Small. Simple. Secure.
On 2024-10-25 18:55 UTC we were notified via IRC that package repositories were missing for the edge branch. Investigation confirmed that, except for riscv64, repositories for all other architectures were missing. The repositories for all stable releases were still present.
Checking the dl-master mirror, the repositories there were missing as well. The next step was to check whether the builders themselves still contained all the packages, which fortunately was the case.
Each architecture and each release has a dedicated builder. A builder keeps a complete repository of all the packages it built. After it completes building a repository, it synchronizes the local repository with dl-master.alpinelinux.org, a single server which is tier 0 in our mirror infrastructure.
Next we have 3 tier 1 servers that are geographically spread, which synchronize with dl-master. These tier 1 servers also act as a backend for dl-cdn.alpinelinux.org and rsync.alpinelinux.org, which all other mirrors use to synchronize our repositories with.
