Post new topic   Reply to topic
View previous topic Printable version Log in to check your private messages View next topic
Author Message
Luis_POffline
Post subject: Weird behavior of uuid  PostPosted: 23.03.2013, 22:12



Joined: 2010-09-11
Posts: 152
Location: Barcelona, Spain
Status: Offline
I've realized that the uuid code of my two HD aren't the same on different boots. Here are the contents of /dev/disk/by-uuid in 2 moments of today:

This morning:
      Code:

lrwxrwxrwx 1 root root 10 mar 23 10:25 122c0f1c-9f47-475b-b460-2d6188b0c440 -> ../../sda2
lrwxrwxrwx 1 root root 10 mar 23 10:25 17405d87-e0a8-4b36-94cd-27682c750d50 -> ../../sda3
lrwxrwxrwx 1 root root 10 mar 23 10:25 41809959-28b0-449b-9deb-e1495e2b742e -> ../../sdb3
lrwxrwxrwx 1 root root 10 mar 23 10:26 91436a3a-1b66-45f9-8e50-4be8e3b4fd4f -> ../../sdb2
lrwxrwxrwx 1 root root 10 mar 23 10:25 9c20d769-2927-4bcd-bb03-73c5c384b6b2 -> ../../sdb1
lrwxrwxrwx 1 root root 10 mar 23 10:25 a29f44f5-75aa-48f8-90ad-2dc8ee1c4fb7 -> ../../sdb4
lrwxrwxrwx 1 root root 10 mar 23 10:26 d1e46756-9e15-48e1-964e-3cd1b8263f71 -> ../../sda1


This night:
      Code:

lrwxrwxrwx 1 root root 10 mar 23 22:13 122c0f1c-9f47-475b-b460-2d6188b0c440 -> ../../sdb2
lrwxrwxrwx 1 root root 10 mar 23 22:13 17405d87-e0a8-4b36-94cd-27682c750d50 -> ../../sdb3
lrwxrwxrwx 1 root root 10 mar 23 22:13 41809959-28b0-449b-9deb-e1495e2b742e -> ../../sda3
lrwxrwxrwx 1 root root 10 mar 23 22:13 91436a3a-1b66-45f9-8e50-4be8e3b4fd4f -> ../../sda2
lrwxrwxrwx 1 root root 10 mar 23 22:13 9c20d769-2927-4bcd-bb03-73c5c384b6b2 -> ../../sda1
lrwxrwxrwx 1 root root 10 mar 23 22:13 a29f44f5-75aa-48f8-90ad-2dc8ee1c4fb7 -> ../../sda4
lrwxrwxrwx 1 root root 10 mar 23 22:13 d1e46756-9e15-48e1-964e-3cd1b8263f71 -> ../../sdb1


As you can see, the sda... disk has turned into sdb... and vice-versa. It could be only a curiosity if it does not complicate a lot the administration of the system.

Any advice will be very appreciated.

Regards.

Luis_P.
 
 View user's profile Send private message  
Reply with quote Back to top
finottiOffline
Post subject: RE: Weird behavior of uuid  PostPosted: 23.03.2013, 23:07



Joined: 2010-09-12
Posts: 325

Status: Offline
I am not an expert, but if I remember well, that is exactly the point of using UUID, as sometimes the order in which HDs a recognized can change.
 
 View user's profile Send private message  
Reply with quote Back to top
slhOffline
Post subject: RE: Weird behavior of uuid  PostPosted: 23.03.2013, 23:39



Joined: 2010-08-25
Posts: 760

Status: Offline
Device detection order is (semi-)random. depending on the exact timing they're discovered during the boot/ or plug cycle; device enumeration differs accordingly, the only stable mapping is based on additional udev criterias (like UUIDs).
 
 View user's profile Send private message  
Reply with quote Back to top
Luis_POffline
Post subject:   PostPosted: 24.03.2013, 13:07



Joined: 2010-09-11
Posts: 152
Location: Barcelona, Spain
Status: Offline
      Quote:
Device detection order is (semi-)random


It's a pity that not be in man pages (I've been not able to find) or, better, in our manual, which speaks about "Persistent Naming by LABEL". Because that, I've lost some archives.

Thanks for your support.

Luis_P.
 
 View user's profile Send private message  
Reply with quote Back to top
Luis_POffline
Post subject:   PostPosted: 25.03.2013, 17:16



Joined: 2010-09-11
Posts: 152
Location: Barcelona, Spain
Status: Offline
More on this topic.

I suppose this randomness exists also for others file systems. I'm talking about the grub2 filesystem (hd0...). If so, booting with grub2 other OS is accident-prone.

The supposition arises from the fact that as a consequence of an aptosid dist-upgrade, I cannot boot my second OS (Salix, a Slackware derivative).

Luis_P.
 
 View user's profile Send private message  
Reply with quote Back to top
Display posts from previous:     
Jump to:  
All times are GMT - 12 Hours
Post new topic   Reply to topic
View previous topic Printable version Log in to check your private messages View next topic
Powered by Zafenio