Configuring Dns Services For Dhcp Clients - 3Com 5500-SI Configuration Manual

130 C 10: DHCP S
HAPTER
Configuring DNS
Services for DHCP
Clients
C
ERVER ONFIGURATION
The static-bind ip-address command and the static-bind mac-address command can
be executed repeatedly. In this case, the new configuration overwrites the previous
one.
Configuring to assign IP addresses dynamically
IP addresses dynamically assigned to DHCP clients (including those that are
permanently leased and those that are temporarily leased) belong to addresses
segments that are previously specified. Currently, an address pool can contain only
one address segment, whose ranges are determined by the subnet mask.
To avoid IP address conflicts, the IP addresses to be dynamically assigned to DHCP
clients are those that are not occupied by specific network devices (such as gateways
and FTP servers).
The lease time can differ with address pools. But that of the IP addresses of the same
address pool are the same. Lease time is not inherited.
Table 114 Configure to assign IP addresses dynamically
Operation
Enter system view
Create a DHCP address
pool and enter DHCP
address pool view
Set the IP address
segment whose IP address
are to be assigned
dynamically
Configure the lease time
Return to system view
Specify the IP addresses
that are not dynamically
assigned
The network command can be executed repeatedly. In this case, the new
configuration overwrites the previous one.
The dhcp server forbidden-ip command can be executed repeatedly. That is, you can
repeatedly configure IP addresses that are not dynamically assigned to DHCP clients.
If a host accesses the Internet through domain names, DNS (domain name system) is
needed to translate the domain names into the corresponding IP addresses. To enable
DHCP clients to access the Internet through domain names, a DHCP server is required
to provide DNS server addresses while assigning IP addresses to DHCP clients.
Currently, you can configure up to eight DNS server addresses for a DHCP address
pool.
Command Description
system-view -
dhcp server Required
ip-pool pool-name By default, no DHCP address pool is created.
network ip-address Required
[ mask-length | By default, no IP address segment is set. That is,
mask mask ] no IP address is available for being assigned.
expired { day day [ Optional
hour hour [ minute The default lease time is one day.
minute ] ] |
unlimited }
Quit -
dhcp server Optional
forbidden-ip By default, all IP addresses in a DHCP address
low-ip-address [ pool are available for being dynamically
high-ip-address ] assigned.