Save Data protection keys even after container is destroyed

[MichaelSimons]

Copied from dotnet/dotnet-docker#295 by @VenkateshSrini

Steps to reproduce the issue

1. Run an aps.net core app using the command
   docker run -p 5000:80 --name containerda containerda-img

Expected behavior

Should run with out any warning.

Actual behavior

I get an warning saying

warn: Microsoft.AspNetCore.DataProtection.Repositories.FileSystemXmlRepository[60]
Storing keys in a directory '/root/.aspnet/DataProtection-Keys' that may not be persisted outside of the container
. Protected data will be unavailable when container is destroyed.

Additional information (e.g. issue happens only occasionally)

Output of docker version

Docker version 17.06.2-ce, build cec0b72

I need a method to persist these keys even when the container is destroyed

Copied from dotnet/dotnet-docker#295 (comment) by @natemcmaster
Seems like a good candidate for aspnetcore documentation. https://github.com/aspnet/docs There are some docs already, but none for docker-specific scenarios.

Basically, you'll need to store the keys in a folder that is docker volume (i.e. shared volme or a host mounted volume), or you'll need to store them in an external provider, like Azure Key Vault or Redis.

cref aspnet/DataProtection#185

_Copied from dotnet/dotnet-docker#295 (comment) by @VenkateshSrini
@natemcmaster,
I have tried to mount a volume like this
docker run -v d:/venkatesh/aspnetcore/2.0/containerdasample/publish/containerapp/keys:/root/.aspnet/dataprotection-keys -p 5000:80 --name containerda containerda-img
In this I would expect the key to be stored in mounted volume but even after that I keep getting this error. I do not want to loose the encryption key. Can you please share me some link that has sample solution to this problem

[natemcmaster]

@VenkateshSrini I recommend this article on configuring data protection key storage in Docker. It includes samples on how to persist keys to a different location or an external key repo.

https://docs.microsoft.com/en-us/aspnet/core/security/data-protection/configuration/overview

Closing for now as there isn't anything actionable yet. We can reopen if you are still having issues.