Re: union mounts, mfs, and newsyslog

[matthew sporleder <msporleder%gmail.com@localhost>]

2009/7/8 Zafer AydoÄan <zafer%aydogan.de@localhost>:
> On Wed, Jul 8, 2009 at 3:42 AM, matthew 
> sporleder<msporleder%gmail.com@localhost> wrote:
>> On Tue, Jul 7, 2009 at 9:11 PM, David
>> Holland<dholland-current%netbsd.org@localhost> wrote:
>>> On Tue, Jul 07, 2009 at 06:54:52AM -0400, matthew sporleder wrote:
>>> Â> > I think the idea was to use a union mount instead of using unionfs,
>>> Â> > although the cited line doesn't do that; you'd want
>>> Â> >
>>> Â> > Â Â mount -t mfs -o union swap /var/log
>>> Â> >
>>> Â> > This isn't the same thing, but it may serve your purposes if you don't
>>> Â> > need the union to extend over subdirs.
>>> Â>
>>> Â> Oh, okay. ÂI read the mount(8) man page a few times and still didn't
>>> Â> really get what it was saying until now.
>>>
>>> Any suggestions for improving it? :-/
>>>
>>
>> I always have suggestions and opinions. Â:)
>>
>> Just add the example you gave me with a description like:
>> "
>> mount -t mfs -o union swap /var/log
>>
>> Creates an mfs mount on top of /var/log from the swap partition. ÂThis
>> example does not descend into subdirectories. ÂSee mount_union(8) for
>> more information on union mounts.
>> "
>>
>> (patch below)
>>
>> --- mount.8.orig    Â2009-07-07 21:54:21.000000000 -0400
>> +++ mount.8 Â Â 2009-07-07 22:01:34.000000000 -0400
>> @@ -466,6 +466,20 @@
>> Âfile system format in the first
>> Â.Tn CD-ROM
>> Âdrive.
>> +.Pp
>> +.Dl mount -t mfs -o union swap /var/log
>> +.Ed
>> +.Pp
>> +Creates an
>> +.Pa mfs
>> +mount on top of
>> +.Pa /var/log
>> +from the
>> +.Pa swap
>> +partition. ÂThis example does not descend into
>> +subdirectories. ÂSee mount_union(8) for more
>> +information on union mounts.
>> +
>> Â.Sh DIAGNOSTICS
>> ÂThe error
>> Â.Dq Operation not supported by device
>>
>
> fyi:
> this way you can use tmpfs over union. this is the only way to get
> tmpfs over union working. i'm using this since a while. it isn't
> documented anywhere.
>

Sounds like a good addition to the tmpfs man page.  :)