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Re: Corel/Debian Linux Installer



>> > /etc  -- small, 16-32MB, mounted read-write, 0% reserve
>> 
>> You cannot have /etc on a seperate partition - how will you change files used
>> on / before it's mounted, eg /etc/fstab?
>
>Ack.  You're right.  The same thing applies to /dev.  I guess the root
>filesystem (for all practical purposes) _has_ to be mounted read-write. 
>Syslog opens a file in /dev and anyone wanting raw access to anything in
>/dev would probably have trouble as well.  I don't want to create a slew
>of partitions for the sake of doing so, but I think it would be ideal if
>it were possible to never fsck / after a crash.  This may not be so.

Opening device files on a read-only file system works well for me.  I've just
mounted a file system read-only, see this:
rjc@lyta:/usr/src$touch foo
touch: foo: Read-only file system
rjc@lyta:/usr/src$ls -l null
crw-rw-rw-   1 root     sys        1,   3 Aug  1  1997 null
rjc@lyta:/usr/src$cat /etc/passwd > null
rjc@lyta:/usr/src$

Seems that read-only file systems only apply to real files.  I have only tested
this with ReiserFS, but I believe that it's all VFS functionality and should
work in all file systems.  If it doesn't then that's a kernel bug.
/dev can be mounted read-only if you don't need/want to change permissions etc.

For /etc, the fstab file is not a problem.  mtab could be an issue, but it
could be a sym-link pointing elsewhere (so you re-mount root with the "-n"
option).  If you use a service such as LDAP for authentication then you only
need an entry for root in /etc/passwd (and probably other system accounts). 
User accounts don't need it.  Of course changing the root password would be a
real PITA!

>To append to another message I just sent, I also like /var being by itself
>for logfiles.  In case all the other partitions fill you aren't left not
>knowing what's happening (assuming of course you give yourself enough
>size).

Alternatively if a daemon goes into an infinite loop writing error messages
(seen this happen with an old version of cfingerd and also with a commercial
LDAP server) then you don't want it to remove all space from /home, /database,
etc...

-- 
My contract ends next week.  I'd be happy to do a week's work in the US for
a round-trip air-fare and all expenses.


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