We’re running a private docker registry (currently 0.8.1), to which we push our images. It is running with standalone set to default (true), and with no index specified. Now, we’re looking to set up private mirrors of that private registry. I configure the MIRROR_SOURCE with the IP_ADDR:PORT and MIRROR_TAGS_CACHE_TTL with a TTL, and pass both with -e on the container command line.
So far so good. I can push to this registry mirror, and pull anything that I have pushed there. I cannot, however, get it to act like a proper mirror, where on a cache miss it fetches from the upstream registry specified in MIRROR_SOURCE. Instead, I get an HTTP 500.
Is a docker index (such as ekristen/docker-index) required when enabling mirroring? Firewall config looks good. Pointers on what else I should be looking at would be appreciated.