DNS & DHCP

Printer-friendly versionPrinter-friendly version

Network Services provides DNS and DHCP services for all schools, programs, and departments in 4J. In addition 4J Network Services is the primary DNS for lane.edu. If you need to register a device with the district's DNS and DHCP servers, then please fill out the form at the Network Address Request page.

DNS

DNS (Domain Name Service) is the network service that maps internet names to IP addresses. There are two domains- .lane.edu and .intra.lane.edu. Names in the .lane.edu domain are resolvable by Internet nameservers. Names in the .intra.lane.edu are not resolvable by Internet nameservers. This is useful for hosts on private address spaces within 4JNet (not reachable from the Internet).

If a node has multiple IP addresses, DNS will return all IP addresses in random order. If the DNS request comes from the same network as one of the IP addresses, that address will be returned first in the list. For reverse lookup, the name closest to the address will be returned first. In other words, the order is IP address name, interface name, node name. In the case of multiple node names, names are returned in random order.

DDNS

DDNS (Dynamic DNS) is the network service that provides the capability for a networked host to register its name with a domain name server. At 4J DDNS is used with Windows client computers to register the clients with their Microsoft domain and to resolve Window server addresses for these clients.

DHCP

The DHCP (Dynamic Host Configuration Protocol) and BootP (Bootstrap Protocol) pass network configuration information to a host during startup. DHCP is configured on a unique hardware address. DHCP is also described in Internet RFCs 2131 and 2132. Note that BOOTP is a subset of DHCP commands.

Default Node DHCP options

The default Node DHCP options at 4J are IP address, subnet mask, gateway, domain name and domain name servers. The option numbers come from RFCs 2131 and 2132.

DHCP Option Option Number Description
IP Address 50 returns IP address assigned to requesting hardware address
Subnet mask 1 returns 255.255.255.0, in general
Gateway 3 for 158.165.x addresses, returns 158.165.x.1; for 171.65.x addresses, returns 158.165.x.1
Domain name 15 returns domain name asssigned to the Node
Domain name servers 6 158.165.1.26 and 158.165.1.20 are returned

Additional DHCP options

The following additional DHCP options may be set for Node interfaces, Networks, or address spaces.

DHCP Option Option Number Node Interface Net Address Space Description
next-server   Y Y Y boot/config server
tftp-server-name 66 Y Y Y TFTP boot/config server
filename 67 Y N Y boot/config file - e.g. thin clients
log-servers 7 Y Y Y  
domain-name 15 Y Y Y e.g., lane.edu
domain-name-servers 5 Y Y Y DNS servers
netbios-name-servers 44 Y Y Y WINS servers
netbios-node-type 46 Y Y Y 1=B, 2=P, 4=M, 8=H
max-lease-time   Y Y Y  
default-lease-time 51 Y Y Y DHCP lease time (currently 8 hours)