Dell MX5108n OS10 Enterprise Edition User Guide for PowerEdge MX IO Modules Re - Page 449

Automatic address allocation, Address lease time, Default gateway

Page 449 highlights

DHCP automates network-parameter assignment to network devices. Even in small networks, DHCP makes it easier to add new devices to the network. The DHCP access service provides a centralized, server-based setup to add clients to the network. This setup means you do not have to manually create and maintain IP address assignments for clients. When you use DHCP to manage a pool or IP addresses among hosts, you reduce the number of IP addresses you need. DHCP manages the IP address pool by leasing an IP address to a host for a limited period, allowing the DHCP server to share a limited number of IP addresses. DHCP also provides a central database of devices that connects to the network and eliminates duplicate resource assignments. 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. The subnet number indexes the address pools. 1 Enable DHCP server-assigned dynamic addresses on an interface in DHCP mode. ip dhcp server 2 Create an IP address pool and provide a name in DHCP mode. pool name 3 Enter the range of IP addresses from which the DHCP server may assign addresses in DHCP 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 (18 to 31). network network/prefix-length DHCP server automatic address allocation OS10(config)# ip dhcp server OS10(conf-dhcp)# pool Dell OS10(conf-dhcp-Dell)# network 20.1.1.0/24 Show running configuration OS10(conf-dhcp-Dell)# do show running-configuration ... ! ip dhcp server ! pool Dell lease 24 network 20.1.1.0/24 default-router 20.1.1.1 Address lease time Use the lease {days [hours] [minutes] | infinite} command to configure an address lease time (default 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. 1 Enable DHCP server-assigned dynamic addresses on an interface in CONFIGURATION mode. ip dhcp server System management 449

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DHCP automates network-parameter assignment to network devices. Even in small networks, DHCP makes it easier to add new devices to
the network. The DHCP access service provides a centralized, server-based setup to add clients to the network. This setup means you do
not have to manually create and maintain IP address assignments for clients.
When you use DHCP to manage a pool or IP addresses among hosts, you reduce the number of IP addresses you need. DHCP manages
the IP address pool by leasing an IP address to a host for a limited period, allowing the DHCP server to share a limited number of IP
addresses. DHCP also provides a central database of devices that connects to the network and eliminates duplicate resource assignments.
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. The subnet number indexes the address pools.
1
Enable DHCP server-assigned dynamic addresses on an interface in DHCP <
POOL
> mode.
ip dhcp server
2
Create an IP address pool and provide a name in DHCP mode.
pool
name
3
Enter the range of IP addresses 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
(18 to 31).
network
network/prefix-length
DHCP server automatic address allocation
OS10(config)# ip dhcp server
OS10(conf-dhcp)# pool Dell
OS10(conf-dhcp-Dell)# network 20.1.1.0/24
Show running
configuration
OS10(conf-dhcp-Dell)# do show running-configuration
...
!
ip dhcp server
!
pool Dell
lease 24
network 20.1.1.0/24
default-router 20.1.1.1
Address lease time
Use the
lease {days [hours] [minutes] | infinite}
command to
configure
an address lease time (default 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.
1
Enable DHCP server-assigned dynamic addresses on an interface in CONFIGURATION mode.
ip dhcp server
System management
449