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khimicho
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Mounter is not responding, please check if backup repository is online and try again. Case #04758073

Post by khimicho »

Case #04758073
Hello everyone! I have a problem restoring data from the backup. Recovery begins, but after 15-20% - an error occurs - Mounter is not responding, please check if backup repository is online and try again. Tried several times from different backups, but the error is similar. I decided that this was a network problem, so I tried to move the files to another repository and then even to the local PC drive where Veeam B&R is installed. This did not lead to a positive result. Please clarify, maybe someone has encountered this error? Could this be due to the size of the file being recovered? 80 GB (other, smaller files are restored successfully). (Stocks of free space are available on Veeam B&R server disks).

nikolaj
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Re: Mounter is not responding, please check if backup repository is online and try again. Case #04758073

Post by nikolaj »

Welcome to the forum, khimicho!

It's quite challenging to evaluate the situation without the logs (which is done by our support).

Since you've eliminated the possibility of potential network issues, I'd suggest checking the integrity of the backup file with Veeam Backup Validator .

The following article might help with that utility:
https://www.veeam.com/kb2086

khimicho
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Re: Mounter is not responding, please check if backup repository is online and try again. Case #04758073

Post by khimicho »

Launched the utility to my backup.

At the end I will write whether this led to a positive result.

khimicho
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Re: Mounter is not responding, please check if backup repository is online and try again. Case #04758073

Post by khimicho »

Skipping VM 'TH': File "TH_NEW.vhdx" is corrupted. Failed to decompress LZ4 block: Incorrect decompression result or length (result: '261599', expected length: '262144').


Statistic:
VM count: 1
Incomplete VM count: 0
Failed VM count: 1
Files count: 4
Total size: 850,0 GB

Validation failed.

The following VMs are corrupted:
1. 'TH': File "TH_NEW.vhdx" is corrupted. Failed to decompress LZ4 block: Incorrect decompression result or length (result: '261599', expected length: '262144').


I received the answer: The backup is damaged.

What could have caused the damage and how to avoid such situations?

nikolaj
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Re: Mounter is not responding, please check if backup repository is online and try again. Case #04758073

Post by nikolaj »

I would recommend reviewing this article:
https://www.veeam.com/kb1795
Typically this error indicates hardware malfunction during storage or transmission of the backup file. Most types of storage are subject to a small degree of unrecoverable failure – this is commonly called Bit Rot.

Perhaps you should look into SMART health reports for your drives since they are the most common source of problems of such nature.

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Re: Mounter is not responding, please check if backup repository is online and try again. Case #04758073

Post by PetrM »

By the way, I'd also recommend to run SureBackup jobs periodically in order to check recoverability of backups.

Thanks!

khimicho
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Re: Mounter is not responding, please check if backup repository is online and try again. Case #04758073

Post by khimicho »

I checked all 4 discs. No broken sectors were identified. There are also no other errors, such as sector redirection or interface clock errors

Screenshots of the test posted on dropmefiles - https://dropmefiles.com/elScd

nikolaj
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Re: Mounter is not responding, please check if backup repository is online and try again. Case #04758073

Post by nikolaj »

Unfortunately, this is the extent of the expertise we can provide without diving into your environment.
I suggest sharing all these new found details in your support case.

As for this particular recovery, I think you should consider one of the options outlined in the Solution section of the aforementioned article:
If you are attempting restore and have multiple copies of the backup file, try using a different copy.
If you have other restore points, try an older full backup or an incremental associated with an older full.
If you are unable to recover the complete VM, file level recovery may still be possible.

khimicho
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Re: Mounter is not responding, please check if backup repository is online and try again. Case #04758073

Post by khimicho »

While checking the backups I noticed one feature.

Backups are not damaged only by those virtual machines that are installed in the same data center as the veeam repository.


If the hypervisors are in a different (in my case three) data center than the veeam repository - all copies are damaged.

What can lead to such a situation?

(In copy settings, data transfer is established via WAN)

Communication with all hypervisors is stable, the backup report is completed.


Maybe the date center is blocking certain ports?

Need to write a letter asking to open? What ports are used for backup from the hypervisor to the repository?

nikolaj
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Re: Mounter is not responding, please check if backup repository is online and try again. Case #04758073

Post by nikolaj »

If the hypervisors are in a different (in my case three) data center than the veeam repository - all copies are damaged.
So you're inferring that the backups become corrupted in the process of copying them to a target repo?
Do your backup copy jobs ever fail with any errors that could point out to a potential issue?
For instance:

Code: Select all

Error: Source WAN accelerator error:
I'd consider setting up Health check to perform periodic checks on the whole backup chain.
And of course it's crucial to get to the root cause of this problem with our support.

khimicho
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Re: Mounter is not responding, please check if backup repository is online and try again. Case #04758073

Post by khimicho » 1 person likes this post

A few days ago I set up a backup health check in job.

Yesterday I rechecked the copy using Veeam Backup Validator. Showed that the copy is healthy.

I will restore the data from this copy.

I will also set up a health check for other tasks.

Then I will check everything and write the result.

I hope my problem will be solved.

nikolaj
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Re: Mounter is not responding, please check if backup repository is online and try again. Case #04758073

Post by nikolaj »

Sounds like a plan, don't forget about SureBackup jobs!

khimicho
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Re: Mounter is not responding, please check if backup repository is online and try again. Case #04758073

Post by khimicho »

Please clarify.

Health check in terms of a copy - only checks the health of the backup?

Does it check and in case of a problem - corrects?

nikolaj
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Re: Mounter is not responding, please check if backup repository is online and try again. Case #04758073

Post by nikolaj »

Depending on the backup mode, the Health Check utility can rectify backup chains, however, the success of that remediation may vary.

More on how the tool works on particular types of backup chains can be found in this article of the user guide.

khimicho
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Re: Mounter is not responding, please check if backup repository is online and try again. Case #04758073

Post by khimicho »

Hi there.

Virtual machines are backed up after setting up a health check - they have become healthy and successfully pass the Veeam Validator test.

But copies made through Veeam Agent`s - still have problems of this kind -File "01E9966E" is corrupted. Failed to decompress LZ4 block:

What could be the reason? Is the backup algorithm of virtual machines different from physical ones?

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Re: Mounter is not responding, please check if backup repository is online and try again. Case #04758073

Post by foggy »

Health check itself doesn't prevent hardware issues, it just allows to detect it and re-copy the valid blocks from the source to obtain a valid and consistent restore point. So it is not the health check that 'fixed' the job, but rather the hardware issue just didn't show up for the backups created recently. And this is not the case for backups created by Agent.

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