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DNS cache

pihole-FTL offers an efficient DNS cache that helps speed up your Internet experience. This DNS cache is part of the embedded dnsmasq server. Setting the cache size to zero disables caching. The DNS TTL value is used for determining the caching period. pihole-FTL clears its cache on receiving SIGHUP.

Cache metrics

The Settings page (System panel, FTL table) gives live information about the cache usage. It obtains its information from http://pi.hole/admin/api.php?getCacheInfo.

DNS cache size

Size of the DNS domain cache, defaulting to 10,000 entries. You typically specify this number directly in /etc/dnsmasq.d/01-pihole.conf. It is the number of entries that can be actively cached at the same time. There is no benefit in enlarging this number except if the DNS cache evictions count is larger than zero.

This information may also be queried using dig +short chaos txt cachesize.bind

DNS cache insertions

Number of total insertions into the cache. This number can be substantially larger than DNS cache size as expiring cache entries naturally make room for new insertions over time. Each lookup with a non-zero TTL will be cached.

This information may also be queried using dig +short chaos txt insertions.bind

DNS cache evictions

Number of cache entries that had to be removed although the corresponding entries were not expired. Old cache entries get removed if the cache is full to make space for more recent domains. The cache size should be increased when this number is larger than zero.

This information may also be queried using dig +short chaos txt evictions.bind