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Date: Mon,  7 Aug 95 15:17:32 +0000
Content-Identifier: Re: patch adding
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To: freebsd-hackers@freebsd.org
Subject: Re: patch adding the 'noauto' switch to 'mount'
Sender: hackers-owner@freebsd.org
Precedence: bulk

>>I just got fed up with my DOS partition being mounted automatically
>>at boot time, so I wrote a patch which enables the use of the 'noauto'
>>flag in /etc/fstab.
>>
>>For example:    /dev/sd0s2              /dos    msdos rw,noauto 0 0
>>
>>This flag prevents a filesystem from being mounted when a 'mount -a' occurs.
>>It works for every kind of fs , since it's defined as a standard
>>mount option.
>
>   That's an interesting option, but the "-a" switch stands for "all" - not
>"auto". I suppose the first question that comes to mind is: if you don't want
>the filesystem mounted with "-a", then why are you putting it in fstab?

This reminds me of a problem that I have been having since upgrading to 2.0.5
(actually I did a re-format and clean install).  The install left me with an
fstab entry for /cdrom which is fine.  However, if I should happen to re-boot
with an audio CD in the drive, I now get thrown into single-user mode and can't
proceed without either supplying a real CD-ROM or commenting out the entry in
fstab.  Under 2.0 and 9503xx-SNAP, this didn't happen - I just got a rude
message and the boot proceeds as normal.  Having the entry in fstab was handy in
that it auto-mounted the CD if one happened to be in the drive, and if not it
still allowed an abbreviated command to mount manually -  "mount /cdrom".  I
haven't yet pulled back my old configuration off tape to see if I have
inadvertenly changed somthing else that might affect this behaviour. 

One answer to your question 'why would you want entries in /etc/fstab" that you
don't want mounted by mount -a' is so that you can later do a manual mount with
"mount /dos" or similar, without having to remember the slice number etc.
(admittedly not too hard to remember in the case of the /dev/cd0).