User Manual

DHCP Configuration Examples
134 Enterasys X-Pedition User Reference Manual
10. Specify a database update interval of every 15 minutes.
Configuring Secondary Subnets
In some network environments, multiple logical subnets can be imposed on a single physical
segment. These logical subnets are sometimes referred to as “secondary subnets” or “secondary
networks.” For these environments, the DHCP server may need to give out addresses on different
subnets. The DNS server, DNS domain, and WINS server may be the same for clients on different
secondary subnets, however, the default gateway will most likely be different since it must be a
router on the client’s local subnet.
The following example shows a simple configuration to support secondary subnets 10.1.x.x and
10.2.x.x.
1. Define the network parameters for ‘scope1’ with the default gateway 10.1.1.1.
2. Define the address pool for ‘scope1’.
3. Define the network parameters for ‘scope2’ with the default gateway 10.2.1.1.
4. Define the address pool for ‘scope2’.
5. Create a superscope ‘super1’ that includes ‘scope1’.
6. Include ‘scope2’ in the superscope ‘super1’.
Since there are multiple pools of IP addresses, the pool associated with ‘scope1’ is used first since
‘scope1’ is applied to the interface before ‘scope2’. Clients that are given an address from ‘scope1’
will also be given parameters from ‘scope1,’ which includes the default gateway 10.1.1.1 that
dhcp global set commit-interval 15
dhcp scope1 define parameters address-netmask 10.1.0.0/16 gateway 10.1.1.1 dns-domain
acme.com dns-server 10.1.44.55
dhcp scope1 define pool 10.1.1.10-10.1.1.20
dhcp scope2 define parameters address-netmask 10.2.0.0/16 gateway 10.2.1.1 dns-domain
acme.com dns-server 10.1.77.88
dhcp scope2 define pool 10.2.1.40-10.2.1.50
dhcp scope1 attach superscope super1
dhcp scope2 attach superscope super1