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In SQL Server 2019 specifically, I can't backup to network shares and receive event ID 3041, 3624, and 17066. Per those messages, I've ran DBCC CHECKDB and all databases are fine. I can backup to the local drive without issue. I am running the SQL Server Agent with all the defaults and it logs on as "NT SERVICE\SQLSERVERAGENT". On the remote share, share permissions are everyone=full control, and I have verified that the computer account in question has full control of the share. I know that it can read and write to the directories as I see it logging on successfully in the event viewer and if the backup folders don't exist, it creates the folder structure and the owner is the computer account in question. I've worked with multiple versions of SQL and backed up to network shares before, so I'm fairly certain I have configured everything correctly and so I'm starting to lean towards this is a bug.
A system assertion check has failed. Check the SQL Server error log for details. Typically, an assertion failure is caused by a software bug or data corruption. To check for database corruption, consider running DBCC CHECKDB. If you agreed to send dumps to Microsoft during setup, a mini dump will be sent to Microsoft. An update might be available from Microsoft in the latest Service Pack or in a Hotfix from Technical Support.
SQL Server Assertion: File: <mediaWrite.cpp>, line=603 Failed Assertion = '(m_pWriteBuffer->GetCurrentSize ()% GetBlockSize ()) == 0'. This error may be timing-related. If the error persists after rerunning the statement, use DBCC CHECKDB to check the database for structural integrity, or restart the server to ensure in-memory data structures are not corrupted.
I also failed to mention the network share is on a Windows Server 2019 machine.
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What is the size of DB? If it is too big can you try with smaller size DB?
The largest db is under 6GB, but it doesn't work for any of the system databases either, the smallest being 6MB, even I run the backup command direct from an SQL query, I get the same error.
An assertion error indicates a bug in the product. They have a check for a condition which is supposed to true at that point and if it is not, they realise that they have lost ocntrol.
First check that you are on CU7, the latested cumulative update of SQL Server. If you get the error with CU7, open a case with Microsoft.
(It could be that the operation you are trying should fail. But it should not fail with that error message. That's a bug.)
I just updated from CU6 to CU7 and the issue persists. So, I've never opened up a ticket with MS before over SQL, do they not allow tech support on their products without a valid support contract anymore? For purchasing the software, you don't even get a year of support or anything without purchasing software assurance or something? The only thing I see is that it says to post to all these various forums, which I've done, and a pay per incident option of $499, which is aggravating to put it nicely. I don't understand why I should have to pay to report a broken product. Hopefully I'm just missing something.
Yes, there is quite a stiff price tag for opening a case. However, if the issue is deemed to be related to a deficiency in the product, you will be reimbursed.
And as I said, in my opinion the above is a bug. But it may only be in the sense that you should get a better error message. Since this happens with network shares, there is most likely an environment-dependent component here as well, like a driver which is not behaving as expected.
And while $499 is not a small amount of money, you will also have to ask yourself how much it will cost your organisation to find the issue in the network topology fumbling around in the dark. (As you are with this error message.)
Hi @Erland Sommarskog ,
Yes, the issue is still happening in my SQL Server below:
Microsoft SQL Server 2019 (RTM-CU18-GDR) (KB5021124) - 15.0.4280.7 (X64) Jan 23 2023 12:37:13 Copyright (C) 2019 Microsoft Corporation Developer Edition (64-bit) on Windows Server 2022 Datacenter Azure Edition 10.0 <X64> (Build 20348: ) (Hypervisor)
is there any updated hotfix for this type of issue?
I can only recommend:
Since the checkdb went fine and also you are able to backup on local storage attached I would say that the network storage has some problem look at the 2nd error message.
SQL Server Assertion: File: <mediaWrite.cpp>, line=603 Failed Assertion = '(m_pWriteBuffer->GetCurrentSize ()% GetBlockSize ()) == 0'. This error may be timing-related. If the error persists after rerunning the statement, use DBCC CHECKDB to check the database for structural integrity, or restart the server to ensure in-memory data structures are not corrupted.
This shows that SQL Server is not able to write data to particular block. I would suggest you to gt in touch with storage team to check about this network shared storage.
Just posting an update, it is still happening as of CU8. I have also even tried changing the SQL Server Agent service account to a domain administrator with backup operator privileges, and still the same error.
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Agent is irrelevant. The one writing to that share is the database engine service. Try changing that and see if there is a difference.