Sitemap Caching
The Sitemap
plug-in's sitemaps are potentially risky targets for denial of service
attacks, since they are dynamically generated. A continuous stream of
requests to a sitemap will quickly result in an unmanageable load on the
servers. It is therefore vitally important to place the sitemaps behind
a cache server. Responses from the sitemap service include
Cache-Control
response headers containing
s-maxage
directives specifying how long the sitemaps
are to be cached.
The default Cache-Control
settings included in
the headers are:
-
Aggregated sitemap:
public, s-maxage=86400
-
Update sitemap:
public, s-maxage=300
It is important to either ensure that your cache server is respecting these settings, or else set up similar caching rules manually using the cache server's administration interface.