Configuring Dns Mapping; Configuring Twice Nat - Huawei S9700 Series Configuration Manual

S9700 Core Routing Switch
Configuration Guide - SPU

3.3.10 Configuring DNS Mapping

A private network may deploy different servers such as FTP servers and web servers, but has
no DNS server deployed. If hosts on the private network need to differentiate and access servers
using domain names, configure DNS mapping.
Procedure
Step 1 Run:
system-view
The system view is displayed.
Step 2 Run:
nat dns-map domain-name global-address global-port { tcp | udp }
The mapping from a domain name to a public IP address, port number, and protocol type is
configured.
Up to 64 mapping entries can be configured on the SPU.
Step 3 Run:
nat alg { all | dns | ftp
The NAT ALG function is enabled for DNS.
The NAT ALG function allows hosts on a private network to access servers on the private
network through the external DNS server.
----End

3.3.11 Configuring Twice NAT

Twice NAT translates both the source and destination IP addresses of a data packet. It applies
to the situation where IP addresses of internal hosts and external hosts overlap.
Context
When IP addresses of internal hosts and external hosts overlap, configure the mapping between
the overlapping address pool and the temporary address pool. Then the overlapping address is
translated to a unique temporary address and packets can be forwarded correctly. In addition,
configure outbound NAT to implement twice NAT.
Procedure
Step 1 Run:
system-view
The system view is displayed.
Step 2 Run:
nat overlap-address map-index overlappool-startaddress temppool-startaddress pool-
length length [ inside-vpn-instance inside-vpn-instance-name ]
Issue 01 (2012-03-15)
| rtsp | sip } enable
CAUTION
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