Configure DHCPv4 Address Pools

About this task

A pool or range of IP network addresses and DHCP options can be created for each IP interface configured. This range of addresses can be made available to DHCP enabled wireless devices on either a permanent or leased basis. DHCP options are provided to each DHCP client with a DHCP response and provide DHCP clients information required to access network resources (default gateway, domain name, DNS server and WINS server configuration). An option exists to identify the vendor and functionality of a DHCP client. The information is a variable-length string of characters or octets with a meaning specified by the vendor of the DHCP client.

Procedure

  1. Select Policies > DHCPv4.
    The Address Pools dashboard opens.
  2. Select Address Pools.
  3. Select to add a new address pool or to edit an existing address pool option.
    The General tab opens.
  4. Configure the following General settings:
    An alias enables an administrator to define a configuration item (such as a IP address or domain name) once, and then use this single alias across different configurable values.
    Setting Description
    Name If adding a new pool, a name is required. The pool is the range of IP addresses defined for DHCP assignment or lease. The name assigned cannot be modified as part of the edit process. However, if the network pool configuration is obsolete it can be deleted. The name cannot exceed 32 characters
    Subnet Define the IP address, Subnet Mask, or IP alias used for DHCP discovery and requests between the local DHCP server and clients. The IP address and subnet mask (or its alias) are required to match the addresses of the layer 3 interface for the addresses to be supported through that interface. If you are setting a subnet IP alias, ensure that it begins with a dollar sign ($) and does not exceed 32 characters. A numeric IP address is the default setting, not an alias
    Unicast Select true or false
    Boot File Define a boot file name
    BOOTP Next Server Select BOOTP Next Server and define server name
    Lease Time DHCP leases provide addresses for defined times to various clients. If a client does not use the leased address within the defined time, that IP address can be re-assigned to another DHCP supported client. Select this option to assign a lease in seconds (1 - 31,622,399). The default setting is 86,400 seconds
  5. Configure Network settings:
    Domain Name Provide the domain name or domain alias used with this pool. Domain names are not case sensitive and can contain alphabetic or numeric letters or a hyphen. A fully qualified domain name (FQDN) consists of a host name plus a domain name. For example, computername.domain.com. If you are setting a domain name alias, ensure that it begins with a dollar sign ($) and does not exceed 32 characters. A numeric IP address is the default setting, not an alias
    DNS Server Define one (or a group) of Domain Name Servers (DNS) to translate domain names to IP addresses. An alias can alternatively be applied for a DNS server IP address. Up to 8 IP addresses can be supported. If you are setting a DNS IP alias, ensure that it begins with a dollar sign ($) and does not exceed 32 characters. An actual DNS IP address is the default setting, not an alias
    Default Router After a DHCP client has booted, the client begins sending packets to its default router. Set the IP address or IP alias for one or more routers used to map host names into IP addresses for clients. Up to eight default router IP addresses are supported. If setting a default router IP alias, ensure it begins with a dollar sign ($) and does not exceed 32 characters. An actual router IP address is the default setting, not an alias. If you are setting a default router IP alias, ensure that it begins with a dollar sign ($) and does not exceed 32 characters. An actual router IP address is the default setting, not an alias
  6. Configure NetBIOS settings:
    Node Type Select a node type used with this particular pool. The following options are available:
    • Broadcast - Uses broadcasting to query nodes on the network for the owner of a NetBIOS name
    • Peer-to-Peer - Uses directed calls to communicate with a known NetBIOS name server (such as a WINS server), for the IP address of a NetBIOS machine
    • Mixed - A mixed node using broadcast queries to find a node, and failing that, queries a known p-node name server for the address
    • Hybrid - A combination of two or more nodes
    • None - No node type is applied
    Servers Specify a numerical IP address of a single NetBIOS WINS server or a group of servers available to requesting clients.

    A maximum of eight server IP addresses can be assigned. The IP option is selected by default. Optionally select Alias to provide a NetBIOS server IP alias beginning with a dollar sign ($) and not exceeding 32 characters

  7. Define Static Routes settings:
    Destination Define a address pool destination
    Gateway Provide a gateway for the address pool
  8. Define the range of included (starting and ending IP addresses) addresses for this particular pool. Use the Address Range fields for this operation.
    1. Select Add to configure the IP address.
    2. Type a viable range of IP addresses in the IP Start and IP End columns. This is the range of addresses available for assignment to requesting clients.
    3. Select a DHCP Class policy for the IP address range.
  9. Select Add to create an excluded address range.
    Add ranges of IP address to exclude from lease to requesting clients.
    Tip

    Tip

    The best practice is to have ranges of unavailable addresses to ensure IP address resources are in reserve.
  10. Select Add to configure general address pool settings.
  11. Select Advanced tab to configure DHCPv4 pool's advanced settings.
    Domain Name Provide a domain name for DDNS updates representing the forward zone in the DNS server. For example, test.net. The Name option is selected by default. Optionally select Alias to provide a DDNS domain name alias beginning with a dollar sign ($) and not exceeding 32 characters
    TTL Set a TTL (Time to Live) to specify the validity of DDNS records. The maximum value configurable is 864,000 seconds
    Multi User Class Select Multi User Class to associate the user class option names with a multiple user class. This allows the user class to transmit multiple option values to DHCP servers supporting multiple user class options
    Update DNS Set if DNS is updated from a client or a server. Select either Client Update, No Update, or Server Update. The default setting is Do Not Update, implying that no DNS updates occur at all
    Server Specify a numerical IP address of one or two DDNS servers. Dynamic DNS (DDNS) prompts a computer or network to obtain a new IP address lease and dynamically associate a hostname with that address, without having to manually enter the change every time. Since there are situations where an IP address can change, it helps to have a way of automatically updating hostnames that point to the new address every time. The IP option is selected by default. Optionally select Alias to provide a DDNS server IP alias beginning with a dollar sign ($) and not exceeding 32 characters
  12. Select Add to update address pool advanced settings.