Dashboard opens with blank only

[fvdw]

You need to view it with an hex editor.
I do not know if it contains useful info but it seems the darray is readable.
Instead of using putty you could try to copy it to your pc using a program like winscp.

[fariaslcfs]

You need to view it with an hex editor.
I do not know if it contains useful info but it seems the darray is readable.
Instead of using putty you could try to copy it to your pc using a program like winscp.

(uff!) After some work, it follows the respective .htm file of the image (attached).

[Jocko]

Hi

I read some previous posts and I noticed the raid age is very recent (small value of events index). Did you try to set a new raid ? In this case, you have destroyed your data.

[fvdw]

@jocko, which post do you refer to ?

The hex output seems to contain some useful information
The superblock is empty, the first four bytes should be 58 46 53 42 (=XFSB)
This confirms the reason why array cannot be mounted and why superblock has a bad magic number.

However from hex address 0x10000 onwards you can see inodes every 0x200 (=512) bytes until hex address 0x13F00

Code: Select all

00010000  49 4E 41 ED 02 01 00 00 00 00 00 00 00 00 00 00  INAí............
00010010  00 00 00 02 00 00 00 00 00 00 00 00 00 00 00 00  ................
00010020  00 00 1F B9 10 9C 32 80 00 00 1F B9 10 9C 32 80  ...¹.œ2€...¹.œ2€
00010030  00 00 1F B9 10 9C 32 80 00 00 00 00 00 00 00 06  ...¹.œ2€........
00010040  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00010050  00 00 00 02 00 00 00 00 00 00 00 00 00 00 00 00  ................
00010060  FF FF FF FF 00 00 00 00 08 00 00 00 00 00 00 00  ÿÿÿÿ............
00010070  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00010080  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00010090  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000100A0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000100B0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000100C0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000100D0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000100E0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000100F0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00010100  49 4E 80 00 02 02 00 00 00 00 00 00 00 00 00 00  IN€.............
00010110  00 00 00 01 00 00 00 00 00 00 00 00 00 00 00 00  ................
00010120  00 00 00 00 00 00 00 00 00 00 1F B9 10 9D A5 98  ...........¹..¥˜
00010130  00 00 1F B9 10 9D A5 98 00 00 00 00 00 00 00 00  ...¹..¥˜........
00010140  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00010150  00 00 00 02 00 00 00 00 00 00 00 04 00 00 00 00  ................
00010160  FF FF FF FF 00 00 00 00 00 00 00 00 00 00 00 00  ÿÿÿÿ............
00010170  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00010180  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00010190  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000101A0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000101B0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000101C0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000101D0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000101E0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000101F0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00010200  49 4E 80 00 02 02 00 00 00 00 00 00 00 00 00 00  IN€.............
00010210  00 00 00 01 00 00 00 00 00 00 00 00 00 00 00 00  ................
00010220  00 00 1F B9 10 9E 12 F8 00 00 1F B9 10 9E 12 F8  ...¹.ž.ø...¹.ž.ø
00010230  00 00 1F B9 10 9E 12 F8 00 00 00 00 00 00 00 00  ...¹.ž.ø........
00010240  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00010250  00 00 00 02 00 00 00 00 00 00 00 00 00 00 00 00  ................
00010260  FF FF FF FF 00 00 00 00 00 00 00 00 00 00 00 00  ÿÿÿÿ............
00010270  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00010280  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00010290  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000102A0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000102B0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000102C0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000102D0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000102E0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
000102F0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
00010300  49 4E 00 00 02 00 00 00 00 00 00 00 00 00 00 00  IN..............

Most inodes seems to be empty but some contain file info.

Why the inodes are not beyond hex address 0x13F00 may be because it is empty space, remember we only copie 512 kB

I do not know what it means but it might be worth to try to copy a bigger part of the array to see if we can locate another superblock. If we can find that we could try to write it to the first bytes of the array to repair the file system Need to do some reading how much we need to copy to find another superblock

[fvdw]

This info from mkfs.xfs -N /dev/md4 gives the info needed

Code: Select all

meta-data=/dev/md4               isize=256    agcount=32, agsize=60980400 blks
         =                       sectsz=4096  attr=2
data     =                       bsize=4096   blocks=1951372672, imaxpct=5

A superblock can be found at beginning of each ag.

We have 32 ag's each wth size of 60980400 blocks of 4096 bytes.
If you multiply that you get a size of 7.992.822.988.800 bytes (which corresponds with the size of your array.
So we should have 31 superblock backups and the backup superblocks should be present at each 60980400*4096 bytes = 249.775.718.400 bytes (= 232 GB)

Lets try to find one and check content

Code: Select all

dd if=/dev/md4 of=md4-2.img bs=4096 skip=60980399 count=256

this is the structure of an xfs file system
Besides the superblock also the next essential blocks (descriptors, free lists seems to be empty...

xfs-structure.JPG

[Jocko]

You can find this information when mdadm examines the raid members :

Code: Select all

    Update Time : Thu Jan  1 00:32:17 1970
       Checksum : 40736bf0 - correct
         Events : 16

So the value 16 is very low and we should expect a biggest value after a long time usage

https://plugout.net/viewtopic.php?f=26&t=3472#p34860

[fvdw]

You can find this information when mdadm examines the raid members :

Code: Select all

    Update Time : Thu Jan  1 00:32:17 1970
       Checksum : 40736bf0 - correct
         Events : 16

So the value 16 is very low and we should expect a biggest value after a long time usage

https://plugout.net/viewtopic.php?f=26&t=3472#p34860

You might be right, because so to see there is no xfs file system on this array, not only superblock is missing but the next 4 essiential blocks as well.

But lets see what the output from copying the beginning of the second ag block brings....

[fariaslcfs]

Hi

I read some previous posts and I noticed the raid age is very recent (small value of events index). Did you try to set a new raid ? In this case, you have destroyed your data.

That's possible, but I'm not sure.
Me and other colleague were trying to recover the raid without success.
So, we come back to this forum in order to find counseling.

[fariaslcfs]

Lets try to find one and check content

Code: Select all

dd if=/dev/md4 of=md4-2.img bs=4096 skip=60980399 count=256

this is the structure of an xfs file system
Besides the superblock also the next essential blocks (descriptors, free lists seems to be empty...

$matches[2]

See the attached file:

[fvdw]

Not good, it contains only zero's, so empty, assuming you have executed the command correctly and this is really the place were an AG should start according my guess , then it means in combination with the fact that first 64 kB of the array also only contains zero's it seems that there is no xfs file system on this array is my conclusion. I did a check by creating on xfs file system on one of my disks and doing the same exercise. I found the expected data in beginning of the disk img and at location of second ag block. of course you could try for the third ag block but I guess it will be empty as well.

The fact that the first 64kB are empty as well is an indication that you or your colleague have recreate the array and destroyed the data on it (chunk size used 64 kB) and that there is no xfs file system on the new array.

@jocko on an raid array without file system can you then still run a sync to add a disk (see one of his first post were one member was not active and loater added )

If Jocko confirms that syncing can be done on an array without file system then I am very sorry but it seems to be the end of this story and that your data is lost.
Hopefully you have a back up of the data.