Re: New Grub2 verses Debian 9.5 -boots slow and strange?

[jmh6]

On Sun, 21 Oct 2018, Pascal Hambourg wrote:

> Le 21/10/2018 ? 01:11, address@hidden a ?crit :
> > On Sat, 20 Oct 2018, Pascal Hambourg wrote:
> > > No swap indeed. But there are two unformatted partitions (or with 
> > > unknown format). Intriguing. Can you check with
> > >
> > > file -s /dev/sda2 /dev/sdb5
> > > wipefs /dev/sda2
> > > wipefs /dev/sdb5
> > >
> > > > address@hidden:/etc/initramfs-tools/conf.d# cat resume
> > > > RESUME=UUID=b66a9345-332d-4abf-a081-351ab08ed7f9
> > >
> > > So there once was a swap with this UUID. But it cannot be found any 
> > > more. Maybe /etc/fstab still contains information about it.
> > >
> > > You have basically two options :
> > > - remove the swap references in resume and fstab and run 
> > > update-initramfs -u
> > > - or recreate a swap with the same UUID in sdb5
> >
> > Hi Pascal,
> >
> > I am nervous about running wipefs. Especially since its man page does 
> > not match is operation. plain wipefs doesn't show anything while the 
> > manpage says it should.
>
> Dont worry about wipefs : without -o or -a, it does not erase anything 
> and just looks for metadata signatures. Sometimes it is better than file 
> at finding signatures.
>
> > file -s thinks the swap partitions are data?
>
> Meaning that it found nothing.
>
> >    fdisk thinks there are swap partitions.
>
> fdisk displays the partition type identifier recorded in the partition 
> table, which does not have to match the actual partition contents. But 
> then we can assume they are swap partitions which should be formatted as 
> swap.
>
> > Device     Boot    Start      End  Sectors  Size Id Type
> > /dev/sdb5       19840338 30700214 10859877  5.2G 82 Linux swap / Solaris
> (...)
> > Device     Boot     Start       End   Sectors  Size Id Type
> > /dev/sda2       838862848 843057151   4194304    2G 82 Linux swap / Solaris
>
> As I suggested, if you want to use sdb5 as swap you can format it with 
> the UUID present in /etc/initramfs-tools/conf.d/resume :
>
> mkswap --uuid b66a9345-332d-4abf-a081-351ab08ed7f9 /dev/sdb5
>
> Did you check if /etc/fstab contains any references to swap partitions ?

Hi Pascal,

  Good points. I somehow missed the whole UUID thing?? From what I 
understand UUID is 'somehow' stored in the 'master block' of the 
partition? I assume this really means the first physical block of the 
partition as opposed to the MBR?

   fstab is printed below.

   fstab seems to 'know' about the HUGE swap partition. Quite a waste of 
space! I am tempted to use fdisk and tweak things and see if Debian 9.5 
can figure it out. As long as I remember to put down the original values I 
'should' be able to put things back :) ?

   I gather wipefs tries to locate the UUID and 'fix' it?

   I am still trying to fully comprehend what you have kindly written. I 
gather that if I get the UUID correct, my 'can't find the disk' delays 
will likely become much shorter or disappear.

   I will at this point go back over what you have already written.

   Questions will doubtless follow :) :).

   I am amazed to we have more or less fixed this SD so it boots :).

   Thanks again.

   warm regards,
   John


-------------------------------------------------
address@hidden:~/Desktop# cat /etc/fstab
# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
# / was on /dev/sdc1 during installation
UUID=342345d7-94fa-42d2-ae4c-8e947418fd32 /               ext4 
errors=remount-ro 0       1
# swap was on /dev/sdc5 during installation
UUID=b66a9345-332d-4abf-a081-351ab08ed7f9 none            swap    sw 
0       0
/dev/sr0        /media/cdrom0   udf,iso9660 user,noauto     0       0
address@hidden:~/Desktop# 
-------------------------------------------------

> Also, I assume that sda2 was used by the system installed on sda and 
> maybe this system also misses its swap partition ?
>
> _______________________________________________
> Help-grub mailing list
> address@hidden
> https://lists.gnu.org/mailman/listinfo/help-grub