Azure docker: linuxFxVersion vs DOCKER_CUSTOM_IMAGE_NAME

Question

I have these three release steps in Azure De Ops:

AzureRmWebAppDeployment@4 - which deploys a docker image to my staging site
AzureResourceGroupDeployment@2 which deploys all the appsettings and properties with an ARM template
AzureAppServiceManage@0 - it swaps staging into production

Step 1 is applied so I am sure that the docker image is pulled to the staging slot (without it and only applying the ARM the swap begins before the pull is over, and I dont like that). Step 2 is to be sure that all environment variables and properties. Step 1 adds the DOCKER_CUSTOM_IMAGE_NAME environment variable and by that triggers a docker pull, but in step 3 I manually set the linuxFxVersion property. Both points to the same image tag. I don't set the DOCKER_CUSTOM_IMAGE_NAME in my ARM template, so when I deploy my ARM, only linuxFxVersion is set. But in essence it pulls nothing, because step 2 has already pulled the image.

Is there anything wrong in removing the DOCKER_CUSTOM_IMAGE_NAME? Or? What is the difference between linuFxVersion and DOCKER_CUSTOM_IMAGE_NAME? Do I need both, or is one of them good enough?

To use a custom image from a public Docker Hub registry, the application need to have this specific application setting DOCKER_CUSTOM_IMAGE_NAME — user12163310
– user12163310, Commented Feb 25, 2020 at 15:23
@blank but the AzureRmWebAppDeployment@4 sets both linuxFxVersion and DOCKER_CUSTOM_IMAGE_NAME. But I can easily leave one of them out and still get my docker pulled. What are the difference? — mslot
– mslot, Commented Feb 25, 2020 at 16:14

sa23 · Accepted Answer · 2020-06-20 07:46:53Z

7

LinuxFxVersion and DOCKER_CUSTOM_IMAGE_NAME are both ways to specify the image to be used in a Linux function app or a Linux web app.

LinuxFxVersion is given higher precedence. If that value is invalid or empty,it would use DOCKER_CUSTOM_IMAGE_NAME. LinuxFxVersion is recommended since it can be used to set both custom container images as well as blessed images.

answered Jun 20, 2020 at 7:46

sa23

3482 silver badges5 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

zolty13 Over a year ago

where do you find this inforamtion?

Daniil Samoylov Over a year ago

@zolty13 Just found it in Azure Docs learn.microsoft.com/en-us/azure/app-service/… inside the tip block under Deploy the image and test the app

Collectives™ on Stack Overflow

Azure docker: linuxFxVersion vs DOCKER_CUSTOM_IMAGE_NAME

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related