The only time I've used gpt with linux was with a efi-boot-only laptop, but prior I can raid the boot sector drive still with software and not have to use fakeraid at all for full partition redundancy. Still kind of a new concept for a lot of people I think. Ubuntu otherwise happily still uses mbr, so was a bit of a curve for me to have to adapt as they don't bake their gpt or raid tools well in the initrd or install.

If you raided your /boot and *other* raid volume, I'd say just redo the partitions with gdisk and resync the raid which is pretty easy (I have to do this somewhat commonly with my ssd's). I can run swap and root from lvm on the raid otherwise for full redundancy and easy disk rebuilds if/when needed. That keeps failure recovery very easy. Only EFI complicates this with crappy non-raidable fat32 partitions needed now (eww, thanks microsoft).

My gpt/efi laptop looks much the same with dual ssd's, but has the first partition as an identical fat32 partition on each to satiate ubuntu as /boot/EFI and /bootEFI1, plus a mdraided /boot second, and crypt volume third. If not adding encryption, lvm atop the mdraid pv for a lot more flexibility in volume/redundancy restoration among disks. I just rsync the stupid efi fat32 disks.

mb@host:~$ lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sdh 8:112 0 111.8G 0 disk
├─sdh1 8:113 0 100M 0 part
│ └─md127 9:127 0 100M 0 raid1 /boot
└─sdh2 8:114 0 111.7G 0 part
└─md126 9:126 0 111.7G 0 raid1
└─spv0 (dm-0) 252:0 0 111.7G 0 crypt
├─vg0-root (dm-1) 252:1 0 2G 0 lvm /
├─vg0-swap (dm-2) 252:2 0 2G 0 lvm [SWAP]
├─vg0-var (dm-3) 252:3 0 2.5G 0 lvm /var
├─vg0-usr (dm-4) 252:4 0 10G 0 lvm /usr
├─vg0-home (dm-5) 252:5 0 32G 0 lvm /home
sdi 8:128 0 111.8G 0 disk
├─sdi1 8:129 0 100M 0 part
│ └─md127 9:127 0 100M 0 raid1 /boot
└─sdi2 8:130 0 111.7G 0 part
└─md126 9:126 0 111.7G 0 raid1
└─spv0 (dm-0) 252:0 0 111.7G 0 crypt
├─vg0-root (dm-1) 252:1 0 2G 0 lvm /
├─vg0-swap (dm-2) 252:2 0 2G 0 lvm [SWAP]
├─vg0-var (dm-3) 252:3 0 2.5G 0 lvm /var
├─vg0-usr (dm-4) 252:4 0 10G 0 lvm /usr
├─vg0-home (dm-5) 252:5 0 32G 0 lvm /home

-mb



On 02/02/2014 08:44 PM, George Toft wrote:
installed gdisk and it looks like /dev/sdb is damaged, but /dev/sdc is good :) doing a dd on the whole drive to a file on another drive so I have a backup. I'll check back in a couple days when it's done.

Regards,

George Toft

On 2/2/2014 2:58 PM, Matt Graham wrote:
# fdisk -l | egrep "GPT|dev"
WARNING: fdisk doesn't support GPT.
/dev/sdb1 1 267350 2147483647+ ee GPT

# mdadm --assemble --run /dev/md0 /dev/sdb1
mdadm: cannot open device /dev/sdb1: No such
file or directory

This is an odd message to get, and probably means that udev didn't find the device and create it because udev and/or the rescue system's GPT support is flaking out. Does the kernel in this rescue system support GPT? "mknod /dev/sdb1 b 8 17" to create it. You may wish to "mknod /dev/sdc1 8 33" in case the other softRAID-1 disk has better stuff on it.

As other people have said, there should be no need to use mdadm to assemble an array out of RAID-1 partitions. "mount /dev/sdb1 /mnt/somewhere" should do something useful if the device node and /mnt/somewhere exist.

On 2014-02-02 12:57, Michael Butash wrote:
Use gdisk if/when doing gpt

That too. (One day, we will forsake our filesystems and break all bonds of block devices to get a disk larger than 2T for actual experience with GPT, but today is *not* this day. This day, we *SOLVE TECH PROBLEMS!!!1!*)


---------------------------------------------------
PLUG-discuss mailing list - [email protected]
To subscribe, unsubscribe, or to change your mail settings:
http://lists.phxlinux.org/mailman/listinfo/plug-discuss

---------------------------------------------------
PLUG-discuss mailing list - [email protected]
To subscribe, unsubscribe, or to change your mail settings:
http://lists.phxlinux.org/mailman/listinfo/plug-discuss

Reply via email to