Installing and Administering Internet Services

Chapter 5 233
Configuring TFTP and BOOTP Servers
Adding Client or Relay Information
Table 5-2 lists the tags most commonly used to define the relay
parameters. For more information on these and the other tags available,
type man 1M bootpd.
A relay entry can contain relay parameters for an individual system or
for a group of systems. If a BOOTP client does not have an individual
entry in the BOOTP server’s /etc/bootptab file, the group relay entries
are searched. The first group relay entry that matches the BOOTP client
is used.
sm The subnet mask for the client’s network.
tc Specifies previously-listed entry that contains tag values that are shared by
several client entries.
vm The format of the vendor extensions on the bootrequest and bootreply.
Possible values are auto (the bootreply uses the format used in the
bootrequest), rfc1048 (the most commonly used format, described in RFC
1048), and cmu (another format used by some BOOTP clients). If you do not
specify the vm tag, the bootreply will use the format sent by the client in the
bootrequest.
Table 5-1 Tags for Defining Client Options in bootptab
Table 5-2 Tags for Defining Relay Options in bootptab
bp List of boot servers to which the client’s bootrequests will be forwarded. The
list can contain individual IP addresses, hostnames, or network broadcast
addresses.
ha Client’s hardware address.
hm Mask for the link level address. This value is ANDed with the ha value to
determine a match for a group relay entry. If this tag is specified, the ha and
ht tags must also be specified.
hp Maximum number of hops for the entry. Default is 4.
ht Client’s hardware type. See the bootp man page for supported hardware
types and the corresponding values. If used, this tag must precede the ha tag.
tc Specifies previously-listed entry that contains tag values that are shared by
several client entries.