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Chapter2 Installingthe Model5399 Remote Access ConcentratorModule
NortelNetworks 5399 Access Switch HardwareInstallation Guide
When the Remote Access Concentrator receives a BO OTP response with
the sm,gw,andipset, it sets the respective parameters: subnet_mask,
load_dump_gateway,andinet_addr.The Vendor Magic Cookie must
be set to auto. This indicates that bootpd should respond tothe client
(Model 5399 Remote AccessConcentrator in this case) with whatever
formatthe client requests; the Model 5399 Remote Access Concentrator
(client) always makes requestswith the Vendor Magic Cookie set to
99.130.83.99.
The bootpd adds the addressof the host on which it is running as the
ServerAddress in thebootpresponse message. The ROMs use the Server
Addressas the preferred load host and store it in the pref_load_addr
parameter.
The host running bootpd (thepreferred load host) must also be
running erpcdor tftpd.
RARP
Ifthe Remote Access Concentrator does not receive a successful BOOTP
response, it uses RARP to get the boot information. For a successful
RARP retrieval, TCP/IP must be runningon a host that is on the same
subnetas the Remote Access Concentrator,and the host’s ARP tablem ust
be initialized withthe R emoteA ccessConcentrator’s Internet and
Ethernet addresses (see the arp man pagefor arp –s).
The only boot information thatR ARP providesis the Remote Access
Concentrator’sInternet address. The ROMs save this information in the
inet_addrpa rameter.The ROMs use default information for the subnet
maskand preferred load host. This means the ROMs will broadcast their
requests.