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ptr_host

local domain = kumo.dns.ptr_host(IP)
Since: Dev Builds Only

The functionality described in this section requires a dev build of KumoMTA. You can obtain a dev build by following the instructions in the Installation section.

Given an IP address in either V4 or V6 format as the input, returns the reversed address plus appropriate top level domain suitable for performing a reverse lookup.

This function is purely local string manipulation; no actual DNS queries are performed.

You will typically use lookup_ptr to perform an actual PTR lookup; this function is a utility function for the cases where you're doing something unusual.

print(kumo.dns.ptr_host '127.0.0.1')
-- prints out:
-- 1.0.0.127.in-addr.arpa

print(kumo.dns.ptr_host '::1')
-- prints out:
-- 1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa