MirrorManager Infrastructure SOP

MirrorManager handles our mirroring system. It keeps track of lists of valid mirrors and handles handing out metalink URLs to end users to download packages from.

The backend server (mm-backend01) scans the master mirror (NFS mounted at /srv) using the mm2_update-master-directory-list script (umdl) for changes. Changed directories are detected by comparing the ctime to the value in the database.

The two crawlers (mm-crawler01 and mm-crawler02) compare the content on the mirrors with the results from umdl using RSYNC, HTTP, HTTPS. The crawler process on mm-crawler01 starts at 0:00 and 12:00 and at 2:00 and 14:00 on mm-crawler02.

If the content on the mirrors is the same as on the master those mirrors are included in the dynamic metalink/mirrorlist.

Every hour the backend server generates a python pickle which contains the information about the state of each mirror. This pickle file is used by the mirrorlist containers on the proxy servers to dynamically generate the metalink/mirrorlist for each client individually.

The frontend servers (mm-frontend01 and mm-frontend02) offer an interface to manipulate the mirrors. Each mirror-admin can only change the details of the associated mirror. Members of the FAS group sysadmin-web can seen and change all existing mirrors.

The mirrorlist provided by the frontend servers has no actively consumed content and is therefore heavily cached (12h). It is only used to give an overview of existing mirrors.

The mm-frontend-checkin01 server is only used for report_mirror check-ins. This is used by mirrors to report their status independent of the crawlers.

MirrorManager should automatically detect the new release version, and will create a new Version() object in the database. This is visible on the Version page in the web UI, and on https://admin.fedoraproject.org/mirrormanager/.

If the versioning scheme changes, it’s possible this will fail. If so, contact the Mirror Wrangler.

In the first week after the release MirrorManager still uses the files at fedora/linux/development/<version> and not at fedora/linux/releases/<version>

Once enough mirrors have picked up the files in the release directory following script (on mm-backend01) can be used to change the paths in MirrorManager:

Once the files of an EOL release have been copied to the archive directory tree and enough mirrors have picked the files up at the archive location there is also a script to adapt those paths in MirrorManager’s database:

Every hour at :55 after the hour, mm-backend01 generates a pkl file with all the current mirrormanager information in it and syncs it to proxies and mirrorlist-servers. Each proxy accepts requests to mirrors.fedoraproject.org on apache, then uses haproxy to determine what backend will reply. There are 2 containers defined on each proxy: mirrorlist1 and mirrorlist2. haproxy will look for those first, then fall back to any of the mirrorlist servers defined over the vpn.

At :15 after the hour, a script runs on all proxies: /usr/local/bin/restart-mirrorlist-containers This script starts up mirrorlist2 container, makes sure it can process requests and then if so, restarts mirrorlist1 container with the new pkl data. If not, mirrorlist1 keeps running with the old data. During this process at least one (with mirrorlists servers as backup) server is processing requests so users see no issues.

mirrorlist-containers log to /var/log/mirrormanager/mirrorlist\{1|2}/ on the host proxy server.