Swap Space Not Activated On Boot

NoOp glgxg at sbcglobal.net
Wed Sep 3 15:38:05 UTC 2014


On 09/03/2014 06:57 AM, sktsee wrote:
> On Tue, 02 Sep 2014 19:17:24 -0700, NoOp wrote:
> 
>> On 09/02/2014 04:46 PM, sktsee wrote:
>>> On Sun, 31 Aug 2014 13:26:18 -0700, maihoaomv wrote:
>>> 
>>>> i installed  linux mint 17 xfce a month or so ago on my laptop. i
>>>> encrypted my home folder at installation but cryptswap wouldn't work
>>>> at the time. with some help from the linux mint  forum i managed to
>>>> get swap to work (most of the time). the problem i'm having now is
>>>> cryptswap doesn't always start at boot time. it worked most of the
>>>> time at first but over time it's gotten to where it almost never
>>>> starts. i have to manually start it with sudo swapon -a.
>>>> 
>>>> hopefully someone can show me what i'm doing wrong and help with solve
>>>> this problem.
>>>> thanks
>>> 
>>> [snip]
>>> 
>>> Edit the cryptswap1 entry in /etc/crypttab to identify the swap device
>>> by its device path (/dev/sda2), or by its disk by-id path (example:
>>> /dev/disk/by-id/ata-HDMANUFACTURER-MODEL-SERIALNUM-part2). If you have
>>> multiple hard disks attached to your system then use disk by-id.
>>> So your crypttab should contain a line like this:
>>> 
>>> cryptswap1   /dev/sda2    /dev/urandom 
>>> swap,cipher=aes-cbc-essiv:sha256
>>> 
>>> 
>> Read the bug reports that I posted to earlier...
> 
> I presume you're referring to this post? http://news.gmane.org/find-
> root.php?message_id=lp2a1q%249h%241%40ger.gmane.org
> 
> If so, the first bug report highlights the problems with using UUID's to 
> identify the swap device in /etc/crypttab and using the device path if 
> you have multiple disks attached to your system. This is why I suggested 
> to OP to use disk by-id as a source device. This is recommended by the 
> cryptsetup FAQ.
> 
> As to the second bug report, that's just race condition brought about 
> because of the interplay between the mountall and cryptdisks* jobs. I see 
> that error too, but once the system finishes booting I have an encrypted 
> swap present. And so far, its been persistent across boots.
> 

Sorry... specifically:
<https://bugs.launchpad.net/ubuntu/+source/cryptsetup/+bug/1153661/comments/19>
"Unfortunately, replacing UUID's by /dev/xxxx will not work if you boot
from USB. Example: I boot external usb drives and usb sticks for testing
etc. If I boot with one plugged in, the /dev/sdxx will change. See
 #953875 comments 10 & 11:

<https://bugs.launchpad.net/ubuntu/+source/ecryptfs-utils/+bug/953875/comments/10>
<https://bugs.launchpad.net/ubuntu/+source/ecryptfs-utils/+bug/953875/comments/11>"

Just having bootable usb drives connected can/will change the /dev/sdX
and so I've not been able to find a method to reliably mount encrypted
swap in this situation.






More information about the ubuntu-users mailing list