[ovirt-users] Re: Data recovery from (now unused, but still mounted) Gluster Volume for a single VM

2021-08-06 Thread Strahil Nikolov via Users
Hi David,
I hope you manage to recover the VM or most of the data. If you got multiple 
disks in that VM (easily observeable in oVirt UI), you might need to repeat 
that again for the rest of the disks.
Check with xfs_info the inode size (isize), as the default used to be 256, but 
I have noticed that in some cases mkfs.xfs picked a higher value (EL7). Also, 
check the gluster's logs or at least keep them for a later check. Usually, 
smaller inode size can cause a lot and really awkward issues in Gluster, but 
this needs to be verified.
Once the raid is fully rebuilt, you will have to add both the HW raid and the 
arbiter brick (add-brick replica 3 arbiter 1) . As you will be reusing the 
arbiter brick, the safest is to mkfs.xfs and also increase the inode ratio to 
90%.
Can you provide your volume info ? The default shard size is just 64MB and 
transfer is quite fast, so there should be no locking or the symptoms reported .
Once the healing is over, you should be ready for the rebuilt of the other node.
Best Regards,Strahil Nikolov


Ok, so right now, my production cluster is operating off of a single brick. I 
was planning on expanding the storage on the 2nd host next week, and adding 
that back into the cluster, and getting the Replica 2, Arbiter 1 redundancy 
working again.

How would you recommend I proceed with that plan, knowing that I'm currently 
operating off of a single brick in which I did NOT specify the size with 
`mkfs.xfs -i size=512?
Should I specify the size on the new brick I build next week, and then once 
everything is healed, reformat the current brick?

> And then there is a lot of information missing between the lines: I guess you 
> are using a 3 node HCI setup and were adding new disks (/dev/sdb) on all 
> three nodes and trying to move the glusterfs to those new bigger disks?

You are correct in that I'm using 3-node HCI. I originally built HCI with 
Gluster replication on all 3 nodes (Replica 3). As I'm increasing the storage, 
I'm also moving to an architecture of Replica 2/Arbiter 1. So yes, the plan was:

1) Convert FROM Replica 3 TO replica 2/arbiter 1
2) Convert again down to a Replica 1 (so no replication... just operating 
storage on a single host)
3) Rebuild the RAID array (with larger storage) on one of the unused hosts, and 
rebuild the gluster bricks
4) Add the larger RAID back into gluster, let it heal
5) Now, remove the bricks from the host with the smaller storage -- THIS is 
where things went awry, and what caused the data loss on this 1 particular VM
--- This is where I am currently ---
6) Rebuild the RAID array on the remaining host that is now unused (This is 
what I am / was planning to do next week)




Sent with ProtonMail Secure Email.

‐‐‐ Original Message ‐‐‐

On Thursday, August 5th, 2021 at 3:12 PM, Thomas Hoberg  
wrote:

> If you manage to export the disk image via the GUI, the result should be a 
> qcow2 format file, which you can mount/attach to anything Linux (well, if the 
> VM was Linux... it didn't say)
> 

> But it's perhaps easier to simply try to attach the disk of the failed VM as 
> a secondary to a live VM to recover the data.
> 

> Users mailing list -- users@ovirt.org
> 

> To unsubscribe send an email to users-le...@ovirt.org
> 

> Privacy Statement: https://www.ovirt.org/privacy-policy.html
> 

> oVirt Code of Conduct: 
> https://www.ovirt.org/community/about/community-guidelines/
> 

> List Archives: 
> https://lists.ovirt.org/archives/list/users@ovirt.org/message/SLXLQ4BLQUPBV5355DFFACF6LFJX4MWY/
>   
___
Users mailing list -- users@ovirt.org
To unsubscribe send an email to users-le...@ovirt.org
Privacy Statement: https://www.ovirt.org/privacy-policy.html
oVirt Code of Conduct: 
https://www.ovirt.org/community/about/community-guidelines/
List Archives: 
https://lists.ovirt.org/archives/list/users@ovirt.org/message/XPUTVULWCBIRWJJZMHWRO7XB4VBVBSHU/


[ovirt-users] Re: Data recovery from (now unused, but still mounted) Gluster Volume for a single VM

2021-08-06 Thread David White via Users
Thank you for all the responses.
Following Strahil's instructions, I *think* that I was able to reconstruct the 
disk image. I'm just waiting for that image to finish downloading onto my local 
machine, at which point I'll try to import into VirtualBox or something. 
Fingers crossed!

Worst case scenario, I do have backups for that particular VM from 3 months 
ago, which I have already restored onto a new VM.
Losing 3 months of data is much better than losing 100% of the data from the 
past 2-3+ years.

Thank you.

> First of all you diddn't 'mkfs.xfs -i size=512' . You just 'mkfs.xfs' , whis 
> is not good and could have caused your VM problems. Also , check with 
> xfs_info the isize of the FS.

Ok, so right now, my production cluster is operating off of a single brick. I 
was planning on expanding the storage on the 2nd host next week, and adding 
that back into the cluster, and getting the Replica 2, Arbiter 1 redundancy 
working again.

How would you recommend I proceed with that plan, knowing that I'm currently 
operating off of a single brick in which I did NOT specify the size with 
`mkfs.xfs -i size=512?
Should I specify the size on the new brick I build next week, and then once 
everything is healed, reformat the current brick?

> And then there is a lot of information missing between the lines: I guess you 
> are using a 3 node HCI setup and were adding new disks (/dev/sdb) on all 
> three nodes and trying to move the glusterfs to those new bigger disks?

You are correct in that I'm using 3-node HCI. I originally built HCI with 
Gluster replication on all 3 nodes (Replica 3). As I'm increasing the storage, 
I'm also moving to an architecture of Replica 2/Arbiter 1. So yes, the plan was:

1) Convert FROM Replica 3 TO replica 2/arbiter 1
2) Convert again down to a Replica 1 (so no replication... just operating 
storage on a single host)
3) Rebuild the RAID array (with larger storage) on one of the unused hosts, and 
rebuild the gluster bricks
4) Add the larger RAID back into gluster, let it heal
5) Now, remove the bricks from the host with the smaller storage -- THIS is 
where things went awry, and what caused the data loss on this 1 particular VM
--- This is where I am currently ---
6) Rebuild the RAID array on the remaining host that is now unused (This is 
what I am / was planning to do next week)




Sent with ProtonMail Secure Email.

‐‐‐ Original Message ‐‐‐

On Thursday, August 5th, 2021 at 3:12 PM, Thomas Hoberg  
wrote:

> If you manage to export the disk image via the GUI, the result should be a 
> qcow2 format file, which you can mount/attach to anything Linux (well, if the 
> VM was Linux... it didn't say)
> 

> But it's perhaps easier to simply try to attach the disk of the failed VM as 
> a secondary to a live VM to recover the data.
> 

> Users mailing list -- users@ovirt.org
> 

> To unsubscribe send an email to users-le...@ovirt.org
> 

> Privacy Statement: https://www.ovirt.org/privacy-policy.html
> 

> oVirt Code of Conduct: 
> https://www.ovirt.org/community/about/community-guidelines/
> 

> List Archives: 
> https://lists.ovirt.org/archives/list/users@ovirt.org/message/SLXLQ4BLQUPBV5355DFFACF6LFJX4MWY/

publickey - dmwhite823@protonmail.com - 0x320CD582.asc
Description: application/pgp-keys


signature.asc
Description: OpenPGP digital signature
___
Users mailing list -- users@ovirt.org
To unsubscribe send an email to users-le...@ovirt.org
Privacy Statement: https://www.ovirt.org/privacy-policy.html
oVirt Code of Conduct: 
https://www.ovirt.org/community/about/community-guidelines/
List Archives: 
https://lists.ovirt.org/archives/list/users@ovirt.org/message/CZDHKGQES4ZOGGFJIBB46CZEGD647DLZ/


[ovirt-users] Re: Data recovery from (now unused, but still mounted) Gluster Volume for a single VM

2021-08-05 Thread Thomas Hoberg
If you manage to export the disk image via the GUI, the result should be a 
qcow2 format file, which you can mount/attach to anything Linux (well, if the 
VM was Linux... it didn't say)

But it's perhaps easier to simply try to attach the disk of the failed VM as a 
secondary to a live VM to recover the data.
___
Users mailing list -- users@ovirt.org
To unsubscribe send an email to users-le...@ovirt.org
Privacy Statement: https://www.ovirt.org/privacy-policy.html
oVirt Code of Conduct: 
https://www.ovirt.org/community/about/community-guidelines/
List Archives: 
https://lists.ovirt.org/archives/list/users@ovirt.org/message/SLXLQ4BLQUPBV5355DFFACF6LFJX4MWY/


[ovirt-users] Re: Data recovery from (now unused, but still mounted) Gluster Volume for a single VM

2021-08-05 Thread Thomas Hoberg
First off, I have very little hope, you'll be able to recover your data working 
at gluster level...

And then there is a lot of information missing between the lines: I guess you 
are using a 3 node HCI setup and were adding new disks (/dev/sdb) on all three 
nodes and trying to move the glusterfs to those new bigger disks?

Resizing/moving/adding or removing disks are "natural" operations for Gluster. 
But oVirt isn't "gluster native" and may not be so forgiving if you just swap 
device paths on bricks.


Practical guides on how to replace the storage without down time (after all 
this is a HA solution, right?) are somehow missing from the oVirt 
documentation, and if I was a rich man, perhaps I'd get myself an RHV support 
contract and see if RHEL engineers would say anything but "not supported".


The first thing I'd recommend is to create some temporary space. I found using 
an extra disk as NFS storage on one of the hosts was a good way to gain some 
maneuvering room e.g. for backups.

You can try to attach the disk of the broken VM as a secondary to another good 
VM to see if the data can be salvaged from there. But before you attach it (and 
perhaps an automatic fsck ruins it for you), you can perhaps create a copy to 
the NFS export/backup (domain).

If you weren't out of space, you'd just create a local copy and work with that. 
You can also try exporting the disk image, but there is a lot of untested or 
slow code in that operation from my experience.

If that image happens to be empty (I've seen that happen) or the data on it 
cannot be recovered, there is little to be gained, by trying to work at the 
GlusterFS level. The logical disk image file will be chunked into 64MB bits and 
their order is buried deep either in GlusterFS or in oVirt and perhaps your 
business is the better place to invest your energy.

But there is a good chance the data portion of that disk image still has your 
data. The fact that oVirt/KVM generally pauses VMs when it has issues with the 
storage, tends to preserve and protect your data rather better than what 
happens when physical hosts suffer brown outs or power glitches.

I guess you'll have learned that oVirt doesn't protect you from making 
mistakes, it only tries to offer some resilience against faults.

It's good and valuable to report these things, because it helps others to 
learn, too.

I sincerely hope you'll make do!
___
Users mailing list -- users@ovirt.org
To unsubscribe send an email to users-le...@ovirt.org
Privacy Statement: https://www.ovirt.org/privacy-policy.html
oVirt Code of Conduct: 
https://www.ovirt.org/community/about/community-guidelines/
List Archives: 
https://lists.ovirt.org/archives/list/users@ovirt.org/message/XSCXBSKCI3RKM5FUH57WG6JCMHOE7PMB/


[ovirt-users] Re: Data recovery from (now unused, but still mounted) Gluster Volume for a single VM

2021-08-04 Thread Strahil Nikolov via Users
*should be 2
 
 
  On Thu, Aug 5, 2021 at 7:42, Strahil Nikolov wrote:   
when you use 'remove-brick replica 1', you need to specify the removed bricks 
which should be 1 (data brick and arbiter).Something is mising in your 
description.
Best Regards,Strahil Nikolov
 
 
  On Thu, Aug 5, 2021 at 7:33, Strahil Nikolov via Users 
wrote:   ___
Users mailing list -- users@ovirt.org
To unsubscribe send an email to users-le...@ovirt.org
Privacy Statement: https://www.ovirt.org/privacy-policy.html
oVirt Code of Conduct: 
https://www.ovirt.org/community/about/community-guidelines/
List Archives: 
https://lists.ovirt.org/archives/list/users@ovirt.org/message/K6DFRDDV5HTRZFLXKO5274AB4RUXOHV6/
  
  
___
Users mailing list -- users@ovirt.org
To unsubscribe send an email to users-le...@ovirt.org
Privacy Statement: https://www.ovirt.org/privacy-policy.html
oVirt Code of Conduct: 
https://www.ovirt.org/community/about/community-guidelines/
List Archives: 
https://lists.ovirt.org/archives/list/users@ovirt.org/message/GQHJPBVCOT3N6AD2TJMF2RT4PANR2KPK/


[ovirt-users] Re: Data recovery from (now unused, but still mounted) Gluster Volume for a single VM

2021-08-04 Thread Strahil Nikolov via Users
when you use 'remove-brick replica 1', you need to specify the removed bricks 
which should be 1 (data brick and arbiter).Something is mising in your 
description.
Best Regards,Strahil Nikolov
 
 
  On Thu, Aug 5, 2021 at 7:33, Strahil Nikolov via Users 
wrote:   ___
Users mailing list -- users@ovirt.org
To unsubscribe send an email to users-le...@ovirt.org
Privacy Statement: https://www.ovirt.org/privacy-policy.html
oVirt Code of Conduct: 
https://www.ovirt.org/community/about/community-guidelines/
List Archives: 
https://lists.ovirt.org/archives/list/users@ovirt.org/message/K6DFRDDV5HTRZFLXKO5274AB4RUXOHV6/
  
___
Users mailing list -- users@ovirt.org
To unsubscribe send an email to users-le...@ovirt.org
Privacy Statement: https://www.ovirt.org/privacy-policy.html
oVirt Code of Conduct: 
https://www.ovirt.org/community/about/community-guidelines/
List Archives: 
https://lists.ovirt.org/archives/list/users@ovirt.org/message/26R3AM3EEAEQ5LTORWFX7RMY4F5YYI65/


[ovirt-users] Re: Data recovery from (now unused, but still mounted) Gluster Volume for a single VM

2021-08-04 Thread Strahil Nikolov via Users
First of all you diddn't 'mkfs.xfs -i size=512' . You just 'mkfs.xfs' , whis is 
not good and could have caused your VM problems. Also , check with xfs_info the 
isize of the FS.
You have to find the uuid of the disks of the affected VM.Then go to the 
removed host,and find that file -> this is the so called shard1.Then you need 
to find the gfid of the file.The easiest way is to go to the "dead" cluster and 
find the hard links in the .gluster directory.
Something like this:
ssh old host (the one specified in the remove-brick)cd 
/gluster_bricks/data/data//images/ls -li  
-> take the first numberfind /gluster_bricks/data/data -inum 
It should show you both the file and the gfid.
Then copy the file from images//file.Go to 
/gluster_bricks/data/data/.shardList all files of:
ls -l .*
These are your shards. Just cat first file + shards (in the number order) into 
another file.

This should be your VM disk.

Best Regards,Strahil Nikolov
 
 
  On Tue, Aug 3, 2021 at 12:58, David White via Users wrote:   
Hi Patrick,
This would be amazing, if possible.

Checking /gluster_bricks/data/data on the host where I've removed (but not 
replaced) the bricks, I see a single directory.
When I go into that directory, I see two directories:

dom_md
images

If I go into the images directory, I think I see the hash folders that you're 
referring to, and inside each of those, I see the 3 files you referenced.

Unfortunately, those files clearly don't have all of the data.
The parent folder for all of the hash folders is only 687M.

[root@cha1-storage data]# du -skh *
687M    31366488-d845-445b-b371-e059bf71f34f

And the "iso" files are small. The one I'm looking at now is only 19M.
It appears that most of the actual data is located in 
/gluster_bricks/data/data/.glusterfs, and all of those folders are totally 
random, incomprehensible directories that I'm not sure how to understand.

Perhaps you were on an older version of Gluster, and the actual data hierarchy 
is different?
I don't know. But I do see the 3 files you referenced, so that's a start, even 
if they are nowhere near the correct size.

Sent with ProtonMail Secure Email.

‐‐‐ Original Message ‐‐‐

On Tuesday, August 3rd, 2021 at 1:49 AM, Patrick Lomakin 
 wrote:

> Greetings, I once wondered how data is stored between replicated bricks. 
> Specifically, how disks are stored on the storage domain in Gluster. I 
> checked a mounted brick via the standard path (path may be different) 
> /gluster/data/data and saw many directories there. Maybe the hierarchy is 
> different, can't check now. But in the end I got a list of directories. Each 
> directory name is a disk image hash. After going to a directory such as /HASH 
> there were 3 files. The first is a disk in raw/iso/qcow2 format (but the file 
> has no extension, I looked at the size) the other two files are the 
> configuration and metadata. I downloaded the disk image file (.iso) to my 
> computer via the curl command and service www.station307.com (no ads). And I 
> got the original .iso which uploaded to the storage domain through the hosted 
> engine interface. Maybe this way you can download the disk image to your 
> computer and then load it via the GUI and connect it to a virtual machine. 
> Good luck!
> 

> Users mailing list -- users@ovirt.org
> 

> To unsubscribe send an email to users-le...@ovirt.org
> 

> Privacy Statement: https://www.ovirt.org/privacy-policy.html
> 

> oVirt Code of Conduct: 
> https://www.ovirt.org/community/about/community-guidelines/
> 

> List Archives: 
> https://lists.ovirt.org/archives/list/users@ovirt.org/message/A6XITCEX5RNQB37YKDCR4EUKTV6W4HIR/
>   
___
Users mailing list -- users@ovirt.org
To unsubscribe send an email to users-le...@ovirt.org
Privacy Statement: https://www.ovirt.org/privacy-policy.html
oVirt Code of Conduct: 
https://www.ovirt.org/community/about/community-guidelines/
List Archives: 
https://lists.ovirt.org/archives/list/users@ovirt.org/message/K6DFRDDV5HTRZFLXKO5274AB4RUXOHV6/


[ovirt-users] Re: Data recovery from (now unused, but still mounted) Gluster Volume for a single VM

2021-08-03 Thread David White via Users
Hi Patrick,
This would be amazing, if possible.

Checking /gluster_bricks/data/data on the host where I've removed (but not 
replaced) the bricks, I see a single directory.
When I go into that directory, I see two directories:

dom_md
images

If I go into the images directory, I think I see the hash folders that you're 
referring to, and inside each of those, I see the 3 files you referenced.

Unfortunately, those files clearly don't have all of the data.
The parent folder for all of the hash folders is only 687M.

[root@cha1-storage data]# du -skh *
687M31366488-d845-445b-b371-e059bf71f34f

And the "iso" files are small. The one I'm looking at now is only 19M.
It appears that most of the actual data is located in 
/gluster_bricks/data/data/.glusterfs, and all of those folders are totally 
random, incomprehensible directories that I'm not sure how to understand.

Perhaps you were on an older version of Gluster, and the actual data hierarchy 
is different?
I don't know. But I do see the 3 files you referenced, so that's a start, even 
if they are nowhere near the correct size.

Sent with ProtonMail Secure Email.

‐‐‐ Original Message ‐‐‐

On Tuesday, August 3rd, 2021 at 1:49 AM, Patrick Lomakin 
 wrote:

> Greetings, I once wondered how data is stored between replicated bricks. 
> Specifically, how disks are stored on the storage domain in Gluster. I 
> checked a mounted brick via the standard path (path may be different) 
> /gluster/data/data and saw many directories there. Maybe the hierarchy is 
> different, can't check now. But in the end I got a list of directories. Each 
> directory name is a disk image hash. After going to a directory such as /HASH 
> there were 3 files. The first is a disk in raw/iso/qcow2 format (but the file 
> has no extension, I looked at the size) the other two files are the 
> configuration and metadata. I downloaded the disk image file (.iso) to my 
> computer via the curl command and service www.station307.com (no ads). And I 
> got the original .iso which uploaded to the storage domain through the hosted 
> engine interface. Maybe this way you can download the disk image to your 
> computer and then load it via the GUI and connect it to a virtual machine. 
> Good luck!
> 

> Users mailing list -- users@ovirt.org
> 

> To unsubscribe send an email to users-le...@ovirt.org
> 

> Privacy Statement: https://www.ovirt.org/privacy-policy.html
> 

> oVirt Code of Conduct: 
> https://www.ovirt.org/community/about/community-guidelines/
> 

> List Archives: 
> https://lists.ovirt.org/archives/list/users@ovirt.org/message/A6XITCEX5RNQB37YKDCR4EUKTV6W4HIR/

publickey - dmwhite823@protonmail.com - 0x320CD582.asc
Description: application/pgp-keys


signature.asc
Description: OpenPGP digital signature
___
Users mailing list -- users@ovirt.org
To unsubscribe send an email to users-le...@ovirt.org
Privacy Statement: https://www.ovirt.org/privacy-policy.html
oVirt Code of Conduct: 
https://www.ovirt.org/community/about/community-guidelines/
List Archives: 
https://lists.ovirt.org/archives/list/users@ovirt.org/message/QFCDE36MUQFFNQQULUYWWI7DBU3GG2KF/


[ovirt-users] Re: Data recovery from (now unused, but still mounted) Gluster Volume for a single VM

2021-08-02 Thread Patrick Lomakin
Greetings, I once wondered how data is stored between replicated bricks. 
Specifically, how disks are stored on the storage domain in Gluster. I checked 
a mounted brick via the standard path (path may be different) 
/gluster/data/data and saw many directories there. Maybe the hierarchy is 
different, can't check now. But in the end I got a list of directories. Each 
directory name is a disk image hash. After going to a directory such as 
/**HASH** there were 3 files. The first is a disk in raw/iso/qcow2 format (but 
the file has no extension, I looked at the size) the other two files are the 
configuration and metadata. I downloaded the disk image file (.iso) to my 
computer via the curl command and service www.station307.com (no ads). And I 
got the original .iso which uploaded to the storage domain through the hosted 
engine interface. Maybe this way you can download the disk image to your 
computer and then load it via the GUI and connect it to a virtual machine. Good 
luck!
___
Users mailing list -- users@ovirt.org
To unsubscribe send an email to users-le...@ovirt.org
Privacy Statement: https://www.ovirt.org/privacy-policy.html
oVirt Code of Conduct: 
https://www.ovirt.org/community/about/community-guidelines/
List Archives: 
https://lists.ovirt.org/archives/list/users@ovirt.org/message/A6XITCEX5RNQB37YKDCR4EUKTV6W4HIR/