etc/apache2/mod_tile.conf

# Based on https://github.com/openstreetmap/mod_tile/blob/master/mod_tile.conf

# Specify the default base storage path for where tiles live. A number of different storage backends
# are available, that can be used for storing tiles.  Currently these are a file based storage, a memcached
# based storage and a RADOS based storage.
# The file based storage uses a simple file path as its storage path ( /path/to/tiledir )
# The RADOS based storage takes a location to the rados config file and a pool name ( rados://poolname/path/to/ceph.conf )
# The memcached based storage currently has no configuration options and always connects to memcached on localhost ( memcached:// )
#
# The storage path can be overwritten on a style by style basis from the style TileConfigFile
ModTileTileDir /k/osm/tirex/tiles

# You can either manually configure each tile set with the default png extension and mimetype
#AddTileConfig /folder/ TileSetName

# or manually configure each tile set, specifying the file extension
#AddTileMimeConfig /folder/ TileSetName js

# or load all the tile sets defined in the configuration file into this virtual host.
# Some tile set specific configuration parameters can only be specified via the configuration file option
LoadTileConfigFile /etc/tirex/mod_tile.conf

# Specify if mod_tile should keep tile delivery stats, which can be accessed from the URL /mod_tile
# The default is On. As keeping stats needs to take a lock, this might have some performance impact,
# but for nearly all intents and purposes this should be negligable ans so it is safe to keep this turned on.
ModTileEnableStats On

# Turns on bulk mode. In bulk mode, mod_tile does not request any dirty tiles to be rerendered. Missing tiles
# are always requested in the lowest priority. The default is Off.
ModTileBulkMode Off

# Timeout before giving up for a tile to be rendered
ModTileRequestTimeout 3

# Timeout before giving up for a tile to be rendered that is otherwise missing
ModTileMissingRequestTimeout 10

# If tile is out of date, don't re-render it if past this load threshold (users gets old tile)
ModTileMaxLoadOld 16

# If tile is missing, don't render it if past this load threshold (user gets 404 error)
ModTileMaxLoadMissing 50

# Sets how old an expired tile has to be to be considered very old and therefore get elevated priority in rendering
ModTileVeryOldThreshold 31536000000000

# Unix domain socket where we connect to the rendering daemon
#ModTileRenderdSocketName /var/run/renderd/renderd.sock
ModTileRenderdSocketName /var/lib/tirex/modtile.sock

# Alternatively you can use a TCP socket to connect to renderd. The first part
# is the location of the renderd server and the second is the port to connect to.
#   ModTileRenderdSocketAddr renderd.mydomain.com 7653

##
## Options controlling the cache proxy expiry headers. All values are in seconds.
##
## Caching is both important to reduce the load and bandwidth of the server, as
## well as reduce the load time for the user. The site loads fastest if tiles can be
## taken from the users browser cache and no round trip through the internet is needed.
## With minutely or hourly updates, however there is a trade-off between cacheability
## and freshness. As one can't predict the future, these are only heuristics, that
## need tuning.
## If there is a known update schedule such as only using weekly planet dumps to update the db,
## this can also be taken into account through the constant PLANET_INTERVAL in render_config.h
## but requires a recompile of mod_tile

## The values in this sample configuration are not the same as the defaults
## that apply if the config settings are left out. The defaults are more conservative
## and disable most of the heuristics.


##
## Caching is always a trade-off between being up to date and reducing server load or
## client side latency and bandwidth requirements. Under some conditions, like poor
## network conditions it might be more important to have good caching rather than the latest tiles.
## Therefor the following config options allow to set a special hostheader for which the caching
## behaviour is different to the normal heuristics
##
## The CacheExtended parameters overwrite all other caching parameters (including CacheDurationMax)
## for tiles being requested via the hostname CacheExtendedHostname
#ModTileCacheExtendedHostname cache.tile.openstreetmap.org
#ModTileCacheExtendedDuration 2592000

# Upper bound on the length a tile will be set cacheable, which takes
# precedence over other settings of cacheing
ModTileCacheDurationMax 604800

# Sets the time tiles can be cached for that are known to by outdated and have been
# sent to renderd to be rerendered. This should be set to a value corresponding
# roughly to how long it will take renderd to get through its queue. There is an additional
# fuzz factor on top of this to not have all tiles expire at the same time
ModTileCacheDurationDirty 900

# Specify the minimum time mod_tile will set the cache expiry to for fresh tiles. There
# is an additional fuzz factor of between 0 and 3 hours on top of this.
ModTileCacheDurationMinimum 10800

# Lower zoom levels are less likely to change noticeable, so these could be cached for longer
# without users noticing much.
# The heuristic offers three levels of zoom, Low, Medium and High, for which different minimum
# cacheing times can be specified.

#Specify the zoom level below  which Medium starts and the time in seconds for which they can be cached
ModTileCacheDurationMediumZoom 13 86400

#Specify the zoom level below which Low starts and the time in seconds for which they can be cached
ModTileCacheDurationLowZoom 9 518400

# A further heuristic to determine cacheing times is when was the last time a tile has changed.
# If it hasn't changed for a while, it is less likely to change in the immediate future, so the
# tiles can be cached for longer.
# For example, if the factor is 0.20 and the tile hasn't changed in the last 5 days, it can be cached
# for up to one day without having to re-validate.
ModTileCacheLastModifiedFactor 0.20

## Tile Throttling
## Tile scrapers can often download large numbers of tiles and overly straining tileserver resources
## mod_tile therefore offers the ability to automatically throttle requests from ip addresses that have
## requested a lot of tiles.
## The mechanism uses a token bucket approach to shape traffic. I.e. there is an initial pool of n tiles
## per ip that can be requested arbitrarily fast. After that this pool gets filled up at a constant rate
## The algorithm has two metrics. One based on overall tiles served to an ip address and a second one based on
## the number of requests to renderd / tirex to render a new tile.

## Overall enable or disable tile throttling
ModTileEnableTileThrottling Off
# Specify if you want to use the connecting IP for throtteling, or use the X-Forwarded-For header to determin the
# IP address to be used for tile throttling. This can be useful if you have a reverse proxy / http accellerator
# in front of your tile server.
# 0 - don't use X-Forward-For and allways use the IP that apache sees
# 1 - use the client IP address, i.e. the first entry in the X-Forwarded-For list. This works through a cascade of proxies.
#     However, as the X-Forwarded-For is written by the client this is open to manipulation and can be used to circumvent the throttling
# 2 - use the last specified IP in the X-Forwarded-For list. If you know all requests come through a reverse proxy
#     that adds an X-Forwarded-For header, you can trust this IP to be the IP the reverse proxy saw for the request
ModTileEnableTileThrottlingXForward 0
## Parameters (poolsize in tiles and topup rate in tiles per second) for throttling tile serving.
ModTileThrottlingTiles 10000 1
## Parameters (poolsize in tiles and topup rate in tiles per second) for throttling render requests.
ModTileThrottlingRenders 128 0.2

###
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# increase the log level for more detailed information
    LogLevel debug