"glabel label" questions

[Scott Bennett]

     On Mon, 11 Jan 2010 12:24:47 +0000 krad <kraduk at googlemail.com> wrote:
>2010/1/11 Scott Bennett <bennett at cs.niu.edu>
>
>>     My system currently has three external disk drives connected via USB
>> 2.0
>> ports and will soon have another drive connected via a Firewire port.  The
>> three already present have quite a few partitions on them, nearly all of
>> which
>> already contain file systems with lots of files in them.  I would like to
>> use
>> the "glabel label" method of labeling each of these partitions, so that I
>> do
>> not always have to disconnect all but one external drive when rebooting the
>> system and then reconnect them one by one in order to get the proper device
>> files assigned to them for use with /etc/fstab entries.
>>     However, some of these partitions contain GELI-encrypted file systems.
>> Can the "glabel label" sort of labeling be used with encrypted partitions?
>> If so, can "glabel label" be used on the encrypted partitions without
>> destroying the file systems or the data in them?  Or will I need to
>> recreate
>> the file systems after labeling the partitions and then restore their
>> contents
>> from backups?  Is there any danger to unencrypted partitions and data when
>> using the "glabel label" operation?
>>     Thanks in advance for any help with this matter.
>>
>
>just unmount them and do a tunefs -L <name> <device> on them. Geli works a
>layer below the fs so should work fine.
>
     Thank you for responding.  Unfortunately, it appears I didn't state my
questions clearly enough.
     The layering of the software is not what concerns me most here.  What
worries me is whether writing the label information to the disk will overwrite
my data or file system control structure data that are already present on the
disk.
     The layering issue that does concern me, however, is not that GELI
lies below the file system, which one can clearly see even from the
instructions in the handbook for setting up GELI-encrypted partitions.  What
is at issue is whether GELI can properly handle /dev/label/somename as a
provider for a "geli attach" operation, creating then a /dev/label/somename.eli
device file that can then be mounted onto a directory in the file system.


                                  Scott Bennett, Comm. ASMELG, CFIAG
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