Command Reference Guide

3Com Router 3000 Ethernet Family
Command Reference Guide Chapter 11 NAT Configuration Commands
3Com Corporation
11-12
global-addr: An IP address provided for the outside to access (a legal IP address).
global-port: A service port number provided for the outside to access. If ignored, its
value shall be the same with the host-port’s value.
host-addr: IP address of the server in internal LAN.
host-port: Service port number provided for a server in the range of 0 to 65535, and the
common used port numbers are replaced by key words. For example, www service port
number is 80, which can also be represented by www. ftp service port number is 21,
and ftp can also stands for it. If the inside-port is 0, it indicates that all the types of
services can be provided and the key word any can be used to stand for it in this
situation. If the parameter is not configured, it is considered as the case of any, which is
the same as that there is a static connection between global-addr and host-addr. When
the host-port is configured as any, the global-port also should be any, otherwise the
configuration is illegal.
global-port1, global-port2: Specifies a port range through two port numbers, forming a
corresponding relation with the internal host address range. global-port2 must be larger
than global-port1.
host-addr1, host-addr2: Defines a group of consecutive address ranges, which
respectively one-to-one matches the port ranges defined above. host-addr2 must be
bigger than host-addr1. The number of the address ranges should be the same as the
number of ports defined by global-port1 and global-port2.
pro-type: The protocol type carried by IP, possibly being a protocol ID, or a key word as
a substitution. For example: icmp (its protocol ID is 1), tcp (its protocol ID is 6), udp (its
protocol ID is 17).
Description
Use the nat server command to define a mapping table for internal servers. Users can
access the internal server with the address and port as host-addr and host-port
respectively through the address port defined by global-addr and global-port.
Use the undo nat server command to remove the mapping table.
Through this command, you can configure some internal network servers for outside
use. The internal server can locate in the ordinary private network or in MPLS VPN. For
example, www, ftp, telnet, kpop3, dns and so on.
Up to 256 internal server conversion commands can be configured on one interface
and at most 4096 internal servers can be configured on one interface. Up to 1024
internal server conversion commands can be configured in one system. If the nat
servers are configured in the form of port range (that is, specify a port range through
configuring global-port1 and global-port2, forming a corresponding relation with the
address range of the internal hosts), then the number of internal servers will be the
same as that of the ports configured, and the max number of them are also 4096.