3.52.3. MapAttribute Previous topic Parent topic Child topic Next topic

This optional parameter allows you to specify how the results of the address allocation are to be placed in the reply.
If the yiaddr attribute (usually Framed-IP-Address) is already set in the reply, then AuthBy DYNADDRESS will not allocate an address, and will just ACCEPT the request. This means that if a user record has a fixed IP address in it, then AuthBy DYNADDRESS will not allocate an address for that user.
The above also applies to IPv6 iaaddr and iaprefix. However, if there is additional configuration information, such as DNS server addresses, the allocator may still make a query to fetch this information. For example, DHCPv6 allocator can send a stateless Information-request.
Each MapAttribute specifies the name of the allocation variable, and the name of the RADIUS attribute in which to place it (if it is not set already). The following allocation variables are normally available for IPv4 allocation. Some AddressAllocator clauses may not provide all of these or may also make others available.
  • yiaddr, usually the allocated IP address in dotted quad format (e.g. 1.2.3.4)
  • subnetmask, usually the IP Subnet Mask in dotted quad format (e.g. 255.255.255.255)
  • dnsserver, usually the address of the DNS server to use in dotted quad format (e.g. 1.2.3.4) Only one DNS server address is currently permitted and supported for IPv4
The default behaviour is to place the allocated IPv4 address in Framed-IP-Address, and the IPv4 subnetmask in Framed-IP-Netmask. This is equivalent to:
MapAttribute yiaddr, Framed-IP-Address
MapAttribute subnetmask, Framed-IP-Netmask
There are no default MapAttribute parameters for IPv6 information. For DHCPv6 allocator, the name of the allocation variables must be the case insensitive name of the desired DHCPv6 option. For example, the following requests and maps OPTION_IAADDR and OPTION_DNS_SERVERS. Multiple DNS servers are mapped to multiple instances of DNS-Server-IPv6-Address
MapAttribute iaaddr, Framed-IPv6-Address
MapAttribute dns_servers, DNS-Server-IPv6-Address
For more information about the details of the available allocation variables, see Section 3.112. <AddressAllocator DHCPv6> and Section 3.110. <AddressAllocator SQL>.