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delay-advertise (DHCPv6)


Hierarchy Level


Delay sending a DHCPv6-advertise message to specified clients. The configured server sends the advertise message when the delay timer expires. If the client is already bound to another server when it receives this advertise message, the DHCPv6 server that delayed the message releases the client. You can change the delay value at any time, but the change applies only to clients from which a solicit is received after the change; the new value does not apply to clients for which the response is already delayed.

Configuring the delay on DHCPv6 local servers enables load-balancing among multiple local servers on the network. When a client sends a solicit message, the delay prevents more than one server from replying at the same time. The delay applies on a per-client basis. You can configure the clients affected based on DHCPv6 option 15 (user class identifier), option 16 (vendor class identifier), option 18 (interface identifier; ACI). or option 37 (ARI).

If the configured server receives a second solicit message from the client, that means that no other server has responded. In this case, the configured server immediately replies to the client. This behavior enables the server to act as a back-up for other servers on the network.



Value of the option expressed as an ASCII string.


Specify the DHCPv6 option received in the solicit message that is compared with the configured value on the local server.

  • option-15—DHCPv6 option 15, user class identifier.

  • option-16—DHCPv6 option 16, vendor class identifier.

  • option-18—DHCPv6 option 18, interface identifier, equivalent to the Agent Circuit ID.

  • option-37—DHCPv6 option 37, the Agent Remote ID.


Time delay between receiving DHCPv6 solicit message and responding to the client with an advertise message.

  • Range: 1 through 30

  • Default: 3


Specify that the received option value from the client must match the configured string.


Value of the option expressed as a hexadecimal.


Specify that the received option value from the client must not match the configured string.


Specify that the received option value from the client must start with the configured string.

Required Privilege Level

system—To view this statement in the configuration.

system-control—To add this statement to the configuration.

Release Information

Statement introduced in Junos OS Release 16.1R1.