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What is mod tile and what is renderd?
mod_tile: An Apache 2 module to deliver map tiles. renderd: A daemon that renders map tiles using mapnik. Together they efficiently render and serve raster map tiles for example to use within a slippy map. The two consist of the classic raster tile stack from OpenStreetMap.org.
Where do I get the parameters for mod tile?
Lots of parameters are set in the render_config.h file and compiled into the mod_tile & renderd code. Ideally mod_tile should get all these parameters from some suitable module config options in the Apache config file. The renderd process would also need a config file or some command line options.
How is the rendering done in OpenStreetMap mod tile?
The rendering is implemented in a multithreaded process called renderd which opens either a unix or tcp socket and listens for requests to render tiles. It uses Mapnik to render tiles using the rendering rules defined in the configuration file /etc/renderd.conf. Its configuration also allows to specify the number of rendering threads.
How does mod tile work in Apache server?
An Apache module called mod_tile enhances the regular Apache file serving mechanisms to provide: 1) When tiles have expired it requests the rendering daemon to render (or re-render) the tile. 3) Prioritizes rendering requests depending on the available resources on the server and how out of date they are.
What is the zoom level for mod tile?
TileSetName is the name of the style sheet rendered. Z is the zoom level. [xxxxyyyy] is an 8 bit number, with the first 4 bits taken from the x coordinate and the second 4 bits taken from the y coordinate. This attempts to cluster 16×16 square of tiles together into a single sub directory for more efficient access patterns.
Why is mod tile used in OpenStreetMap server?
At the same time, its caching strategy allows for a high performance serving and can support several thousand requests per second. Mod_tile was originally written for serving the tiles of the main OSM map (Mapnik layer), but since is being used on a variety of different servers providing maps ontop of OpenStreetMap data.
What are some alternatives to Apache Tomcat software?
JBoss, Microsoft IIS, nginx, Jetty, and Flask are the most popular alternatives and competitors to Apache Tomcat.
How to install mod tile on multiple hosts?
You can increase the level of debugging using the LogLevel apache directive. If no log messages are shown check that you are accessing the correct virtual host – the new version of mod_tile is only installed on a single host by default. To install on multiple hosts either use ServerAlias or use the LoadTileConfigFile in each virtual host.
How to check if mod tile is installed on the correct host?
If this fails to happen check the http error log. You can increase the level of debugging using the LogLevel apache directive. If no log messages are shown check that you are accessing the correct virtual host – the new version of mod_tile is only installed on a single host by default.
How to install a tile server on mod _ tile?
Installing a tile server based on mod_tile requires a number of steps, some of which can be skipped depending on your needs: mod_tile uses Mapnik as a rendering backend. Therefore it is necessary to install it first and populate the PostGIS database with data first using osm2pgsql.
Where do I find the status of mod tile?
One way of doing this is my verifying that you get the mod_tile status page under http://your.server/mod_tile . The status page should give you a number of tiles mod_tile has served, split by zoom-level, their status codes and how many requests it has sent to the rendering back end.
How to check if mod tile is loaded into Apache?
Check if mod_tile is loaded into Apache. First you should check if mod_tile is correctly loaded into your apache. One way of doing this is my verifying that you get the mod_tile status page under http://your.server/mod_tile .