Fixes location of mssql volume to only empty data

[potiuk]

Seems that running mssql on self-hosted runner makes mssql
container fail with empty volume. This PR is to check if
just providing the empty 'data' and not removing logs folder
causes the failure.

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[potiuk]

cc: @aneesh-joseph

[github-actions]

The PR most likely needs to run full matrix of tests because it modifies parts of the core of Airflow. However, committers might decide to merge it quickly and take the risk. If they don't merge it quickly - please rebase it to the latest master at your convenience, or amend the last commit of the PR, and push it with --force-with-lease.

[potiuk]

Did not help it seems . I will remove the volume completely and see how it works.

[potiuk]

Not helping. Time to try to reproduce it in the runner itself:

Same error (from the artifacts):

SQL Server 2019 will run as non-root by default.
This container is running as user mssql.
To learn more visit https://go.microsoft.com/fwlink/?linkid=2099216.
2021-05-28 18:29:45.17 Server      Setup step is copying system data file 'C:\templatedata\master.mdf' to '/var/opt/mssql/data/master.mdf'.

2021-05-28 18:29:45.28 Server      Did not find an existing master data file /var/opt/mssql/data/master.mdf, copying the missing default master and other system database files. If you have moved the database location, but not moved the database files, startup may fail. To repair: shutdown SQL Server, move the master database to configured location, and restart.

2021-05-28 18:29:45.29 Server      Setup step is copying system data file 'C:\templatedata\mastlog.ldf' to '/var/opt/mssql/data/mastlog.ldf'.

2021-05-28 18:29:45.29 Server      Setup step is copying system data file 'C:\templatedata\model.mdf' to '/var/opt/mssql/data/model.mdf'.

2021-05-28 18:29:45.31 Server      Setup step is copying system data file 'C:\templatedata\modellog.ldf' to '/var/opt/mssql/data/modellog.ldf'.

2021-05-28 18:29:45.32 Server      Setup step is copying system data file 'C:\templatedata\msdbdata.mdf' to '/var/opt/mssql/data/msdbdata.mdf'.

2021-05-28 18:29:45.34 Server      Setup step is copying system data file 'C:\templatedata\msdblog.ldf' to '/var/opt/mssql/data/msdblog.ldf'.

2021-05-28 18:29:45.35 Server      Setup step is FORCE copying system data file 'C:\templatedata\model_replicatedmaster.mdf' to '/var/opt/mssql/data/model_replicatedmaster.mdf'.

2021-05-28 18:29:45.36 Server      Setup step is FORCE copying system data file 'C:\templatedata\model_replicatedmaster.ldf' to '/var/opt/mssql/data/model_replicatedmaster.ldf'.

2021-05-28 18:29:45.37 Server      Setup step is FORCE copying system data file 'C:\templatedata\model_msdbdata.mdf' to '/var/opt/mssql/data/model_msdbdata.mdf'.

2021-05-28 18:29:45.39 Server      Setup step is FORCE copying system data file 'C:\templatedata\model_msdblog.ldf' to '/var/opt/mssql/data/model_msdblog.ldf'.

2021-05-28 18:29:45.48 Server      Microsoft SQL Server 2019 (RTM-CU10) (KB5001090) - 15.0.4123.1 (X64) 

	Mar 22 2021 18:10:24 

	Copyright (C) 2019 Microsoft Corporation

	Developer Edition (64-bit) on Linux (Ubuntu 20.04.2 LTS) <X64>

2021-05-28 18:29:45.49 Server      UTC adjustment: 0:00

2021-05-28 18:29:45.49 Server      (c) Microsoft Corporation.

2021-05-28 18:29:45.49 Server      All rights reserved.

2021-05-28 18:29:45.50 Server      Server process ID is 388.

2021-05-28 18:29:45.50 Server      Logging SQL Server messages in file '/var/opt/mssql/log/errorlog'.

2021-05-28 18:29:45.50 Server      Registry startup parameters: 

	 -d /var/opt/mssql/data/master.mdf

	 -l /var/opt/mssql/data/mastlog.ldf

	 -e /var/opt/mssql/log/errorlog

2021-05-28 18:29:45.51 Server      Error: 17113, Severity: 16, State: 1.

2021-05-28 18:29:45.51 Server      Error 87(The parameter is incorrect.) occurred while opening file '/var/opt/mssql/data/master.mdf' to obtain configuration information at startup. An invalid startup option might have caused the error. Verify your startup options, and correct or remove them if necessary.

SQL Server 2019 will run as non-root by default.
This container is running as user mssql.
Your master database file is owned by mssql.
To learn more visit https://go.microsoft.com/fwlink/?linkid=2099216.

[potiuk]

Ok. I think I found the reason. Seems that our docker engine is using ZFS as backing storage and MsSQL does not work with it:

microsoft/mssql-docker#13

The solution will be to change backing storage for our docker engine. It also might be (although this is less likely) that it is caused by the fact that we are using tmpfs under the hood (but I think this should have no impact whatsoever as this is one layer "deeper" in the file-system approach and docker uses a backing storage filesystem on top of the underlying tmpfs.

[potiuk]

oh NO. It is the problem with tmpfs :(

This is still an issue on other file systems that do not support O_DIRECT like ramfs.

[potiuk]

What we can do is to have two docker engine installation and for MsSQL we could choose the file-backed one. It will be slower, but it will work.

[potiuk]

closing this PR then to solve it differently.

[ashb]

What we can do is to have two docker engine installation and for MsSQL we could choose the file-backed one. It will be slower, but it will work.

Could we volume mount a different path that isn't on tmpfs? (That seems less work then a second docker daemon)

[potiuk]

Could we volume mount a different path that isn't on tmpfs? (That seems less work then a second docker daemon)

Might be better option indeed. Worth checking.