[Announce] Deprecating non-standard tile.osm.org URLs

[Grant Slater]

OpenStreetMap Devs,

After the 30th June 2012 a number of non-standard
tile.openstreetmap.org URLs will no longer function.

The only valid URL format is:
http://tile.openstreetmap.org/{z}/{x}/{y}.png

Valid host aliases are: a.tile.openstreetmap.org,
b.tile.openstreetmap.org, c.tile.openstreetmap.org, tile.osm.org,
a.tile.osm.org, b.tile.osm.org and c.tile.osm.org

Common non-standard URLs:
http://tile.openstreetmap.org//{z}/{x}/{y}.png
http://tile.openstreetmap.org/mapnik/{z}/{x}/{y}.png
http://tile.openstreetmap.org/mapnik_tiles/{z}/{x}/{y}.png
 ...and many more
All non-standard tile URLs will return 404 Not Found from the 30th June onwards.

The vast majority of websites and apps are using the valid URL format,
however you may wish to check that you are using the correct URL to
access tiles.

Please be aware that tile.openstreetmap.org has a usage policy:
http://wiki.openstreetmap.org/wiki/Tile_usage_policy
Mass scraping of tiles for offline usage or similar is NOT permitted
on this tile server.

Technical: The invalid URLs are poisoning our caches. Storage
re-writing is impractical due to the request rate. (>1000 tiles per
second)

Sincerely
Grant
Part of OpenStreetMap sysadmin team.