DNS Proxy Integration

Feature Summary and Revision History

Summary Data

Table 1. Summary Data

Applicable Product(s) or Functional Area

SMF

Applicable Platform(s)

SMI

Feature Default Setting

Disabled – Configuration Required

Related Changes in this Release

Not Applicable

Related Documentation

Not Applicable

Revision History

Table 2. Revision History

Revision Details

Release

First introduced.

Pre-2020.02.0

Feature Description

The Domain Name System (DNS) is a network of servers that translates numeric IP addresses into readable, hierarchical Internet addresses, and vice-versa. The DNS Proxy allows you to configure the proxy servers (one or more) for resolving the host names. The DNS queries – for resolving host names to their IP addresses – are sent to the configured DNS servers through the DNS proxy servers.

The DNS proxy feature is integrated in the SMF network function.

How it Works

The DNS proxy feature is integrated in the SMF cluster. For sending the list of host names to resolve the DNS Proxy server, the SMF Client Library calls the smfdnsclnt.DNSLookupRequest() Request. The DNS Proxy server forwards the request to the Open source DNS package for host name to IP address resolution.

Figure 1. DNS Proxy Feature Integration

Call Flows

The following call flow illustrates the communication between the DNS client and the Proxy server.

Figure 2. DNS Client and Proxy Server Communication Call Flow

Configuring the DNS Proxy Feature

This section describes how to configure the DNS proxy feature.

Configuring the DNS proxy feature involves the following steps:

  1. Configuring SMF DNS proxy replica

  2. Configuring SMF DNS proxy

Configuring SMF DNS Proxy Replica

Use the following configuration to configure the SMF DNS proxy replica.


configure 
   k8 smf profile dns-proxy no-of-replicas integer  
   commit 
   end

NOTES:

  • k8 smf profile dns-proxy no-of-replicas integer : Specifies the number of replicas of the DNS proxy pod.

  • commit : Commits the configuration.

Configuring SMF DNS Proxy

Use the following configuration to configure the SMF DNS proxy feature.


configure 
   profile dns-proxy 
      timeout integer 
      query-type { ipv4v6 | ipv4 | ipv6 } 
      servers string  
      ip string  
      port integer 
      priority integer 
      protocol { tcp | udp } 
      commit

NOTES:

  • profile dns-proxy – Enters the DNS Proxy Configuration mode.

  • timeoutinteger – Specifies the client timeout value.

  • query-type – Specifies the DNS query type.

  • servers string – Specifies the name of the DNS server. For example, serv1.

  • ip string – Specifies the IP address of the DNS server.

  • port integer – Specifies the priority of the DNS server.

  • protocol – Specifies the protocol of the DNS server.

  • commit – Commits the configuration.

The following is an example configuration where two DNS servers – serv1 and serv2 – are configured:


show running-config profile dns-proxy profile1 
   query-type ipv4  
   timeout 5 
   servers serv1  
   ip 10.105.227.227 
   port 53  
   protocol tcp 
   priority 1 
   exit 
      servers serv2  
      ip 10.105.227.228  
      port 20  
      protocol udp  
      priority 2  
      exit 
exit