如何在 SQL 服务器容器中更改数据库备份的文件所有权

Question

I'm following this guide to restore a database backup https://docs.microsoft.com/en-us/sql/linux/tutorial-restore-backup-in-sql-server-container?view=sql-server-ver15

I used docker cp command to copy the DB backup files to the container docker exec -it SQLContainer mkdir /var/opt/mssql/backup

docker cp MyDb.bak SQLContainer:/var/opt/mssql/backup/

However when trying to restore the DB by running the following query in SSMS, an error message is shown

RESTORE DATABASE MyDB FROM DISK='/var/opt/mssql/backup/MyDB.bak'

Operating system error 5(Access is denied.).

I tried copying using docker cp -a, which sets file ownership to same as destination, but I got this error.

docker cp -a MyDb.bak SQLContainer:/var/opt/mssql/backup/

Error response from daemon: getent unable to find entry "mssql" in passwd database

I'm using Microsoft's image and I don't know the password for root user, the container runs using mssql user, so chown doesn't work either. How can I change the file permissions so DB restore works?

Answer 1

Turns out when I copied the database backup files from the Windows host to the Ubuntu machine, the files were owned by root user and all other users didn't have read permission. Adding read permission to the file before copying to the docker container works and the server was able to read the files.

sudo chmod a+r MyDb.bak

sudo docker cp MyDb.bak SQLContainer:/var/opt/mssql/backup/

Answer 2

I had a similar issue just today, about the same time as this incident, just attaching MDF and LDF files.

By doing the chmod go+w before copying files without the -a I was able to get SQL Server to treat them as writeable. Prior to that I was getting error messages whenever any update was performed.