Users Guide
Automatic address allocation
Automatic address allocation is an address assignment method that the DHCP server uses to lease an IP address to a client from
a pool of available addresses. You cannot configure an empty DHCP pool under a DHCP pool configuration. For a successful
commit, you must have either a network statement or host/hardware-address (manual binding) configuration. An IP address
pool is a range of addresses that the DHCP server assigns. Both IPv4 and IPv6 DHCP pool configuration is supported. The
subnet number indexes the address pools.
1. Enable the DHCP server in CONFIGURATION mode.
ip dhcp server
2. Create an IP address pool and provide a name in DHCP mode.
pool name
3. Enter the subnet from which the DHCP server may assign addresses in DHCP POOL mode. The network option specifies
the subnet address. The prefix-length option specifies the number of bits used for the network portion of the address;
for IPv4 addresses, the valid values are from 17 to 30.
network network/prefix-length
4. Enter a range of IP addresses from the subnet specified above, which the DHCP server uses to assign addresses in DHCP
<POOL> mode.
range {ip-address1 [ip-address2]}
NOTE:
Configure at least one interface to match one of the configured network pools. An interface matches a network
pool when its IP address is included in the subnet defined for that network pool. For example, an interface with IP
address 10.1.1.1/24 matches a pool configured with network 10.1.1.0/24.
DHCP server automatic address allocation
OS10(config)# ip dhcp server
OS10(config-dhcp)# pool Dell
OS10(config-dhcp-Dell)# default-router 20.1.1.1
OS10(config-dhcp-Dell)# network 20.1.1.0/24
OS10(config-dhcp-Dell)# range 20.1.1.2 20.1.1.8
Show running configuration
OS10(conf-dhcp-Dell)# do show running-configuration
...
!
ip dhcp server
!
pool Dell
network 20.1.1.0/24
default-router 20.1.1.1
range 20.1.1.2 20.1.1.8
Address lease time
Use the lease {days [hours] [minutes] | infinite} command to configure an address lease time. The default is
24 hours.
OS10(config)# ip dhcp server
OS10(conf-dhcp)# pool Dell
OS10(conf-dhcp-Dell)# lease 36
Default gateway
Ensure the IP address of the default router is on the same subnet as the client.
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System management