Cabletron Systems STS16-20D, STS16-20R manual BootP Requests and Parameters

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BootP Requests and Parameters

When using BootP to determine its IP address, the SmartStack STS16-20D/STS16- 20R repeats BootP requests at regular intervals, beginning at one second each and eventually decreasing to every five minutes over time until it receives a valid reply. If the IP display for the VLAN is accessed from the console (or via Telnet from another VLAN) during that time, the SmartStack STS16-20D/STS16-20R may cease using BootP if the parameters are set (on menu exit) in such a way that BootP would no longer be necessary - for instance, if the IP state is switched from BootP Always to IP-Disabledor if an IP address different from 0.0.0.0 or 192.0.2.1 is specified in any IP state.

Once the SmartStack STS16-20D/STS16-20R has stopped sending BootP requests on a VLAN, it does not restart sending requests on that VLAN and does not recognize BootP responses on that VLAN unless the VLAN enters a state where it would be necessary again.

Besides the switch's IP address, several other parameters in a BootP response are also recognized and recorded in NVRAM, when received in the same response:

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Default Gateway (see the note on this page)

Subnet Mask

TFTP Main Code File Name

TFTP Server Address (only recognized if the Bootfile name is present)

One other parameter, the TFTP VLAN, is inferred whenever a TFTP Bootfile name is present in the BootP response. That is, if the SmartStack STS16-20D/STS16-20R receives a BootP response that specifies a TFTP Bootfile name, the SmartStack STS16-20D/STS16-20R automatically records the VLAN on which the response was received as the TFTP VLAN number. Therefore, the bootfile name should not be specified on a VLAN from which the TFTP server cannot be accessed, either directly or through the VLAN’s default gateway (if one exists). More information on TFTP is available under the section “TFTP” on page 149 in this chapter.

➽Note: The default gateway accepted is the first one in the list of routers whose net/ subnet address is the same as that of the IP address specified. If no routers are specified or if none qualify, the gateway address for the VLAN will be zeroed out and recorded as such in NVRAM when the IP screen is exited.

SmartStack STS16-20D/STS16-20R Token Ring Switches Installation and User Guide Switch Configuration