external disk weirdness

[Qqmike]

(Good, oshunluvr, I'm supposed to be gone by now, waiting on a phone call; re Post #14 IF YOU GUYS DECIDE TO FIX THE SUPPOSED BROKEN GPT ... sudo gdisk /dev/sdb, then ?, then r (= recovery and transformation options (experts only)), then d = use main GPT header (rebuilding backup) since his output said this: "Caution: invalid backup GPT header, but valid main header; regenerating backup header from main header.")

A gdisk Walkthrough

www.rodsbooks.com/gdisk/walkthrough.html

Roderick Smith

GPT fdisk Tutorial

www.rodsbooks.com/gdisk/

Roderick Smith

...

[przxqgl]

woo... so, i unplugged the drive and typed dmesg, and i got so much stuff on the screen that i can't capture it all...

then i plugged the drive in, and typed dmesg again, and this time i got pretty much the same overwhelmingly large amount of stuff, plus this:

[ 3619.241150] usb 2-2: new SuperSpeed USB device number 3 using xhci_hcd
[ 3619.258472] usb 2-2: LPM exit latency is zeroed, disabling LPM.
[ 3619.260968] usb 2-2: New USB device found, idVendor=1058, idProduct=1130
[ 3619.260976] usb 2-2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 3619.260981] usb 2-2: Product: My Book 1130
[ 3619.260985] usb 2-2: Manufacturer: Western Digital
[ 3619.260988] usb 2-2: SerialNumber: 574341575A30313830343834
[ 3619.262061] usb-storage 2-2:1.0: USB Mass Storage device detected
[ 3619.262616] scsi host9: usb-storage 2-2:1.0
[ 3621.215350] scsi 9:0:0:0: Direct-Access     WD       My Book 1130     1012 PQ: 0 ANSI: 6
[ 3621.215881] scsi 9:0:0:1: Enclosure         WD       SES Device       1012 PQ: 0 ANSI: 6
[ 3621.217165] sd 9:0:0:0: Attached scsi generic sg2 type 0
[ 3621.217528] ses 9:0:0:1: Attached Enclosure device
[ 3621.217700] ses 9:0:0:1: Attached scsi generic sg3 type 13

um... does that include a list of partitions? it certainly doesn't have the names that i'm used to...

[przxqgl]

sudo gdisk /dev/sdb, then ?, then r (= recovery and transformation options (experts only)), then d = use main GPT header (rebuilding backup)

after following Qqmike's suggestion, now, when i run dmesg again, this time i get:

[ 3619.262061] usb-storage 2-2:1.0: USB Mass Storage device detected
[ 3619.262616] scsi host9: usb-storage 2-2:1.0
[ 3621.215350] scsi 9:0:0:0: Direct-Access     WD       My Book 1130     1012 PQ: 0 ANSI: 6
[ 3621.215881] scsi 9:0:0:1: Enclosure         WD       SES Device       1012 PQ: 0 ANSI: 6
[ 3621.217165] sd 9:0:0:0: Attached scsi generic sg2 type 0
[ 3621.217528] ses 9:0:0:1: Attached Enclosure device
[ 3621.217700] ses 9:0:0:1: Attached scsi generic sg3 type 13
[ 3634.783385] sd 9:0:0:0: [sdb] 732558336 4096-byte logical blocks: (3.00 TB/2.72 TiB)
[ 3634.783618] sd 9:0:0:0: [sdb] Write Protect is off
[ 3634.783626] sd 9:0:0:0: [sdb] Mode Sense: 47 00 10 08
[ 3634.783873] sd 9:0:0:0: [sdb] No Caching mode page found
[ 3634.783879] sd 9:0:0:0: [sdb] Assuming drive cache: write through
[ 3634.784514] sd 9:0:0:0: [sdb] 732558336 4096-byte logical blocks: (3.00 TB/2.72 TiB)
[ 3634.812623] Alternate GPT is invalid, using primary GPT.
[ 3634.812658]  sdb: sdb1 sdb2 sdb3
[ 3634.813608] sd 9:0:0:0: [sdb] 732558336 4096-byte logical blocks: (3.00 TB/2.72 TiB)
[ 3634.813906] sd 9:0:0:0: [sdb] Attached SCSI disk

which looks a lot more like the partitions oshunluvr was asking for... but there's still that ominous sounding " Alternate GPT is invalid" which i don't particularly like

[Qqmike]

Still on the run (special occasion distracting me here). Follow what oshuluvr is saying about the dmesg.

Just one comment about your other comment:

sudo gdisk /dev/sdb, then ?, then r (= recovery and transformation options (experts only)), then d = use main GPT header (rebuilding backup)

When you do this (in the interactive gdisk), and are done, don't then forget to type w for write the changes before you close out and exit, right?

[przxqgl]

Still on the run (special occasion distracting me here).

i understand... don't let me hold you up. ;-)

Follow what oshuluvr is saying about the dmesg.

Just one comment about your other comment:

When you do this (in the interactive gdisk), and are done, don't then forget to type w for write the changes before you close out and exit, right?

that's the part i was missing... thanks. 8)

[przxqgl]

and, as soon as i typed w for write the changes - like magic - two new disks appeared at /media/backup and /media/home... 8)

you guys rock! 8)

now, about reformatting the disks... it's a 3TB drive, and i'm not using more than a few tens of gigabytes, at most... oshunluvr, you said something about reformatting without using a second drive to hold the stuff?

for that matter, i'm fairly sure i've got enough room on the internal drive to do that, now...

[przxqgl]

WAIT... 8(

i just rebooted, and the disks that were there so nicely are, now, nowhere to be found... even though they had nice little entries in dolphin and everything...

what went wrong... i want my disks back! 8(

[Qqmike]

To see the disks and partitions, you should also run and post for all to see, this command:

lsblk

[przxqgl]

whew!

i got my disks back... i started back at the beginning of this thread: turned off the machine, disconnected all the USB drives, and rebooted. then i ran sudo parted -l which reported the hard disk, and then i plugged in the USB disk in question and ran sudo parted -l again, although when i was in the middle of running it, two disks, once again like magic, showed up in dolphin.

i think, while i've actually got access to them, i'm going to move the data back to the internal hard disk, and reformat the drives. my impression is that it would be a lot easier if i was dealing with EXT4 disks rather than FAT32...

and, since you asked...

lsblk
NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda      8:0    0 931.5G  0 disk 
├─sda1   8:1    0 916.3G  0 part /
├─sda2   8:2    0     1K  0 part 
└─sda5   8:5    0  15.2G  0 part 
sdb      8:16   0   2.7T  0 disk 
├─sdb1   8:17   0   200M  0 part 
├─sdb2   8:18   0   1.8T  0 part /media/backup
└─sdb3   8:19   0 931.4G  0 part /media/home
sr0     11:0    1  1024M  0 rom

[oshunluvr]

Good idea to get all the data off there if you're having trouble with it. Once the data is elsewhere, I'd start with a fresh GPT table and run some stress tests on the drive. Do you know if it supports SMART?

As far as file system formats - the best choice will depend on how you plan on using the drive. ext4 won't be mac or windows compatible, which doesn't mean you can't access it from a mac or windows PC - it would just take more work.Outline your expected use-case and we'll discuss options.

[przxqgl]

Good idea to get all the data off there if you're having trouble with it. Once the data is elsewhere, I'd start with a fresh GPT table and run some stress tests on the drive. Do you know if it supports SMART?

no, i don't know if it supports SMART, but i bought it a couple of years ago, as a FAT32 formatted drive, and i took it out of the box and immediately reformatted two partitions.

As far as file system formats - the best choice will depend on how you plan on using the drive. ext4 won't be mac or windows compatible, which doesn't mean you can't access it from a mac or windows PC - it would just take more work.

it's my impression that mac will detect EXT4 the first time it experiences it, and leaves some invisible (to mac) files on the disk. windoesn't, which doesn't matter to me, since i haven't used windoesn't for 15 years.

seriously. i've never even seen a machine running 8 or 10 at all... the last version that i'm even remotely familiar with is XP...

Outline your expected use-case and we'll discuss options.

at this point i've reformatted it EXT4 and got it running with BackInTime...

but the problem is that when i reboot, it doesn't automatically mount, and doesn't even show up in dolphin until i unplug the drive, turn off the machine, turn on the machine without the drive plugged in, and then plug in the drive...

which is a hassle, and not very good for the drive, if i'm not mistaken...

presumably there's some way to make it more permanent...

[przxqgl]

so, i wiped my machine and started over. i had changed too much stuff to get my backup working the way i wanted to, so i bit the bullet and started over from scratch...

and i have been successful enough that i now have my new machine working, a newly reformatted 3TB drive, that is, in fact, working correctly with BackInTime...

it took a while, but i think it's okay now... 8)

[przxqgl]

although it still won't mount when i reboot... it doesn't even show up when i run 'sudo parted -l' until i unplug the power from the disk, and then reboot the machine... any clues for how to get that fixed? i'm assuming it's just a matter of adding a line of text to some file, but i don't remember where, or what...

[przxqgl]

here's a weird end to this whole thing... it didn't mount -- wasn't even visible when i ran 'sudo parted -l' yesterday morning, but i had to make a trip out of town, so i couldn't get to it until this morning.

i booted the machine for the first time since i determined that the disk wasn't visible, two days ago.

the disk mounted, just as though it had been doing so all along. i shut the machine down, and rebooted it several times. it showed up without me having to do anything every time.

it fixed itself...

i don't know why or how, but if it's not broke, i'm definitely not going to fix it.

[przxqgl]

okay, now that things have had the chance to settle in, i'm finding that the /backup disk (which is what the 3TB drive turned into) mounts fine when i boot up for the first time in the morning, but if i have to reboot for any reason, i have to completely shut down and start it up again, from power off, because if i reboot the machine without turning the power off, when it is finished rebooting, the /backup disk isn't there.

any clue how i can fix this? my impression is that it's a matter of adding a line of text to a settings file, but i'm not sure what or where...