when this lines are given in a file:

```
docker://docker.io/some-repo/my-image:v1.1.2 docker://docker.io/some-repo/my-image:v1.1.2
docker://ghcr.io/some-repo/my-image:v1.1.2 docker://ghcr.io/some-repo/my-image:v1.1.2
docker://ecr.aws/some-repo/my-image:v1.1.2 docker://ecr.aws/some-repo/my-image:v1.1.2

```

if i execute

```bash
awk -F: -v var2="example.local/" 'BEGIN{FS=OFS=" "} {gsub(/(\/\/.*\.[a-z{2,6}]*\/)/, var2, $2)} 1'

```

results in

```
docker://docker.io/some-repo/my-image:v1.1.2 docker:example.local/some-repo/my-image:v1.1.2
docker://ghcr.io/some-repo/my-image:v1.1.2 docker:example.local/some-repo/my-image:v1.1.2
docker://ecr.aws/some-repo/my-image:v1.1.2 docker:example.local/some-repo/my-image:v1.1.2

```

How can i only replace the domain part in the 2nd column? In this case "docker.io|ghcr.io|ecr.aws" in a generic way.