Monday, June 08, 2015

Managing Docker images with tags

When you build Docker images many times, you will find it is very necessary to manage images with tags.
If you build an image without a tag, the default tag 'latest' is created automatically.
docker build -t company/myimage .
The complete name is company/myimage:latest

When you need to update a new version of company/myimage, you don't need to create an image company/myimage_v2. You should create an image with the same name and a new tag.
docker build -t company/myimage:v2 .
And set it latest
docker tag -f company/myimage:v2 company/myimage:latest

So your new image has two tags: v2 and latest. When you start a container based on company/myimage, company/myimage:latest will be used.