system.dns_cache

Querying in ClickHouse Cloud

The data in this system table is held locally on each node in ClickHouse Cloud. Obtaining a complete view of all data, therefore, requires the clusterAllReplicas function. See here for further details.

Contains information about cached DNS records.

Columns:

• hostname (String) — cached hostname
• ip_address (String) — ip address for the hostname
• ip_family (Enum) — family of the ip address, possible values:
  • 'IPv4'
  • 'IPv6'
  • 'UNIX_LOCAL'
• cached_at (DateTime) - when the record was cached

Example

Query:

Result:

hostname	ip_address	ip_family	cached_at
localhost	::1	IPv6	2024-02-11 17:04:40
localhost	127.0.0.1	IPv4	2024-02-11 17:04:40

See also

• disable_internal_dns_cache setting
• dns_cache_max_entries setting
• dns_cache_update_period setting
• dns_max_consecutive_failures setting