On 08/30/2018 07:08 PM, Chris Murphy wrote:
On Thu, Aug 30, 2018 at 3:13 AM, Pierre Couderc <pie...@couderc.eu> wrote:
Trying to install a RAID1 on a debian stretch, I made some mistake and got
this, after installing on disk1 and trying to add second disk :
root@server:~# fdisk -l
Disk /dev/sda: 1.8 TiB, 2000398934016 bytes, 3907029168 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x2a799300
Device Boot Start End Sectors Size Id Type
/dev/sda1 * 2048 3907028991 3907026944 1.8T 83 Linux
Disk /dev/sdb: 1.8 TiB, 2000398934016 bytes, 3907029168 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x9770f6fa
Device Boot Start End Sectors Size Id Type
/dev/sdb1 * 2048 3907029167 3907027120 1.8T 5 Extended
Extended partition type is not a problem if you're using GRUB as the
bootloader; other bootloaders may not like this. Strictly speaking the
type code 0x05 is incorrect, GRUB ignores type code, as does the
kernel. GRUB also ignores the active bit (boot flag).
And :
root@server:~# btrfs fi show
Label: none uuid: eed65d24-6501-4991-94bd-6c3baf2af1ed
Total devices 2 FS bytes used 1.10GiB
devid 1 size 1.82TiB used 4.02GiB path /dev/sda1
devid 2 size 1.00KiB used 0.00B path /dev/sdb1
That's odd; and I know you've moved on from this problem but I would
have liked to see the super for /dev/sdb1 and also the installer log
for what commands were used for partitioning, including mkfs and
device add commands.
For what it's worth, 'btrfs dev add' formats the device being added,
it does not need to be formatted in advance, and also it resizes the
file system properly.
Thank you, in fact my system seems more and more broken, so I cannot go
further..
For example, a simple
df gives me an IO error.
I prefer reinstall the whole.
But to avoid the same problems, is there somewhere an howto "install a
basic RAID1 btrfs debian stretch system" ?
OK, I install strech on 1 disk and then how do I "format" and add the
second disk ?
My purpose is a simple RAID1 main fs, with bootable flag on the 2 disks in
prder to start in degraded mode....
Good luck with this. The Btrfs archives are full of various
limitations of Btrfs raid1. There is no automatic degraded mount for
Btrfs. And if you persistently ask for degraded mount, you run the
risk of other problems if there's merely a delayed discovery of one of
the devices. Once a Btrfs volume is degraded, it does not
automatically resume normal operation just because the formerly
missing device becomes available.
So... this is flat out not suitable for use cases where you need
unattended raid1 degraded boot.
Well, I understnad the lesson that there is no hope currently to boot
a degraded system...
Thank you very much
