Gentoo Archives: gentoo-user

From: Dale <rdalek1967@×××××.com>
To: Gentoo User <gentoo-user@l.g.o>, Ramon_Fischer@×××××××.de
Subject: Re: [gentoo-user] cryptsetup close and device in use when it is not
Date: Wed, 07 Jul 2021 18:09:06
Message-Id: 5483630c-3cd1-bca2-0a6d-62bb85a5adc6@gmail.com
In Reply to: Re: [gentoo-user] cryptsetup close and device in use when it is not by Dr Rainer Woitok
1 Dr Rainer Woitok wrote:
2 > Ramon, Dale,
3 >
4 > On Tuesday, 2021-07-06 20:40:32 +0200, Ramon Fischer wrote:
5 >
6 >> This is just a guess. Maybe you have two devices with the same UUID?
7 >>
8 >> If so, you can change it with:
9 >>
10 >> $ cryptsetup --uuid="<some_uuid>" luksUUID "/dev/sdx1"
11 > Good idea. But to find out whether or not this is the cause of Dale's
12 > problems I would suggest to first run "cryptsetup" without the "--uuid"
13 > option (in order to get the UUID listed) and to then compare this with
14 > the output from "ls /dev/disk/by-uuid".
15 >
16 > Sincerely,
17 > Rainer
18 >
19
20
21 Well, it's midweek and I wanted to test this theory even tho it is
22 early.  Plus, it's raining outside so I'm a bit bored.  I pulled the
23 backup drive from the safe and did a backup.  While it was backing up
24 new stuff, I ran this:
25
26
27 root@fireball / # blkid | grep dde669
28 /dev/mapper/8tb: LABEL="8tb-backup"
29 UUID="0277ff1b-2d7c-451c-ae94-f20f42dde669" BLOCK_SIZE="4096" TYPE="ext4"
30 root@fireball / # ls /dev/disk/by-uuid | grep dde669
31 0277ff1b-2d7c-451c-ae94-f20f42dde669
32 root@fireball / #
33
34
35 I just grepped the last little bit of the UUID to see if anything else
36 matched.  It didn't.  I tried both methods just in case.  It was
37 grasping at straws a bit but hey, sometimes that straw solves the
38 problem.  I might add, I unmounted the drive and cryptsetup closed it
39 first time with not a single error.  It didn't even burp.  Given I've
40 done this several times with no problem after doing the UUID way with
41 consistent errors, I think it is safe to assume that changing from UUID
42 to labels solves this problem.  The question now is this, why?  It's not
43 like one mounts something different or anything.  It's the same device,
44 just using a different link basically. 
45
46 This is thoroughly confusing.  It just doesn't make sense at all. 
47 Either way should work exactly the same. 
48
49 I'm open to ideas on this.  Anybody have one?  I'll test it if I can
50 even if it is a serious grasp at a small straw.  ;-)
51
52 Dale
53
54 :-)  :-) 

Replies

Subject Author
Re: [gentoo-user] cryptsetup close and device in use when it is not Ramon Fischer <Ramon_Fischer@×××××××.de>
Re: [gentoo-user] cryptsetup close and device in use when it is not Frank Steinmetzger <Warp_7@×××.de>