Perform reverse and forward DNS resolution.
Note: These functions are significantly slower than others in the ipaddress package.
Arguments
- x
ip_to_hostname()
: Anip_address
vectorhostname_to_ip()
: A character vector of hostnames
Value
ip_to_hostname()
: A character vectorip_to_hostname_all()
: A list of character vectorshostname_to_ip()
: Anip_address
vectorhostname_to_ip_all()
: A list ofip_address
vectors
Details
These functions require an internet connection. Before processing the input vector, we first check that a known hostname can be resolved. If this fails, an error is raised.
If DNS lookup cannot resolve an input, then NA
is returned for that input.
If an error occurs during DNS lookup, then a warning is emitted and NA
is
returned for that input.
DNS resolution performs a many-to-many mapping between IP addresses and
hostnames. For this reason, there are two versions of each function. The
regular version returns just the first value and the _all()
suffix version
returns all values.
See also
The base function nsl()
provides forward DNS resolution to IPv4 addresses,
but only on Unix-like systems.