Enterasys Networks X-PeditionTM Dhcp Client Timeouts, Interaction with Remote Auto Install RAI

DHCP Client Services

Primary and secondary IP addresses on the same interface are not permitted within the same subnet nor are they allowed within the same subnets already occupied by other interfaces. Also, the primary IP address must be configured before any secondary address is configured. If the primary address is DHCP negotiated, its address and mask are unknown until a DHCP server supplies such addresses.

Interaction with Remote Auto Install (RAI)

When DHCP Client negotiation is conducted during the RAI operations, minor differences occur in comparison to how the functionality behaves otherwise. The Parameters Request List will contain the following:

•Subnet Mask

•Routers

•Domain Name Servers

•Host Name

•Bootfile Name

•TFTP Server Address

A timer starts when DHCP Client is created on an interface. Upon the timer’s expiration, DHCP Client shuts down, informing RAI that address negotiation has failed and, in this case, is never restarted. RAI then attempts auto install on other interfaces.

In addition to RAI obtaining the address/mask in conventional fashion, the following data is also obtained when available:

•hostname of the router - (Option 12)

•file name (in order of preference) - file field or Option 67 (Bootfile Name)

•IP address of the TFTP server (in order of preference) - Option 150 (TFTP Server address) or siaddr field

For more information on RAI, refer to “Managing the XSR” on page 2-1.

DHCP Client Timeouts

The XSR supports the following default FSM (Finite State Machine) timeouts:

Table 15-3 FSM Timeouts

Timeout	Default	Description
Retry interval	300 seconds	Interval to re-enter Initial State if no lease
Select interval	0 seconds (accepts	Interval to accumulate OFFER messages from different servers
	first valid response)
Reboot timeout	10 seconds	Interval to enter Initial State from Rebooting State if no ACK/NAK
		received
Initial interval	3 seconds	Exponential backoff period starting with this value
Backoff cutoff	15 seconds	Peak backoff period

XSR User’s Guide 15-7