LEGACY DHCP · ISC DHCP · DHCPv4

Legacy DHCP (ISC DHCP): Standard DHCPv4 Options

Search standard DHCPv4 options and review their option codes, descriptions, data types, support status, grammar, and example values.

Legacy DHCP (ISC DHCP): Standard DHCPv4 Options
1subnet-maskSpecifies the client's subnet mask. If not provided, the DHCP server defaults to the subnet mask in the subnet declaration, unless overridden by a subnet-mask option in scope for the assigned address.ipv4addressTrueTrueip-addressType : ipv4
Example : 1.1.1.1
2time-offsetSpecifies the offset of the client’s subnet in seconds from Coordinated Universal Time (UTC).int32TrueTrueint32Range : -2,147,483,648 to +2,147,483,647
Example : 12345
3routersSpecifies a list of IP addresses for routers on the client’s subnet. Routers should be listed in order of preference.ipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
4time-serversSpecifies a list of Time Servers available to the client. Time Servers are listed in order of preference.ipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
5ien116-name-serversSpecifies a list of Name Servers available to the client. Name Servers are listed in order of preference.ipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
6domain-name-serversSpecifies a list of Domain Name System (RFC 1035) name servers available to the client. Servers are listed in order of preference.ipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
7log-serversSpecifies a list of UDP log servers available to the client. Servers are listed in order of preference.ipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
8cookie-serversThe cookie server option specifies a list of RFC 865 cookie servers available to the client. Servers should be listed in order of preference.ipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
9lpr-serversSpecifies a list of Line Printer Servers available to the client. Servers are listed in order of preference.ipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
10impress-serversSpecifies a list of Imagen Impress Servers available to the client. Servers are listed in order of preference.ipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
11resource-location-serversSpecifies a list of Resource Location Servers available to the client. Servers are listed in order of preference.ipv4addressTrueTrueip-addressType : ipv4
Example : 1.1.1.1
12host-nameConfigures the host name string that can be assigned to the DHCP clients.quoted_stringTrueTruestringExample : host_name
13boot-sizeSpecifies the size of the boot file in 512 byte blocksuint16TrueTrueuint16Range : 0-65535
Example : 1024
14merit-dumpSpecifies the file path name to which the client should dump its core image in the event of a client crashquoted_stringTrueTruestringExample : string_value
15domain-nameSpecifies the domain name the client should use when resolving host names using the Domain Name System.quoted_stringTrueTruetextExample : example.com
16swap-serverSpecifies the IP address of the client Swap Server.ipv4addressTrueTrueip-addressType : ipv4
Example : 1.1.1.1
17root-pathSpecifies the path name (entered as an ASCII character string) that contains the client root disk.quoted_stringTrueTruetextExample : /home/path/dhcpd/
18extensions-pathSpecifies a file, retrievable through TFTP, that contains information that can be interpreted in the same way as the vendor-extension field within the BOOTP response, with the following exceptions:
1) the length of the file is unconstrained
2) all references to instances of this option in the file are ignored		quoted_stringTrueTruetextExample : path/dhcpd/
19ip-forwardingEnable/Disable IP packet forwardingflagTrueTrueflagvalues : true or false or on or off
Example : true
20non-local-source-routingEnable/Disable IP packet forwarding for packets specifying non-local source routes.flagTrueTrueflagvalues : true or false or on or off
Example : true
21policy-filterSpecifies Policy Filters for non-local source routing. The filters consist of a list of IP addresses and masks that specify destination/mask pairs with which to filter incoming source routes. Any source-routed datagram whose next-hop address does not match one of the filters should be discarded by the client. In other words, it specifies acceptable non-local next hops to which IP packets may be forwarded for packets specifying non-local source routes.ipv4addressTrueTrueip-address ip-address [, ip-address ip-address...]Type : ipv4
Example : 1.1.1.1 2.2.2.2 ,3.3.3.3 4.4.4.4,..,etc
22max-dgram-reassemblyThe maximum size datagram the client should be ready to reassemble specified as a 16-bit unsigned integeruint16TrueTrueuint16Range : 0-65535
Example : 1024
23default-ip-ttlDefault IP time to live value for use in outgoing packet IP header TTL fielduint8TrueTrueuint8Range : 0-255
Example : 1
24path-mtu-aging-timeoutThe timeout in seconds when performing path maximum transmission unit (MTU) discovery in accordance with RFC 1191; MTU discovery helps minimize packet fragmentation along the pathuint32TrueTrueuint32Range : 0-4,294,967,295
Example : 12345
25path-mtu-plateau-tableSpecifies a table listing MTU sizes to use when performing Path MTU Discovery. The table is formatted as a list of 16-bit unsigned integers, ordered from smallest to largest. The minimum MTU value cannot be smaller than 68.uint16TrueTrueuint16 [, uint6... ]Range : 0-65535
Example : 1024,1024,..,etc
26interface-mtuSpecifies the value of the Maximum Transmission Unit (MTU) to use on this interface. The minimum legal value for the MTU is 68.uint16TrueTrueuint16Range : 0-65535
Example : 1024
27all-subnets-localIndicates whether all subnets within the client's network use the same maximum transmission unit (MTU) as the local subnet to which the client is connected.flagTrueTrueflagvalues : true or false or on or off
Example : true
28broadcast-addressSpecifies the Broadcast Address in use on the client subnet.ipv4addressTrueTrueip-addressType : ipv4
Example : 1.1.1.1
29perform-mask-discoverySpecifies whether the client should perform subnet mask discovery or notflagTrueTrueflagvalues : true or false or on or off
Example : true
30mask-supplierSpecifies whether the client should respond to other clients performing mask discoveryflagTrueTrueflagvalues : true or false or on or off
Example : true
31router-discoverySpecifies whether the client should perform router discovery or notflagTrueTrueflagvalues : true or false or on or off
Example : true
32router-solicitation-addressSpecifies the address to which the client should transmit router solicitation requests.ipv4addressTrueTrueip-addressType : ipv4
Example : 1.1.1.1
33static-routesSpecifies a list of Static Routes that the client should install in its routing cache. If multiple routes to the same destination are specified, they are listed in descending order of priority. The routes consist of a list of IP address pairs. The first address is the destination address, and the second address is the router for the destination. Note that the default route (0.0.0.0) is an illegal destination for a static route.ipv4addressTrueTrueip-address ip-address [, ip-address ip-address...]Type : ipv4
Example : 1.1.1.1 2.2.2.2 ,3.3.3.3 4.4.4.4,..,etc
34trailer-encapsulationSpecifies whether the client should attempt to negotiate the use of layer 2 frame trailers (like headers but at the end of the frame payload) in ARP messagesflagTrueTrueflagvalues : true or false or on or off
Example : true
35arp-cache-timeoutThis option specifies the timeout in seconds for ARP cache entries.uint32TrueTrueuint32Range : 0-4,294,967,295
Example : 12345
36ethernet-encapsulationSpecifies whether the client should use Ethernet II or IEEE 802.3 on an Ethernet interfaceflagTrueTrueflagvalues : true or false or on or off
Example : true
37default-tcp-ttlDefault TCP time to live valueuint8TrueTrueuint8Range : 0-255
Example : 1
38tcp-keepalive-intervalTCP keepalive interval in secondsuint32TrueTrueuint32Range : 0-4,294,967,295
Example : 12345
39tcp-keepalive-garbageSpecifies whether the client should send an octet of garbage within TCP keepalive messages for compatibility with older implementationsflagTrueTrueflagvalues : true or false or on or off
Example : true
40nis-domainSpecifies the NIS domain (entered as an ASCII character string) for the client.quoted_stringTrueTruetextExample : domain.com
41nis-serversSpecifies a list of IP addresses for NIS servers available to the client. Servers are listed in order of preference.ipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
42ntp-serversSpecifies a list of IP addresses for NTP servers available to the client. Servers are listed in order of preference.ipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
43vendor-encapsulated-optionsSpecifies vendor-specific information. This allows clients and servers to exchange vendor-specific information. The vendor is specified in the Vendor Class Identifier option (option 60).quoted_stringTrueTruestringExample : string_value
44netbios-name-serversSpecifies a list of NetBIOS Name Servers (NBNS) aka (WINS servers) (RFC 1001 and RFC 1002). NBNS servers are listed in order of preference.ipv4addressTrueTrueip-addressType : ipv4
Example : 1.1.1.1
45netbios-dd-serverSpecifies a list of NetBIOS Datagram Distribution Servers (NBDD) addresses (RFC 1001 and RFC 1002). NBDD server addresses are listed in order of preference.ipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
46netbios-node-typeSpecifies the client as a specific NETBIOS Node Typeuint8TrueTrueuint8Range : 0-255
Example : 1
47netbios-scopeSpecifies the NetBIOS over TCP/IP scope parameter (RFC 1001 and RFC 1002) for the client. While the DHCP server itself may not have a specific option for NetBIOS scope, it can be configured to provide NetBIOS settings to DHCP clients through DHCP options.
DHCP Option 44 (WINS/NBT Servers) and DHCP Option 46 (WINS/NBT Node Type) are examples of DHCP options that can be used to provide NetBIOS-related information to clients.		quoted_stringTrueTruestringExample : string_value
48font-serversSpecifies a list of IP addresses of X Window System Font servers available to the client. X Window System Font servers are listed in order of preference.ipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
49x-display-managerX Window System display manager addresses, such as those associated with XDMCP (X Display Manager Control Protocol), are typically configured separately from DHCP. The XDMCP addresses are commonly set in the configuration of the X display manager on the client or server.

If you are looking to configure XDMCP addresses for X Window System display managers, you would typically do so through the configuration files specific to the X display manager software you are using (e.g., LightDM, GDM, XDM, etc.). The configuration files might include settings for specifying XDMCP servers, display addresses, and related parameters.		ipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
50dhcp-requested-addressIP address requested by the client (within a Discover message).When a DHCP client is in the initial stages of obtaining an IP address, it sends a DHCP Discover message to the network, indicating that it is seeking an available IP address. In this Discover message, the client may include DHCP Option 50 to express its preference or specific request for a particular IP address.ipv4addressTrueTrueip-addressType : ipv4
Example : 1.1.1.1
51dhcp-lease-timeIP address lease time requested by the client (within a Discover or Request message).This option is used in a client request (DHCPDISCOVER or DHCPREQUEST) to allow the client to request a lease time for the IP address. In a server reply (DHCPOFFER), a DHCP server uses this option to specify the lease time it is willing to offer.uint32TrueTrueuint32Range : 0-4,294,967,295
Example : 12345
52dhcp-option-overloadIndicates that the sname and/or file DHCP header fields contain additional DHCP option information if options to return to the client exceed the normal option space in the messageuint8TrueTrueuint8Range : 0-255
Example : 1
53dhcp-message-typeDHCP message type option is used to convey the type of DHCP message being sent between the DHCP client and server. This option is essential for both the initiation and acknowledgment of DHCP messages, helping devices understand the purpose of the received DHCP packet.

The DHCP message type option is specified by Option 53 in the DHCP protocol. The values associated with this option indicate different DHCP message types. Here are some common DHCP message types and their corresponding values:

DHCPDISCOVER (Client to Server) - Value: 1:

The DHCPDISCOVER message is sent by a DHCP client to discover available DHCP servers on the network.
DHCPOFFER (Server to Client) - Value: 2:

The DHCPOFFER message is sent by a DHCP server in response to a DHCPDISCOVER message. It offers configuration parameters, including IP address lease information, to the client.
DHCPREQUEST (Client to Server) - Value: 3:

The DHCPREQUEST message is sent by a DHCP client to formally request the offered configuration parameters from a specific DHCP server.
DHCPACK (Server to Client) - Value: 5:

The DHCPACK message is sent by the DHCP server to acknowledge the DHCPREQUEST from the client and confirm the lease of the offered configuration parameters.
DHCPNAK (Server to Client) - Value: 6:

The DHCPNAK message is sent by the DHCP server to indicate that the requested configuration parameters in the DHCPREQUEST are not available, and the client needs to restart the configuration process.
DHCPRELEASE (Client to Server) - Value: 7:

The DHCPRELEASE message is sent by a DHCP client to inform the server that it is releasing its IP address lease and will no longer use it.
These values are included in the DHCP message type option (Option 53) as part of the DHCP packet. The DHCP client and server use these values to understand the purpose of the received DHCP message and respond accordingly during the dynamic IP address allocation process.		uint8TrueTrueuint8Range : 0-255
Example : 1
54dhcp-server-identifierDHCP server identification provided in the Offer (and Request and optionally ACK, NAK) to identify the server, e.g. to distinguish among multiple offersipv4addressTrueTrueip-addressType : ipv4
Example : 1.1.1.1
55dhcp-parameter-request-listList of DHCP option code numbers for parameters requested by the clientuint8TrueTrueuint8 [, uint8... ]Range : 0-255
Example : 123,153,..,etc
56dhcp-messageText containing an error message; can be used by the server in a Nak message to the client or by the client in a Decline message; e.g. this text could be included in logging detailsquoted_stringTrueTruetextExample : message
57dhcp-max-message-sizeThe maximum DHCP message length the client is willing to acceptuint16TrueTrueuint16Range : 0-65535
Example : 1024
58dhcp-renewal-timeInterval from address assignment time to the time the client enters the Renewing stateuint32TrueTrueuint32Range : 0-4,294,967,295
Example : 12345
59dhcp-rebinding-timeInterval from address assignment time to the time the client enters the Rebinding state.uint32TrueTrueuint32Range : 0-4,294,967,295
Example : 12345
60vendor-class-identifier—quoted_stringTrueTruestringExample : string_value
61dhcp-client-identifierClient identifier used by DHCP clients to uniquely identify themselves to the DHCP server during the DHCP negotiation process. The client identifier is typically associated with a specific hardware address or other unique identifier for the client device. Example: option dhcp-client-identifier 01:02:03:04:05:06; In this example:

01 indicates that the subsequent bytes represent the client's hardware address.
02:03:04:05:06 is the actual hardware address (MAC address) of the DHCP client.		quoted_stringTrueTruestringExample : value
62nwip-domainNetware/IP Domain Namequoted_stringTrueTruestringExample : domain.com
63nwip-suboptionsNetware/IP sub Optionsquoted_stringTrueTruestringExample : string_data
64nisplus-domainNetwork Information Services+ (NIS+) client domain namequoted_stringTrueTruetextExample : domain.com
65nisplus-serversNetwork Information Services+ (NIS+) server addressesipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
66tftp-server-nameTFTP server name can be used when the sname DHCP header field has been overloaded with other options. When a DHCP client receives Option 66 as part of its DHCP configuration, it uses the provided information to locate and connect to a TFTP server. This is particularly useful in scenarios where network devices need to retrieve configuration files or firmware updates during the initialization process.quoted_stringTrueTruetextExample : text_server_name
67bootfile-nameBoot file name; can be used when the file DHCP header field has been overloaded with other optionsquoted_stringTrueTrue—Example : string_filename
68mobile-ip-home-agentMobile IP home agent addressesipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
69smtp-serverSimple Mail Transfer Protocol (SMTP) server addresses for outgoing e-mail.ipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
70pop-serverPost Office Protocol v3 (POP3) server addresses for incoming e-mail retrieval.ipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
71nntp-serverNetwork News Transport Protocol (NNTP) server addresses.ipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
72www-serverThe WWW server option specifies a list of WWW servers available to the client. Servers should be listed in order of preference.ipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
73finger-serverFinger server addresses; finger servers enable retrieval of host user information regarding login name, login duration, and moreipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
74irc-serverInternet Relay Chat (IRC) server addressesipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
75streettalk-serverStreetTalk server addresses; StreetTalk was a Banyan Vines user and resource directoryipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
76streettalk-directory-assistance-serverStreetTalk Directory Assistance (STDA) server addresses; StreetTalk was a Banyan Vines user and resource directoryipv4addressTrueTrueip-addressType : ipv4
Example : 1.1.1.1
77user-classUser Class Identifierquoted_stringTrueTruestringExample : string_value
78slp-directory-agentService Location Protocol (SLP) Directory Agent IP address(es)stringTrueTrueboolean ip-address [, ip-address... ]values : true or false or on or off , Type : ipv4
Example : true 1.1.1.1,2.2.2.2,..,etc
79slp-service-scopeService Location Protocol (SLP) service scope the SLP agent is configured
to use.		stringTrueTrueboolean textvalues : true or false or on or off
Example : true "text_value"
80rapid-commit[Not supported] Rapid Commit - requests a two-packet DHCP transaction instead of the normal four packet DORA process for mobility or overhead-constrained applications—False———
81fqdnConveys the client's fully qualified domain name to the DHCP server. This option helps in associating a specific FQDN with a DHCP client, providing a human-readable identifier for the client.

The DHCP option 81 is structured as follows:

Code: 81
Length: Length of the FQDN field
Flags: Flags indicating the format of the FQDN
RCODE1: Return code for the server's use
RCODE2: Return code for the client's use
Fully Qualified Domain Name: The actual FQDN of the client
Here is an example of a DHCP option 81:

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Option: (t=81,l=15) domain-search "example.com". This option is useful in scenarios where clients need to be identified and associated with specific FQDNs within the network. The server can use this information for various purposes, including updating DNS records or maintaining a more human-readable record of leased addresses.		quoted_stringTrueTrue—Type : fqdn
82relay-agent-informationRelay Agent Information - additional client information supplied by the intervening relay agentstringTrueTrue—Example : "string_value"
83iSNS [Internet Storage Name Service]Internet Storage Name Service (ISNS) server addresses and iSNS application information—————
84UnassignedThese options are supported if the option value type is IP, ASCII, or HEX—————
85nds-serversNovell Directory Services (NDS) Server IP addresses to contact for NDS client authentication and access the NDS directory repositoryipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
86nds-tree-nameNovell Directory Services (NDS) tree name of the NDS repository the client should contactquoted_stringTrueTrue—Example : string_name
87nds-contextNovell Directory Services (NDS) initial context within the NDS repository the NDS client should usequoted_stringTrueTrue—Example : string_value
88bcms-controller-namesBroadcast and Multicast Server domain name (FQDN) list, used to construct follow-up SRV query(ies) (BCMCS is used in 3G wireless networks to enable mobiles to receive broadcast and multicast services)quoted_stringTrueTruedomain-listExample : example.com,domainexample.com,..,etc
89bcms-controller-address [BCMCS Controller IPv4 Address Option]Broadcast and Multicast Server (BCMCS) Controller IP address(es) (BCMCS is used in 3G wireless networks to enable mobiles to receive broadcast and multicast services)ipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
90authenticationAuthentication option used to communicate authentication information between the client and server in accordance with the DHCP authentication protocolquoted_stringFalseTrue——
91client-last-transaction-timeSeconds since the last DHCP transaction with the client on this lease as queried in a DHCP Lease Query messageuint32TrueTrueuint32Range : 0-4,294,967,295
Example : 12345
92associated-ipList of IP addresses associated with the client as queried in a DHCP Lease Query messageipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
93pxe-system-typePXE client system architecture type(s) each encoded as 16-bit code, e.g. Intel x86PC, DEC Alpha, EFI x86-64, etc.uint16TrueTrueuint16 [, uint6... ]Range : 0-65535
Example : 1024,1024,..,etc
94pxe-interface-idPXE client network interface identifier with individual octets encoded for interface type, interface major version number, and interface minor version numberuint8TrueTrueuint8 uint8 uint8Range : 0-255
Example : 1 2 3
95LDAPLightweight Directory Access Protocol servers; this option is used by Apple Computer though no governing RFC has been published—FalseTrue——
96Unassigned——————
97pxe-client-idPXE client machine identifier with encoded type and identifier valuestringTrueTrueuint8 stringRange : 0-255 and string
Example : 1 "string_value"
98uap-serversList of locations (URLs) for services capable of processing authentication requests encapsulated using Open Group's User Authentication Protocol (UAP)quoted_stringTrueTruetextExample : text_value
99geoconf-civicLocation of the server, network element closest to the client or the client itself as provided by the server encoded in country-specific civic (e.g. postal) formatquoted_stringTrueTruestringExample : string_value
100pcodeTime Zone encoded as IEEE 1003.1 TZ (POSIX)quoted_stringTrueTruetextExample : text_value
101tcodeReference to a local (on the client) TZ database for lookup of time zonequoted_stringTrueTruetextExample : text_value
102-111UnassignedThese options are supported if the option value type is IP, ASCII, or HEX—————
108v6-only-preferredspecifies a method to use a DHCP option (delivered over IPv4) to disable the IPv4 protocol on a host (resulting in it being IPv6-only). DHCP Option 108 contains a 32-bit unsigned integer that represents the number of seconds the client should disable DHCPv4. Following are the timers that are defined in the RFC:

V6ONLY_WAIT (default = 1800 seconds, 30 min)
MIN_V6ONLY_WAIT (default = 300 seconds, 5 min), you can select assign the timer more value like 3600 seconds or more depending on your requirements.		uint32TrueTrueuint32Range : 0-4,294,967,295
Example : 12345
109softwire-addressIPv6 address assigned via DHCPv4 over DHCPv6—————
110-111Unassigned——————
112netinfo-server-addressNetInfo Parent Server Address; this option is used by Apple Computer though no governing RFC has been published; NetInfo is a distributed database user and resource information for Apple devices.ipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
113netinfo-server-tagNetInfo Parent Server Tag; this option is used by Apple Computer though no governing RFC has been published. NetInfo is distributed database user and resource information for Apple devices.quoted_stringTrueTruetextExample : text_value
114dhcp-captive-portalInforms the client that they are behind a captive portal with a URI to an authentication functionquoted_stringTrueTruestringhttp://www.YourDomain.com.
115UnassignedThese options are supported if the option value type is IP, ASCII, or HEX—————
116auto-configInstructs the client to auto-configure a link local address (69.254.0.0/16) or not. This can be used by the DHCP server to inform the client that it has no IP addresses to assign and that the client may or may not auto-configureuint8TrueTrueuint8Range : 0-255
Example : 1
117name-service-searchLists one or more name services in priority order that the client should use for name resolution: DNS, NIS, NIS+, or WINSuint16TrueTrueuint16 [, uint6... ]Range : 0-65535
Example : 1024,1024,..,etc
118subnet-selectionIdentifies an IP subnet (address) from which to allocate an IP address to this client - overrides the GIAddr setting or DHCP server interface on which a broadcast Discover was receivedipv4addressTrueTrueip-addressType : ipv4
Example : 1.1.1.1
119domain-searchList of one or more domains for configuration of the client's resolver. If the application requests a resolution for a non-FQDN hostname, these domain(s) will successively be appended to the hostname prior to queryingquoted_stringTrueTruedomain-listExample : example.com,sales.example.com,eng.example.com,..,etc
123Location Configuration informationProvides the client its Location Configuration Information (LCI), including latitude, longitude, altitude and resolution of each coordinate—————
124vivco [Vendor-Identifying Vendor Class]Enables specification of multiple vendor classes, each identified by IANA-assigned Enterprise Number (EN); this is useful to identify the hardware vendor, software vendor, application vendor, etc. supporting the devicequoted_stringTrueTruestringExample : string_value
125vivso [Vendor-Identifying Vendor-Specific Information]Set of DHCP options grouped by vendor as identified by IANA-assigned Enterprise Number (EN);quoted_stringTrueTruestringExample : string_value
126-127UnassignedThese options are supported if the option value type is IP, ASCII, or HEX—————
128-135PXE - Udefined [Vendor Specific]These options are supported if the option value type is IP, ASCII, or HEX—————
136pana-agentIdentifies one or more IPv4 addresses of PANA (Protocol for carrying Authentication for Network Access) Authentication Agents for use by the client for authentication and authorization for network access service.ipv4addressTrueTrueip-addressType : ipv4
Example : 1.1.1.1
137v4-lostLocation to Service Translation (LOST) server domain name; LOST protocol maps service identifiers and location information to service URLSquoted_stringFalseTruedomain-nameExample : domainname.com
138capwap-ac-v4Control and Provisioning of Wireless Access Points (CAPWAP) Access Controller IP address(es) to which the client may connectipv4addressTrueTrueip-addressType : ipv4
Example : 1.1.1.1
139IPv4 Address MOSIPv4 address(es) for servers providing particular types of IEEE 802.21 Mobility Service (MOS)—————
140MOS Service FQDNSFQDN(s) for servers providing particular types of IEEE 802.21 Mobility Service (MOS)—————
141sip-ua-cs-domains [SIP UA Configuration Service Domains]DHCP SIP user agent configuration service domainsquoted_stringFalseTrue——
142ipv4-address-andsfSpecifies the IP addresses of the Access Network Discovery and Selection Function (ANDSF) servers. available to the client. The servers are listed in order of priority.ipv4addressTrueTrueip-addressType : ipv4
Example : 1.1.1.1
143SZTP bootstrap server URIsSecure Zero Touch Provisioning (SZTP) bootstrap server list—————
144GoSpatial LocationGeographic location (latitude, longitude and altitude) of the client as provided by the DHCP server—————
145Force Renew Nonce CapableNonce value sent from the server to the client for authentication of possible future ForceRenew messages—————
146rdnss-selectionRecursive DNS Server selection for multi-interfaced nodes. This option is supported if the option value type is IP, ASCII, or HEXstringTrueTrueuint8 ip-address ip-address domain-nameRange : 0-255 , Type : ipv4
Example : 5 1.1.1.1 2.2.2.2 "domainName.com"
147-149UnassignedThese options are supported if the option value type is IP, ASCII, or HEX—————
150tftp-server-addressSpecific to VoIP (Voice over Internet Protocol) environments, and it is used to provide the IP address or hostname of a TFTP (Trivial File Transfer Protocol) server to VoIP phones or devices during the DHCP lease negotiation process. TFTP is commonly employed in VoIP deployments to download configuration files or firmware updates required for the proper functioning of VoIP devices. The option contains the IP address or hostname of the TFTP server, allowing the VoIP device to establish a connection to the specified server and retrieve its configuration files.ipv4addressTrueTrueip-address [, ip-address... ]Type : ipv4
Example : 1.1.1.1,2.2.2.2,..,etc
151DHCP Bulk Lease Query- status codeNot supported—————
152DHCP Bulk Lease Query- base timeDHCP Bulk LeaseQuery base-time at which the LeaseQuery was created—————
153DHCP Bulk Lease Query- start time of stateDHCP Bulk LeaseQuery elapsed time since the given IP address entered its current state—————
154DHCP Bulk Lease Query- query start timeDHCP Bulk LeaseQuery filters results by the time after which lease binding changes are requested—————
155DHCP Bulk Lease Query- query end timeDHCP Bulk LeaseQuery filters results by the time before which lease binding changes are requested—————
156DHCP Bulk Lease Query- dhcp stateDHCP Bulk LeaseQuery dhcp lease state. This option is supported if the option value type is IP, ASCII, or HEX—————
157DHCP Bulk Lease Query- data sourceDHCP Bulk LeaseQuery data source when two or more servers have information about the IP address binding—————
158DCHPv4 PCP ServerPort Control Protocol(PCP) server IP address(es).—————
159v4-portparams [DHCPv4 Port Parameters]Shared IPv4 address space port parametersquoted_stringFalseTrue——
160v4-captive-portalThe contact URI for the captive portal that the user should connect to. This option is supported if the option value type is IP, ASCII, or HEXquoted_stringFalseTrue——
161-174UnassignedThese options are supported if the option value type is IP, ASCII, or HEX—————
175EtherbootThese options are supported if the option value type is IP, ASCII, or HEX—————
176IP Telephone-Voice-ServerConfigures the IP telephone voice parameters for Avaya IP phones running as DHCP clients.—————
177Etherboot[Pkt Cable- Cable Home]This option is supported if the option value type is IP, ASCII, or HEX—————
178-207UnassignedThese options are supported if theoption value type is IP, ASCII, or HEX—————
209PXE Configuration FileSpecifies the configuration filename or file pathname to be used in a PXELINUX environment. for second stage PXE boot loading.—————
210PXE Path PrefixSpecifies a path prefix for the configuration file used in a PXELINUX environment, as specified in the PXE configuration file option [204]—————
211PXE Reboot TimeNumber of seconds to wait to reboot if TFTP server is unreachable—————
212option-6rdService provider's 6rd prefix and 6rd border relay IPv4 address(es)stringTrueTrueuint8 uint8 ip6-address ip-address [, ip-address ...]uint8 Range : 0-255, Address Type : ipv6 and ipv4
Example : 1 2 2001:db8:3333:4444:5555:6666:7777:8888 1.1.1.1,2.2.2.2,..,etc
213v4-access-domainLocal Location Information Server (LIS) discovery.Specifies the access network domain name available to the client for the purposes of discovering a Local Information Server (LIS).quoted_stringFalseTruedomain-nameExample : domainname.com
214-219UnassignedThese options are supported if theoption value type is IP, ASCII, or HEX—————
220Subnet allocation option (Tentatively assigned)This options is supported if the option value type is IP, ASCII, or HEX—————
221Virtual subnet selection option (Tentatively assigned)This option is supported if the option value type is IP, ASCII, or HEX—————
222-223UnassignedThese options are supported if the option value type is IP, ASCII, or HEX—————
224-241Reserved (Private Use)These options are supported if the option value type is IP, ASCII, or HEX—————
242IP Tele-DataSrvrConfigures the IP telephone data parameters for Avaya IP phones running as DHCP clients.—————
243-251Reserved (Private Use)These options are supported if the option value type is IP, ASCII, or HEX—————
252WPADConfigures the Proxy-Auto Config (PAC) file location string for the Web Proxy Auto-Discovery (WPAD) supported DHCP clients.—————
253-254Reserved (Private Use)These options are supported if the option value type is P, ASCII, or HEX—————
255End (None)——————

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