Добавляем в /etc/sysctl.conf

net.ipv6.conf.default.forwarding=1
net.ipv6.conf.all.forwarding=1

устанавливаем miredo

apt-get install miredo

ping6 ipv6.google.com

Ставим с исходников радиус и настраиваем

vim /usr/local/etc/raddb/sql.conf

sql {
        database = "mysql"
        driver = "rlm_sql_${database}"
        server = "localhost"
        #port = 3306
        login = "radius"
        password = "radsecret"
        radius_db = "radius"
        acct_table1 = "radacct"
        acct_table2 = "radacct"
        postauth_table = "radpostauth"
        authcheck_table = "radcheck"
        authreply_table = "radreply"
        groupcheck_table = "radgroupcheck"
        groupreply_table = "radgroupreply"
        usergroup_table = "radusergroup"
        deletestalesessions = yes
        sqltrace = yes
        sqltracefile = ${logdir}/sqltrace.sql
        num_sql_socks = 5
        connect_failure_retry_delay = 60
        lifetime = 0
        max_queries = 0
        readclients = yes
        nas_table = "nas"
        $INCLUDE sql/${database}/dialup.conf
}

#ls sites-enabled/

default

# cat default

authorize {
        preprocess
        chap
        mschap
        digest
        suffix
        files
        expiration
        logintime
        pap
        sql
}
authenticate {
        Auth-Type PAP {
                pap
        }
        Auth-Type CHAP {
                chap
        }

        Auth-Type MS-CHAP {
                mschap
        }
        digest
        unix
}
preacct {
        preprocess
        acct_unique
        suffix
        files
}
accounting {
        detail
        exec
        attr_filter.accounting_response
}
session {
        radutmp
}
post-auth {
        sql
        exec
        Post-Auth-Type REJECT {
                attr_filter.access_reject
        }
}
pre-proxy {
}
post-proxy {
}

# vim /usr/local/etc/raddb/radiusd.conf

prefix = /usr/local
exec_prefix = ${prefix}
sysconfdir = ${prefix}/etc
localstatedir = /var
sbindir = ${exec_prefix}/sbin
logdir = /var/log
raddbdir = ${sysconfdir}/raddb
radacctdir = ${logdir}/radacct
name = radiusd

confdir = ${raddbdir}
run_dir = ${localstatedir}/run/${name}

db_dir = ${raddbdir}
libdir = /usr/local/lib/freeradius-2.1.12
pidfile = ${run_dir}/${name}.pid
user = freeradius
group = freeradius
max_request_time = 30
cleanup_delay = 5
max_requests = 1024
listen {
        type = auth
        ipaddr = *
        port = 0
}
listen {
        ipaddr = *
#       ipv6addr = ::
        port = 0
        type = acct
}
hostname_lookups = no
allow_core_dumps = no
regular_expressions     = yes
extended_expressions    = yes
log {
        destination = files
        file = ${logdir}/radius.log
        syslog_facility = daemon
        stripped_names = no
        auth = no
        auth_badpass = no
        auth_goodpass = no
}

checkrad = ${sbindir}/checkrad
security {
        max_attributes = 200
        reject_delay = 1
        status_server = yes
}

$INCLUDE clients.conf
thread pool {
        start_servers = 5
        max_servers = 32
        min_spare_servers = 3
        max_spare_servers = 10
        max_requests_per_server = 0
}
modules {
        $INCLUDE ${confdir}/modules/
        $INCLUDE sql.conf
        #  IP addresses managed in an SQL table.
#       $INCLUDE sqlippool.conf
}
instantiate {
        exec
        expr
        expiration
        logintime
}
$INCLUDE policy.conf
$INCLUDE sites-enabled/

добавляем базу и права на нее

CREATE DATABASE radius;
SET PASSWORD FOR 'radius'@'localhost' = PASSWORD('radpass');
GRANT SELECT ON radius.* TO 'radius'@'localhost';
GRANT ALL ON radius.* TO radius@localhost IDENTIFIED BY "radpass";

Добавляем таблицы

#mysql -D radius < schema.sql
#mysql -D radius < nas.sql
#mysql> show tables;

+------------------+
| Tables_in_radius |
+------------------+
| cui              |
| nas              |
| radacct          |
| radcheck         |
| radgroupcheck    |
| radgroupreply    |
| radippool        |
| radpostauth      |
| radreply         |
| radusergroup     |
+------------------+

Заполняем таблицы для тестирования

INSERT INTO radcheck (UserName, Attribute, op, Value) VALUES ('test', 'ClearText-Password', ':=', '123456');
INSERT INTO radreply (UserName, Attribute, op, Value) VALUES ('test', 'Framed-IP-Address', ':=', '192.168.15.1');
INSERT INTO radreply (UserName, Attribute, op, Value) VALUES ('test', 'Framed-IP-Netmask', ':=', '255.255.255.255');
INSERT INTO radreply (UserName, Attribute, op, Value) VALUES ('test', 'Framed-IPv6-Prefix', ':=', '2001:0:c38c:c38c:1804::/64');

#radtest test 123456 localhost 1812 radsecret

Sending Access-Request of id 101 to 127.0.0.1 port 1812
        User-Name = "test"
        User-Password = "123456"
        NAS-IP-Address = 192.168.3.122
        NAS-Port = 1812
rad_recv: Access-Accept packet from host 127.0.0.1 port 1812, id=101, length=52
        Framed-IP-Netmask = 255.255.255.255
        Framed-IP-Address = 192.168.15.1
        Framed-IPv6-Prefix = 2001:0:c38c:c38c:1804::/64

Правим конфигурационный файл /etc/accel-ppp.conf

[modules]
log_file
pptp
pppoe
auth_mschap_v2
radius
sigchld
pppd_compat
#shaper_tbf
ipv6_nd
ipv6_dhcp

[core]
log-error=/var/log/accel-ppp/core.log
thread-count=4

[ppp]
verbose=1
min-mtu=1280
mtu=1400
mru=1400
ipv6=require
ipv6=allow
#ipv6=allow включать только когда клиент запросил
#ipv6=require требовать ipv6
ipv6-intf-id=0:0:0:2
ipv6-peer-intf-id=0:0:0:2
ipv6-accept-peer-intf-id=1

#ipv6-intf-id и ipv6-peer-intf-id читаем rfc5072, rfc4861
если зделали чтобы  радиус передавал префикс 2001:0:c38c:c38c:1804::/64, тогда на стороне сервера адрес будет этот префикс + ipv6-intf-id(из конфига), 
на стороне клиента этот префикс + ipv6-peer-intf-id либо то что предложит клиент если в конфиге ipv6-accept-peer-intf-id=1


[lcp]
echo-interval=30
echo-failure=3

[auth]
#any-login=0
#noauth=0

[pptp]
verbose=1

[pppoe]
interface=eth1
verbose=1


[dns]
dns1=10.0.0.1
#dns2=172.16.1.1

[radius]
dictionary=/usr/local/share/accel-ppp/radius/dictionary
nas-identifier=accel-ppp
nas-ip-address=127.0.0.1
gw-ip-address=10.0.0.1
auth-server=127.0.0.1:1812,radsecret
acct-server=127.0.0.1:1813,radsecret
server=127.0.0.1,radsecret
dae-server=127.0.0.1:3799,testing123
verbose=1
#timeout=3
#max-try=3
#acct-timeout=120
#acct-delay-time=0

[client-ip-range]
10.0.0.0/8

[ip-pool]
gw-ip-address=192.168.0.1

[log]
log-file=/var/log/accel-ppp/accel-ppp.log
log-emerg=/var/log/accel-ppp/emerg.log
log-fail-file=/var/log/accel-ppp/auth-fail.log
copy=1
level=3

[pppd-compat]
#ip-pre-up=/etc/ppp/ip-pre-up
#ip-up=/etc/ppp/ip-up
#ip-down=/etc/ppp/ip-down
#ip-change=/etc/ppp/ip-change
radattr-prefix=/var/run/radattr
verbose=1

[tbf]
#attr=Filter-Id
#down-burst-factor=0.1
#up-burst-factor=1.0
#latency=50

[cli]
telnet=127.0.0.1:2000
tcp=127.0.0.1:2001

[ipv6-dns]
2001:05c0:1000:0011::2
#2001:470:20::2
#dnssl=suffix1.local.net
#dnssl=suffix2.local.net.

[ipv6-dhcp]
verbose=1
pref-lifetime=604800
valid-lifetime=2592000
route-via-gw=1

Подключились Виндовс 7 клиентом смотрим что выдал ПППоЕ сервер