Appendix B – DHCPv6 options
A DHCP server can provide optional configuration settings to clients. Sophos Firewall supports the following DHCP options.
To set the options, see DHCP.
Note
Some table content may not be visible. Use the horizontal scroll bar at the bottom of the table, or click and drag horizontally, to see the remaining content.
| Option number | Name | Description | Data type | Data format | Data value (example) | RFC |
|---|---|---|---|---|---|---|
| 7 | Preference | Server preference value (0-255, higher is preferred) | One-byte numeric value | One-byte numeric value | 255 | RFC 8415 |
| 12 | Unicast | Server unicast address for client communication | IP addresses | ipv6-address | "2001:db8::1" | RFC 8415 |
| 21 | SIP-Servers-Names | Domain names of SIP outbound proxy servers | String | array of | "sip.example.org,sip2.example.org" | RFC 3319 |
| 22 | SIP-Servers-Addresses | IPv6 addresses of SIP outbound proxy servers | Array of IP addresses | array of | "2001:db8::21,2001:db8::22" | RFC 3319 |
| 23 | Name-Servers | IPv6 addresses of DNS recursive name servers | Array of IP addresses | array of | "2001:db8::53,2001:db8::54" | RFC 3646 |
| 24 | Domain-Search | Domain search list for hostname resolution | String | array of | "example.com,eng.example.org" | RFC 3646 |
| 27 | NIS-Servers | IPv6 addresses of NIS servers | Array of IP addresses | array of | "2001:db8::27,2001:db8::28" | RFC 3898 |
| 28 | NISP-Servers | IPv6 addresses of NIS+ servers | Array of IP addresses | array of | "2001:db8::29,2001:db8::30" | RFC 3898 |
| 29 | NIS-Domain-Name | NIS domain name for the client | String | array of | "nis.example.org" | RFC 3898 |
| 30 | NISP-Domain-Name | NIS+ domain name for the client | String | array of | "nisplus.example.org" | RFC 3898 |
| 31 | SNTP-Servers | IPv6 addresses of SNTP time servers | Array of IP addresses | array of | "2001:db8::31,2001:db8::32" | RFC 4075 |
| 32 | INFO-Refresh-Time | Upper bound in seconds for DHCPv6 info refresh | Four-byte numeric value | Four-byte numeric value | 86400 | RFC 8415 |
| 33 | BCMS-Server-D | BCMS controller domain names | String | array of | "bcmcs.example.org" | RFC 4280 |
| 34 | BCMS-Server-A | BCMS controller IPv6 addresses | Array of IP addresses | array of | "2001:db8::33,2001:db8::34" | RFC 4280 |
| 36 | GeoConf_Civic | Civic address location information | String | One-byte numeric value, Two-byte numeric value, Array of Hex format data | "0,0x5553,15 9D,A3 FF" | RFC 4776 |
| 37 | Remote_Id | Remote identifier for relay agent | String | Four-byte numeric value, Hex format data | "4294967295,1A BB AD AB BA D0 00 00 00 00 00 00 00 00 CA FE" | RFC 4649 |
| 38 | Subscriber_Id | Subscriber identifier for relay agent | String | Hex format data | "A3 FF" | RFC 4580 |
| 39 | Client_FQDN | Client's fully qualified domain name | String | One-byte numeric value, fqdn | "224,client.example.org" | RFC 4704 |
| 40 | Pana_Agent | PANA agent IPv6 addresses | Array of IP addresses | array of | "2001:db8::40" | RFC 5192 |
| 41 | New_Posix_Timezone | POSIX timezone string (IEEE 1003.1) | String | String | "EST5EDT,M3.2.0,M11.1.0" | RFC 4833 |
| 42 | New_Tzdb_Timezone | IANA timezone database name | String | String | "America/New_York" | RFC 4833 |
| 43 | ERO | Option codes server should echo back | Array of two-byte numeric values | Array of two-byte numeric values | "16,32,42" | RFC 4994 |
| 44 | LQ_Query_1 | Leasequery query option (query type + address) | String | One-byte numeric value, IPv6 address | "1,2001:db8::100" | RFC 5007 |
| 46 | Clt_Time_1 | Leasequery client last transaction time | Four-byte numeric value | Four-byte numeric value | 3600 | RFC 5007 |
| 47 | LQ_Relay_Data_1 | Leasequery relay data (address + message) | String | IPv6 address, Hex format data | "2001:db8::18,1A BB AD AB BA D0 00 00 00 00 00 00 00 00 CA FE" | RFC 5007 |
| 48 | LQ_Client_Link_1 | Leasequery client link addresses | Array of IP addresses | array of | "2001:db8::1,2001:db8::2" | RFC 5007 |
| 51 | V6_Lost | LoST (Location-to-Service Translation) server FQDN | String | fqdn | "lost.example.org" | RFC 5223 |
| 52 | Capwap_AC_V6 | CAPWAP Access Controller IPv6 addresses | Array of IP addresses | array of | "2001:db8::52,2001:db8::53" | RFC 5417 |
| 53 | Relay_Id | Unique relay agent identifier | String | Hex format data | "1A BB AD AB BA D0 00 00 00 00 00 00 00 00 CA FE" | RFC 5460 |
| 57 | V6_Access_Domain | Access network domain name | String | fqdn | "access.example.org" | RFC 5986 |
| 58 | SIP_UA_CS_List | SIP UA CS domains list | String | array of | "sipcs.example.org" | RFC 6011 |
| 59 | Bootfile_URL | URL for network boot file | String | String | "tftp://[2001:db8::1]/bootfile.efi" | RFC 5970 |
| 60 | Bootfile_Param | Boot file parameters list | String | array of | "root=/dev/sda2,quiet,splash" | RFC 5970 |
| 61 | Client_Arch_Type | Client system architecture (UEFI/BIOS) | Array of two-byte numeric values | Array of two-byte numeric values | "1,3,5,7" | RFC 5970 |
| 62 | NII | Network interface type and version | String | One-byte numeric value, Array of one-byte numeric values, One-byte numeric value | "1,2,11,13" | RFC 5970 |
| 64 | AFTR_Name | DS-Lite AFTR tunnel endpoint FQDN | String | fqdn | "aftr.example.org" | RFC 6334 |
| 65 | ERP_Local_Domain_Name | EAP Re-auth Protocol local domain name | String | fqdn | "erp.example.org" | RFC 6440 |
| 67 | PD_Exclude | Prefix to exclude from delegated prefix | String | Hex format data | "2001:db8:1:1::/64" | RFC 6603 |
| 74 | RDNSS_Selection | Recursive DNS server selection info | String | IPv6 address, uint8, array of | "2001:db8::23,1,example.com,example.org" | RFC 6731 |
| 79 | Client_LinkLayer_Addr | Client hardware address (from relay) | String | Hex format data | "1A BB AD AB BA D0 00 00 00 00 00 00 00 00 CA FE" | RFC 6939 |
| 80 | Link_Address | Link address for leasequery | IP addresses | ipv6-address | "2001:db8::1" | RFC 6977 |
| 82 | SolMax_RT | Maximum Solicit timeout value in seconds | Four-byte numeric value | Four-byte numeric value | 3600 | RFC 8415 |
| 83 | Inf_Max_RT | Maximum Information-Request timeout in seconds | Four-byte numeric value | Four-byte numeric value | 86400 | RFC 8415 |
| 88 | DHCPv6_Server_Addr | DHCPv4-over-DHCPv6 server addresses | Array of IP addresses | array of | "2001:db8::88,2001:db8::89" | RFC 7341 |
| 103 | V6_Captive_Portal | URL for captive portal detection | String | String | "https://portal.example.org/captive" | RFC 8910 |
| 136 | V6_SZTP_Redirect | Secure Zero Touch Provisioning redirect URLs | String | array of | "https://sztp1.example.com:8443,https://sztp2.example.com:8444" | RFC 8572 |
| 143 | IPv6_Address_ANDSF | Access Network Discovery server addresses | Array of IP addresses | array of | "2001:db8::143" | RFC 6153 |
| Custom | Custom | Create a custom DHCP option. Specify the option code, select the option type, and enter the option value. | User-defined | Depends on the selected type | User-defined | N/A |