DHCP configuration file customization

There are various factors involved in customizing your DHCP configuration file.

Many networks include multiple client types; for example, a single network may include computers running a variety of operating systems, such as Windows, OS/2, Java™ OS, and UNIX. Each of these require unique vendor identifiers (the field used to identify the type of machine to the DHCP server). Java OS clients and IBM® Thin Client machines can require unique parameters such as bootfiles, and configuration options that need to be tailored specifically for them. Windows 95 computers do not handle Java-specific options well.

Machine-specific options can be encapsulated within vendor containers if the primary use for certain machines is based on the type of user for those machines. For instance, the development staff might use this operating system's clients for programming, the marketing staff might use the OS/2 clients, sales might use Java OS clients and IBM Thin Client machines, and accounting might use Windows 95 machines. Each of these user families might need different configuration options (different printers, name servers, or default web servers, and so forth). In this case, such options could be included in the vendor container, since each group uses a different machine type.

If the same machine type is used by multiple groups, placing the options within a subordinate class identifier instead, would allow your marketing managers, for example, to use a specific set of printers that other employees could not access.

vendor "AIX_CLIENT"
{
# No specific options, handles things based on class
}

vendor "OS/2 Client"
{
# No specific options, handles things based on class
}

vendor "Windows 95"
{ option 44 9.3.150.3          # Default NetBIOS Nameserver
}

vendor "Java OS"
{ bootstrapserver 9.3.150.4    # Default TFTP server for the Java OS boxes
  option 67 "javaos.bin"       # The bootfile of the Java OS box
}

vendor "IBM Thin Client"
{ bootstrapserver 9.3.150.5    # Default TFTP server for Thin Client boxes
  option 67 "thinos.bin"       # Default bootfile for the Thin Client boxes
}

subnet 9.3.149.0 255.255.255.0
{ option 3 9.3.149.1           # The default gateway for the subnet
  option 6 9.3.150.2           # This is the nameserver for the subnet
  class accounting 9.3.149.5-9.3.149.20
  {    	  # The accounting class is limited to address range 9.3.149.5-9.3.149.20
          # The printer for this group is also in this range, so it is excluded.
     exclude 9.3.149.15
     option 9 9.3.149.15       # The LPR server (print server)
     vendor "Windows 95"
     {
     option 9 deny              # This installation of Windows 95 does not support
                                # this printer, so the option is denied.
     }
  }
 . . .
}