Perl

Use Public DNS Servers (Google and Cloudfare)

See more DNS Examples

Demonstrates how to use Google and Cloudfare nameservers for all DNS lookups within Chilkat.

Note: This example requires Chilkat v9.5.0.96 or later.

Perl

use chilkat();

# The new Chilkat DNS class is a singleton that allows an applicaton to select 
# the DNS nameservers used throughout Chilkat.

# "singleton" means that all Chilkat DNS object instances work with a single
# copy of internal DNS settings that are application wide.

# Chilkat does DNS lookups internally whenever a domain name is passed to a Chilkat method, or when the domain
# name is part of a URL passed to a Chilkat method.  It could be in HTTP, Ftp2, SSH, IMAP, Socket, etc.

# This exampel will show how to use the Cloudfare and Google DNS servers.
# 
# Google Public DNS:
#   - Primary DNS: 8.8.8.8
#   - Secondary DNS: 8.8.4.4
#   Google Public DNS is known for its speed and reliability. It's operated by Google and is widely used by many internet users.

# Cloudfare Public DNS:
#   - Primary DNS: 1.1.1.1
#   - Secondary DNS: 1.0.0.1
#   Cloudfare Public DNS is also known for its speed and reliability, and is also widely used.

$dns = chilkat::CkDns->new();

# Indicate our TLS preference:
# 0: No TLS
# 1: Prefer TLS if possible
# 2: Require TLS
$dns->put_TlsPref(0);

# If you choose "No TLS", then all DNS requests will use UDP, or TCP for those requests with large responses.
# Choosing "No TLS" provides the fastest DNS lookups, and is generally what you're already doing.

# If you choose "Prefer TLS if possible", then Chilkat will use DNS over TLS for those nameservers that
# support TLS.

# If you choose "Require TLS", then Chilkat will ignore nameservers that don't support TLS,
# and all DNS communications will occur over private and secure TLS connections.

# When you specify a nameserver to be used, you'll tell Chilkat whether it supports DNS or not.
# Here' we're setting the nameservers to Google and Cloudfare.
# They both support TLS, but since we set our TLS preference = 0, Chilkat will not use TLS.
# (If we set our TLS preference equal to 1 or 2, then Chilkat will use TLS for Google and Cloudfare DNS.)

# First, make sure we remove all existing nameservers.
$dns->RemoveAllNameservers();

# Add the Google and Cloudfare nameservers.
$supportsTls = 1;
$dns->AddNameserver("1.1.1.1",$supportsTls);
$dns->AddNameserver("8.8.8.8",$supportsTls);
$dns->AddNameserver("1.0.0.1",$supportsTls);
$dns->AddNameserver("8.8.4.4",$supportsTls);

# That's it.  Now all DNS lookups in Chilkat will use the above nameservers.