unixdev.net


Switch to SpeakEasy.net DSL

The Modular Manual Browser

Home Page
Manual: (SunOS-5.10)
Page:
Section:
Apropos / Subsearch:
optional field

dhcp_inittab(4)                  File Formats                  dhcp_inittab(4)



NAME
       dhcp_inittab - information repository for DHCP options

DESCRIPTION
       The  /etc/dhcp/inittab file contains information about the Dynamic Host
       Configuration Protocol (DHCP) options, which are network  configuration
       parameters  passed  from  DHCP  servers  to  DHCP clients when a client
       machine uses DHCP. Since many  DHCP-related  commands  must  parse  and
       understand  these  DHCP options, this file serves as a central location
       where information about these options may be obtained.

       The DHCP inittab file provides three general pieces of information:

         o  A mnemonic alias, or symbol name,  for  each  option  number.  For
            instance,  option 12 is aliased to the name Hostname. This is use-
            ful for DHCP-related programs that require human interaction, such
            as dhcpinfo(1).

         o  Information about the syntax for each option. This includes infor-
            mation such as the type of the value, for example, whether it is a
            16-bit integer or an IP address.

         o  The policy for what options are visible to which DHCP-related pro-
            grams.


        The dhcp_inittab file can only be changed upon  system  upgrade.  Only
       additions of SITE options (or changes to same) will be preserved during
       upgrade.

       The VENDOR options defined here are intended for  use  by  the  Solaris
       DHCP  client  and DHCP management tools. The SUNW vendor space is owned
       by Sun, and changes are likely during upgrade. If you need to configure
       the  Solaris  DHCP  server to support the vendor options of a different
       client, see dhcptab(4) for details.

       Each DHCP option belongs to a certain category, which  roughly  defines
       the scope of the option; for instance, an option may only be understood
       by certain hosts within a given site, or it may be globally  understood
       by  all DHCP clients and servers. The following categories are defined;
       the category names are not case-sensitive:

       STANDARD        All client and server DHCP implementations agree on the
                       semantics.  These  are  administered  by  the  Internet
                       Assigned Numbers Authority (IANA).  These  options  are
                       numbered from 1 to 127.



       SITE            Within a specific site, all client and server implemen-
                       tations agree on the  semantics.  However,  at  another
                       site  the  type  and meaning of the option may be quite
                       different. These options are numbered from 128 to 254.



       VENDOR          Each vendor may define 254 options unique to that  ven-
                       dor.  The  vendor is identified within a DHCP packet by
                       the "Vendor Class" option, number 60. An option with  a
                       specific  numeric  identifier  belonging  to one vendor
                       will, in general, have a type and  semantics  different
                       from  that  of  a  different vendor. Vendor options are
                       "super-encapsulated" into the vendor field  number  43,
                       as defined in RFC 2132. The dhcp_inittab file only con-
                       tains   Sun  vendor  options.  Define  non-Sun   vendor
                       options in the dhcptab file.



       FIELD           This  category  allows  the  fixed fields within a DHCP
                       packet to be aliased to a mnemonic name  for  use  with
                       dhcpinfo(1).



       INTERNAL        This category is internal to the Solaris DHCP implemen-
                       tation and will not be further defined.



   DHCP inittab Format
       Data entries are written one per line and have seven fields; each entry
       provides  information  for  one  option.  Each  field is separated by a
       comma, except for the first and second, which are separated  by  white-
       space  (as  defined  in isspace(3C)). An entry cannot be continued onto
       another line. Blank lines and those whose first non-whitespace  charac-
       ter is '#' are ignored.

       The fields, in order, are:

         o  Mnemonic Identifier

            The  Mnemonic  Identifier  is a user-friendly alias for the option
            number; it is not case sensitive. This field must be  per-category
            unique  and  should  be  unique  across all categories. The option
            names in the STANDARD, SITE, and VENDOR spaces should not overlap,
            or  the  behavior  will be undefined. See Mnemonic Identifiers for
            Options section of this man page for descriptions  of  the  option
            names.

         o  Category (scope)

            The  Category  field  is  one of STANDARD, SITE, VENDOR, FIELD, or
            INTERNAL and identifies the scope in which the option falls.

         o  Option Number

            The Option Number is the number of this option when  it  is  in  a
            DHCP  packet.  This  field  should  be per-category unique and the
            STANDARD and SITE fields should not have overlapping  code  fields
            or the behavior is undefined.

         o  Data Type

            Data  Type is one of the following values, which are not case sen-
            sitive:


            Ascii           A printable character string



            Bool            Has no value. Scope limited to category limited to
                            INTERNAL.  Presence  of  an  option  of  this type
                            within a  Solaris  configuration  file  represents
                            TRUE, absence represents FALSE.



            Octet           An array of bytes



            Unumber8        An 8-bit unsigned integer



            Snumber8        An 8-bit signed integer



            Unumber16       A 16-bit unsigned integer



            Snumber16       A 16-bit signed integer



            Unumber32       A 32-bit unsigned integer



            Snumber32       A 32-bit signed integer



            Unumber64       A 64-bit unsigned integer



            Snumber64       A 64-bit signed integer



            Ip              An IP address


            The  data  type  field describes an indivisible unit of the option
            payload, using one of the values listed above.

         o  Granularity

            The Granularity field describes how many  "indivisible  units"  in
            the  option payload make up a whole value or item for this option.
            The value must be greater than zero (0) for any  data  type  other
            than Bool, in which case it must be zero (0).

         o  Maximum Number Of Items

            This  value specifies the maximum items of  Granularity which  are
            permissible in a definition using this symbol. For example,  there
            can only  be  one  IP  address specified for a subnet mask, so the
            Maximum number of            items in this case  is  one  (1).   A
            Maximum  value
             of zero (0) means that a variable number of items is permitted.

         o  Visibility

            The  Visibility  field  specifies which DHCP-related programs make
            use of this information, and should always be  defined  as  "sdmi"
            for newly added options.


   Mnemonic Identifiers for Options
       The  following table maps the mnemonic identifiers used in Solaris DHCP
       to RFC 2132 options:


       tab(); lw(1.395174i) lw(1.093222i)  lw(3.011604i).   SymbolCodeDescrip-
       tion   Subnet1T{   Subnet  Mask,  dotted  Internet  address  (IP).   T}
       UTCoffst2T{  Coordinated   Universal   time   offset   (seconds).    T}
       Router3List  of  Routers,  IP.   Timeserv4List  of RFC-868 servers, IP.
       IEN116ns5List of IEN 116 name servers, IP.  DNSserv6List  of  DNS  name
       servers,  IP.   Logserv7T{  List  of  MIT-LCS  UDP log servers, IP.  T}
       Cookie8List of RFC-865 cookie servers, IP.  Lprserv9T{ List of RFC-1179
       line  printer servers, IP.  T} Impress10List of Imagen Impress servers,
       IP.  Resource11T{ List of RFC-887 resource location  servers,  IP.   T}
       Hostname12T{  Client's  hostname,  value from hosts database.  T} Boot-
       size13T{ Number of 512 octet blocks in boot image,  NUMBER.   T}  Dump-
       file14T{  Path  where  core  image  should  be dumped, ASCII.  T} DNSd-
       main15DNS domain name,  ASCII.   Swapserv16Client's  swap  server,  IP.
       Rootpath17Client's  Root path, ASCII.  ExtendP18Extensions path, ASCII.
       IpFwdF19T{ IP Forwarding  Enable/Disable,  NUMBER.   T}  NLrouteF20Non-
       local  Source  Routing,  NUMBER.   PFilter21Policy  Filter, IP.  MaxIp-
       Siz22T{ Maximum datagram Reassembly Size, NUMBER.  T} IpTTL23T{ Default
       IP  Time to Live, (1=<x<=255), NUMBER.  T} PathTO24T{ RFC-1191 Path MTU
       Aging Timeout, NUMBER.  T} PathTbl25T{ RFC-1191 Path MTU Plateau Table,
       NUMBER.   T}  MTU26Interface MTU, x>=68, NUMBER.  SameMtuF27All Subnets
       are Local, NUMBER.  Broadcst28Broadcast Address, IP.  MaskDscF29Perform
       Mask   Discovery,  NUMBER.   MaskSupF30Mask  Supplier,  NUMBER.   RDis-
       cvyF31Perform Router Discovery, NUMBER.  RSolictS32Router  Solicitation
       Address,  IP.   StaticRt33T{  Static Route, Double IP (network router).
       T} TrailerF34Trailer Encapsulation, NUMBER.  ArpTimeO35ARP  Cache  Time
       out,  NUMBER.   EthEncap36Ethernet  Encapsulation, NUMBER.  TcpTTL37TCP
       Default Time to Live, NUMBER.  TcpKaInt38TCP Keepalive  Interval,  NUM-
       BER.   TcpKaGbF39TCP  Keepalive  Garbage, NUMBER.  NISdmain40NIS Domain
       name, ASCII.  NISservs41List of NIS servers, IP.  NTPservs42List of NTP
       servers,  IP.  NetBNms44List of NetBIOS Name servers, IP.  NetBDsts45T{
       List of NetBIOS Distribution servers, IP.  T} NetBNdT46T{ NetBIOS  Node
       type  (1=B-node,  2=P,  4=M,  8=H).  T} NetBScop47NetBIOS scope, ASCII.
       XFontSrv48List of X Window Font servers, IP.  XDispMgr49T{  List  of  X
       Window  Display managers, IP.  T} LeaseTim51T{ Lease Time Policy, (-1 =
       PERM), NUMBER.  T} Message56T{  Message  to  be  displayed  on  client,
       ASCII.   T}  T1Time58Renewal (T1) time, NUMBER.  T2Time59Rebinding (T2)
       time, NUMBER.  NW_dmain62NetWare/IP Domain Name,  ASCII.   NWIPOpts63T{
       NetWare/IP  Options,  OCTET  (unknown  type).   T} NIS+dom64NIS+ Domain
       name, ASCII.  NIS+serv65NIS+ servers, IP.  TFTPsrvN66TFTP server  host-
       name,   ASCII.    OptBootF67Optional   Bootfile   path,  ASCII.   MblI-
       PAgt68Mobile IP Home Agent, IP.   SMTPserv69T{  Simple  Mail  Transport
       Protocol  Server,  IP.   T}  POP3serv70T{  Post  Office Protocol (POP3)
       Server, IP.  T}  NNTPserv71T{  Network  News  Transport  Proto.  (NNTP)
       Server,  IP.   T}  WWWservs72Default  WorldWideWeb  Server,  IP.   Fin-
       gersv73Default  Finger  Server,  IP.   IRCservs74Internet  Relay   Chat
       Server,  IP.  STservs75StreetTalk Server, IP.  STDAservs76T{ StreetTalk
       Directory Assist. Server, IP.   T}  UserClas77User  class  information,
       ASCII.   SLP_DA78Directory agent, OCTET.  SLP_SS79Service scope, OCTET.
       AgentOpt82Agent circuit ID, OCTET.  FQDN89Fully Qualified Domain  Name,
       OCTET.  PXEarch93Client system architecture, NUMBER.  PXEnii94T{ Client
       Network Device Interface, OCTET.  T} PXEcid97T{ UUID/GUID-based  client
       indentifier,  OCTET.  T} BootFileN/AFile to Boot, ASCII.  BootPathN/AT{
       Boot path prefix to apply to client's requested boot file,  ASCII.   T}
       BootSrvAN/ABoot  Server,  IP.   BootSrvNN/ABoot Server Hostname, ASCII.
       EchoVCN/AT{  Echo  Vendor  Class  Identifier  Flag,  (Present=TRUE)  T}
       LeaseNegN/AT{  Lease is Negotiable Flag, (Present=TRUE) T} IncludeN/AT{
       Include listed macro values in this macro.  T}


EXAMPLES
       Example 1: Altering the DHCP inittab File

       In general, the DHCP inittab file should only be altered  to  add  SITE
       options.  If  other  options  are added, they will not be automatically
       carried forward when the system is upgraded. For instance:

       ipPairs    SITE, 132, IP, 2, 0, sdmi


       describes an option named ipPairs, that is in the SITE  category.  That
       is,  it  is  defined  by each individual site, and is  option code 132,
       which is of type IP Address, consisting  of a potentially infinite num-
       ber of pairs of IP addresses.

FILES
                 /etc/dhcp/inittab

ATTRIBUTES
       See attributes(5)  for descriptions of the following attributes:


       tab()     allbox;     cw(2.750000i)|    cw(2.750000i)    lw(2.750000i)|
       lw(2.750000i).   ATTRIBUTE  TYPEATTRIBUTE   VALUE   AvailabilitySUNWcsr
       Interface StabilityEvolving


SEE ALSO
       dhcpinfo(1),dhcpagent(1M),   isspace(3C),   dhcptab(4),  attributes(5),
       dhcp(5), dhcp_modules(5)

       System Administration Guide: IP Services

       Alexander, S., and R. Droms. RFC 2132, DHCP Options  and  BOOTP  Vendor
       Extensions. Network Working Group. March 1997.

       Droms, R.  RFC 2131, Dynamic Host Configuration Protocol. Network Work-
       ing Group. March 1997.



SunOS 5.10                        7 Jun 2001                   dhcp_inittab(4)