PureBasic

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.

PureBasic

IncludeFile "CkDns.pb"

Procedure ChilkatExample()

    ; 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.i = CkDns::ckCreate()
    If dns.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ; Indicate our TLS preference:
    ; 0: No TLS
    ; 1: Prefer TLS if possible
    ; 2: Require TLS
    CkDns::setCkTlsPref(dns, 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.
    CkDns::ckRemoveAllNameservers(dns)

    ; Add the Google and Cloudfare nameservers.
    supportsTls.i = 1
    CkDns::ckAddNameserver(dns,"1.1.1.1",supportsTls)
    CkDns::ckAddNameserver(dns,"8.8.8.8",supportsTls)
    CkDns::ckAddNameserver(dns,"1.0.0.1",supportsTls)
    CkDns::ckAddNameserver(dns,"8.8.4.4",supportsTls)

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


    CkDns::ckDispose(dns)


    ProcedureReturn
EndProcedure