266 Rockwell Automation Publication 1783-UM007G-EN-P - February 2017
Chapter 7 Configure Switch Features
6. In the Gateway Translation area, click Add Row, complete the fields, and
click Save.
The gateway translation enables devices on the public subnet to
communicate with devices on the private subnet.
7. (Optional). To configure traffic permits and packet fixups, see
Configure Traffic Permits and Fixups on page 273.
8. Click Submit.
Public IP Address Type a public IP address:
• To translate one address, type a unique public address to represent the device.
• To translate a range of addresses, type the first address in the range of sequential addresses.
• To translate addresses in a subnet, type a unique, starting public address to represent the devices. This address must correspond to the size of the subnet
mask to translate.
Subnet Mask Starting Public Subnet Address
255.255.0.0 The last two octets must end in 0.
EXAMPLE: 10.200.0.0
255.255.255.0 The last octet must end in 0.
EXAMPLE: 10.200.1.0.
255.255.255.128 The last octet must end in 0 or 128.
EXAMPLE: 10.200.1.0 or 10.200.1.128
255.255.255.192 The last octet must end in one of the following: 0, 64, 128, 192.
EXAMPLE: 10.200.1.64
255.255.255.224 The last octet must end in one of the following: 0, 32, 64, 96, 128, 160, 192, 224.
EXAMPLE: 10.200.1.32
255.255.255.240 The last octet must end in one of the following: 0, 16, 32, 48, 64, 80, 96, 112, 128, 144, 160, 176, 192, 208, 224, 240.
EXAMPLE: 10.200.1.16
Type Choose one of these values:
• Single—Translate one address.
• Range—Translate a range of addresses.
• Subnet—Translate all addresses in the private subnet or a portion of the private subnet.
Range Type the number of addresses to translate. This field is available only if you choose Range in the Type field.
Valid values: 2…128
Default value = 1
IMPORTANT: Each address in the range counts as one translation entry. The switch supports a maximum of 128 translation entries.
Subnet Mask Type the subnet mask for the addresses to translate.
Valid values:
• Class B: 255.255.0.0
• Class C: 255.255.255.0
• Portion of Class C:
– 255.255.255.128 (provides 128 addresses per translation entry)
– 255.255.255.192 (provides 64 addresses per translation entry)
– 255.255.255.224 (provides 32 addresses per translation entry)
– 255.255.255.240 (provides 16 addresses per translation entry)
Field Description
Field Description
Public Type the default gateway address of the Layer 3 switch or router that is connected to the
uplink port of the switch.
Private Type a unique IP address to represent the Layer 3 switch or router on the private network.