowwhere.com> wrote in message news:3BCDAFB9...@nowwhere.com...
>> Dongbo Hu wrote:
>>
>> > What's the advantages and disadvantages of soft mount vs. hard mount?
>> > Can I use soft mount option in the NFS client's /etc/vfstab?
[]
>> if you hard mount a fs and reboot the system and the fs is not
>> available
>> you will hang during the boot process.
>
>Mount it hard,intr. Can't figure out one single example where soft mounts
>would be useful.
And it so happens that "hard,intr" is the default ...
Even so, I prefer to use the automounter for all pre-configured NFS mounts
if at all possible, rather than putting them in /etc/vfstab.
Chris Thompson
Email: ce...@cam.ac.uk
br...@no.spam.panix.com
: [de-top-posting-applied]
:>me <m...@nowwhere.com> wrote in message news:3BCDAFB9...@nowwhere.com...
:>> Dongbo Hu wrote:
:>>
:>> > What's the advantages and disadvantages of soft mount vs. hard mount?
:>> > Can I use soft mount option in the NFS client's /etc/vfstab?
: []
:>> if you hard mount a fs and reboot the system and the fs is not
:>> available
:>> you will hang during the boot process.
:>
:>Mount it hard,intr. Can't figure out one single example where soft mounts
:>would be useful.
: And it so happens that "hard,intr" is the default ...
what about 'bg'
bg | fg
If the first attempt fails, retry in the back-
ground, or, in the foreground. The default is
fg.
D. Rock
> Dongbo Hu wrote:
You can put a "bg" to the mount options. While the mount is tried in the
background the boot process will then continue.
--
Daniel
the FS mount is tried in the
Tony Walton
True, though bg|fg and soft|hard are two different things.The OP was
asking about soft|hard.
Effectively, bg|fg refers to the process of mounting the remote file
system while soft|hard applies to operations that take place once the
file system is mounted.
--
Tony
Dongbo Hu
problem:
Two machines are both nfs server and client. Two days ago I shut down
the machines because of building poweroff. Next day when I turned them
back on, they waited for each other forever because of the dependence.
Eventually I had to go to single-user mode and change /etc/vfstab
temporarily to fix it. So I wonder next time when the same poweroff
happens, whether the machine can boot smoothly without playing
/etc/vfstab. I know automounter is a solution, but I am also curious if
it can be solved by changing the nfs mount options like bg | fg and soft
| hard? Since I cannot turn off and on the machines frequently to test
it, I want to get more information before I try.
Thanks again.
Dongbo
B
/B
B
Seriously speaking, a server that also mounts filesystems may
run into problems if a remote filesystem becomes unavailable/unshared etc,
with stale filehandles, hangups and all sorts of gob. Hasn't happened just
once for me with such setups anyway. Plus the problems you are describing...
/B
Dongbo Hu <hu...@mail.trc.upenn.edu> wrote in message
news:3BCEFE6A...@mail.trc.upenn.edu...
Rob Stampfli
>would be useful.
A read-only News partition?
Rob
Logan Shaw
>would be useful.
They'd be useful if you're trying to access a public NFS server; some
FTP sites make their archives accessible via NFS in addition to FTP.
For instance, try mounting wuarchive.wustl.edu:/archive via NFS. If
you do that via automounter (in /net), you probably want the mount to
go away if wuarchive.wustl.edu stops responding. At least, I would.
- Logan
--
"In order to be prepared to hope in what does not deceive,
we must first lose hope in everything that deceives."
Georges Bernanos
Tony Walton
>
> First, thanks for all of your messages. Let me tell you more about my
> problem:
>
> Two machines are both nfs server and client. Two days ago I shut down
> the machines because of building poweroff. Next day when I turned them
> back on, they waited for each other forever because of the dependence.
> Eventually I had to go to single-user mode and change /etc/vfstab
> temporarily to fix it. So I wonder next time when the same poweroff
> happens, whether the machine can boot smoothly without playing
> /etc/vfstab. I know automounter is a solution, but I am also curious if
> it can be solved by changing the nfs mount options like bg | fg and soft
> | hard?
That's bg|fg rather than soft|hard and yes, in that configuration it
would be a good idea to specify bg in the vfstab.
Regards
--
Tony