Description

This article provides an example on how to assign fixed IPv4 address and IPv6 prefix for a Dual Stack PPPoE subscriber.

In this example, the radius server is Freeradius.

Solution

Topology:

Dual Stack PPPoE subscriber <----> (xe-0/2/0)MX(ge-0/0/0) <----> Radius Server

In this example, two users are created to verify the result.

  • User "pppoe" will get dynamic addresses from pool, which configured on MX.
  • User "pppoe-u1" will get a fixed IPv4 address and ndra+dhcpv6-pd prefixes, which is assigned by radius server.
First, check if relevant standard files have been included into "dictionary" file: 
[root@radius ~]# more /usr/local/share/freeradius/dictionary | egrep "2865|3162|4818"
$INCLUDE dictionary.rfc2865
$INCLUDE dictionary.rfc3162
$INCLUDE dictionary.rfc4818
The RFC files above includes the following attributes, which is needed to use in this example: 
[root@radius ~]# more /usr/local/share/freeradius/dictionary.rfc2865 | grep "Framed-IP-Address"
ATTRIBUTE	Framed-IP-Address			8	ipaddr

[root@radius ~]# more /usr/local/share/freeradius/dictionary.rfc3162 | grep "Framed-IPv6-Prefix"
ATTRIBUTE	Framed-IPv6-Prefix			97	ipv6prefix

[root@radius ~]# more /usr/local/share/freeradius/dictionary.rfc4818 | grep "Delegated-IPv6-Prefix"
ATTRIBUTE	Delegated-IPv6-Prefix			123	ipv6prefix
By default, Freeradius included those files. You may need to add "$INCLUDE dictionary.rfc4818" in the dictionary file.

Then add the following two users in the file of "/usr/local/etc/raddb/users" as follows: 
pppoe    Cleartext-Password := "$ABC123"
         Service-Type = Framed-User,
         Framed-Protocol = PPP

pppoe-u1    Cleartext-Password := "$ABC123"
            Service-Type = Framed-User,
            Framed-Protocol = PPP,
            Framed-IPv6-Prefix = "fec0:1:1:1::/64",
            Delegated-IPv6-Prefix = "fec0:1:1:1000::/64",
            Framed-IP-Address = 3.3.3.3

MX configuration example: 

dynamic-profiles {
    dyn-pppoe {
        interfaces {
            pp0 {
                unit "$junos-interface-unit" {
                    no-traps;
                    ppp-options {
                        chap;
                        pap;
                    }
                    pppoe-options {
                        underlying-interface "$junos-underlying-interface";
                        server;
                    }
                    family inet {
                        unnumbered-address lo0.0;
                    }
                    family inet6 {
                        address $junos-ipv6-address;
                    }
                }
            }
        }
        protocols {
            router-advertisement {
                interface "$junos-interface-name" {
                    other-stateful-configuration;
                    prefix $junos-ipv6-ndra-prefix;
                }
            }
        }
    }
    dyn-vlan {
        interfaces {
            "$junos-interface-ifd-name" {
                unit "$junos-interface-unit" {
                    no-traps;
                    vlan-id "$junos-vlan-id";
                    family pppoe {
                        dynamic-profile dyn-pppoe;
                    }
                }
            }
        }
    }
}
system {
    services {
        dhcp-local-server {
            dhcpv6 {
                overrides {
                    process-inform {
                        pool v6-ndra-p1;
                    }
                    delegated-pool v6-pd-p1;
                }
                group v6-ppp {
                    interface pp0.0;
                }
            }
        }
    }
}
access-profile dyn-radius;
interfaces {
    ge-0/0/0 {
        unit 0 {
            family inet {
                address 9.0.0.1/24;
            }
        }
    }        
    xe-0/2/0 {
        flexible-vlan-tagging;
        auto-configure {
            vlan-ranges {
                dynamic-profile dyn-vlan {
                    accept pppoe;
                    ranges {
                        1-4094;
                    }
                }
            }
        }
    }
    lo0 {
        unit 0 {
            family inet {
                address 1.1.1.1/32;
            }
        }
    }
}
access {
    group-profile dns-server {
        ppp {
            primary-dns 8.8.8.8;
            secondary-dns 8.8.4.4;
        }
    }
    profile dyn-radius {
        authentication-order radius;
        radius {
            authentication-server 9.0.0.9;
            accounting-server 9.0.0.9;
        }
        radius-server {
            9.0.0.9 {
                port 1812;
                accounting-port 1813;
                secret "$ABC123"; ## SECRET-DATA
                source-address 1.1.1.1;
            }
        }
        accounting {
            order radius;
            accounting-stop-on-failure;
            accounting-stop-on-access-deny;
            coa-immediate-update;
            update-interval 10;
            statistics volume-time;
        }
    }
    address-assignment {
        neighbor-discovery-router-advertisement v6-ndra-p1;
        pool pppoe-p1 {
            family inet {
                network 3.1.0.0/16;
                range p1 {
                    low 3.1.0.2;
                    high 3.1.100.254;
                }
                xauth-attributes {
                    primary-dns 8.8.8.8/32;
                    secondary-dns 8.8.4.4/32;
                }
            }
        }
        pool v6-ndra-p1 {
            family inet6 {
                prefix 3001::/48;
                range v6-ndra-p1-r1 prefix-length 64;
                dhcp-attributes {
                    dns-server {
                        2222::5;
                        2222::6;
                    }
                }
            }
        }
        pool v6-pd-p1 {
            family inet6 {
                prefix 3000::/48;
                range v6-pd-p1-r1 prefix-length 64;
                dhcp-attributes {
                    dns-server {
                        2222::3;
                        2222::4;
                    }
                }
            }
        }
    }
    address-protection;
}

Verification

User “pppoe” got dynamic addresses from pool and user "pppoe-u1" got fixed address which is assigned by the radius server: 
user@mx> show subscribers user-name pppoe
Interface             IP Address/VLAN ID                      User Name                      LS:RI
pp0.3221225474        3.1.0.2                                 pppoe                     default:default
*                     3000::/64
*                     3001::/64

user@mx> show subscribers user-name pppoe-u1
Interface             IP Address/VLAN ID                      User Name                      LS:RI
pp0.3221225473        3.3.3.3                                 pppoe-u1                  default:default
*                     fec0:1:1:1000::/64
*                     fec0:1:1:1::/64