Example: Configuring DHCP and DHCPv6 Relay Agent Group-Level Selective Traffic Processing

Requirements

• MX Series 3D Universal Edge Routers or PTX Series Packet Transport Switches
• Junos OS Release 12.3 or later.

• Configure DHCPv6 relay agent.

  See Extended DHCP Relay Agent Overview and DHCPv6 Relay Agent Overview.

• Configure the DHCPv6 named interface groups used for the configuration.

  See Grouping Interfaces with Common DHCP Configurations.

• Configure the DHCPv6 server groups used for the processing actions.

  See Grouping Interfaces with Common DHCP Configurations.

Overview

In this example, you configure group-level DHCPv6 relay agent named interface support for selective processing of client packets based on DHCPv6 option strings. To configure selective processing, you perform the following procedures:

1. Identify the client traffic—Specify the DHCPv6 option that DHCPv6 relay agent uses to identify the client traffic you want to process. The DHCPv6 option you specify matches the option in the client traffic.
2. Configure the default action—Specify the default processing action, which DHCPv6 relay uses for identified client traffic that does not satisfy any configured match criteria.
3. Create match filters and associate an action with each filter—Specify match criteria that filters the client traffic. The criteria can be an exact match or a partial match with the DHCPv6 option string in the client traffic. Associate a processing action with each match criteria.

Configuration

To configure group-level DHCPv6 relay agent selective processing based on DHCPv6 option information, perform these tasks:

• Configuring a DHCPv6 Relay Agent Named Interface Group To Selectively Process Client Traffic Based on DHCPv6 Option Strings
• Results

CLI Quick Configuration

To quickly configure this example, copy the following commands, paste them in a text file, remove any line breaks, change any details necessary to match your network configuration, and then copy and paste the command into the CLI at the [edit] hierarchy level. The quick configuration assumes that the named interface group and the DHCP server groups have been previously configured.

Configuring a DHCPv6 Relay Agent Named Interface Group To Selectively Process Client Traffic Based on DHCPv6 Option Strings

Step-by-Step Procedure

1. Specify that you want to configure DHCPv6 relay agent support.
   [edit forwarding-options]user@host# edit dhcp-relay dhcpv6
2. Specify that you want to configure group-level DHCPv6 relay agent support.
   [edit forwarding-options dhcp-relay dhcpv6]user@host# edit group groupv6-east-27
3. Specify the DHCPv6 option number that DHCPv6 relay agent uses to identify incoming client traffic.
   [edit forwarding-options dhcp-relay dhcpv6 group groupv6-east-27]user@host# set relay-option option-number 15
4. Configure the default action, which DHCPv6 relay agent uses when the incoming client traffic does not satisfy any configured match criteria.
   [edit forwarding-options dhcp-relay dhcpv6 group groupv6-east-27]user@host# set relay-option default-action relay-server-group relayserver-def-4
5. Configure an exact match condition and associated action that DHCPv6 relay uses to process the identified client traffic.
   [edit forwarding-options dhcp-relay dhcpv6 group groupv6-east-27]user@host# set relay-option equals ascii triple-gold relay-server-group relayserver-triple-8
6. Configure a second exact match condition and associated action that DHCPv6 relay uses to process client traffic.
   [edit forwarding-options dhcp-relay dhcpv6 group groupv6-east-27]user@host# set relay-option equals ascii triple-silver relay-server-group relayserver-triple-23
7. Configure a partial match criteria and associated action that DHCPv6 relay uses to process client traffic.
   [edit forwarding-options dhcp-relay dhcpv6 group groupv6-east-27]user@host# set relay-option starts-with ascii single relay-server-group relayserver-1-aa

Results

From configuration mode, confirm the results of your configuration by issuing the show statement at the [edit forwarding-options dhcp] hierarchy level. If the output does not display the intended configuration, repeat the configuration instructions in this example to correct it.

If you are done configuring the device, enter commit from configuration mode.

Verification

To verify the status of DHCPv6 relay agent selective traffic processing, perform this task:

• Verifying the Status of DHCPv6 Relay Agent Selective Traffic Processing

Verifying the Status of DHCPv6 Relay Agent Selective Traffic Processing

Purpose

Verify the DHCPv6 relay agent selective traffic processing status.

Action

DHCPv6 Packets dropped:
    Total                       0

Messages received:
    DHCPV6_DECLINE              0
    DHCPV6_SOLICIT              10
    DHCPV6_INFORMATION_REQUEST  0
    DHCPV6_RELEASE              0
    DHCPV6_REQUEST              10
    DHCPV6_CONFIRM              0
    DHCPV6_RENEW                0
    DHCPV6_REBIND               0
    DHCPV6_RELAY_REPL           0

Messages sent:
    DHCPV6_ADVERTISE            0
    DHCPV6_REPLY                0
    DHCPV6_RECONFIGURE          0
    DHCPV6_RELAY_FORW           0

Packets forwarded:
    Total                       4
    FWD REQUEST                 2
    FWD REPLY                   2

Meaning

The Packets forwarded field in the show dhcpv6 relay statistics command output displays the number of client packets that have been forwarded as a result of the selective traffic processing configuration. In this example, the output indicates the total number of packets that DHCPv6 relay agent has forwarded, as well as a breakdown for the number of FWD REQUEST and FWD REPLY packets forwarded.