Configuring Cisco 7206VXR as BRAS

[Frank Bulk]

Mark:

Yes, I'm running stateful DCHPv6.  But I didn't think of PCs that might
directly attach, so stateless DHCPv6 support is a good idea.

Frank

-----Original Message-----
From: ipv6-ops-bounces+frnkblk=iname.com at lists.cluenet.de
[mailto:ipv6-ops-bounces+frnkblk=iname.com at lists.cluenet.de] On Behalf Of
Mark Smith
Sent: Thursday, April 07, 2011 5:49 PM
To: frnkblk at iname.com
Cc: ipv6-ops at lists.cluenet.de
Subject: Re: Configuring Cisco 7206VXR as BRAS

Hi Frank,

On Thu, 7 Apr 2011 17:31:16 -0500
"Frank Bulk" <frnkblk at iname.com> wrote:

> My previous PPPoE testing used the 5th Ethernet port on the DSL modems.
Two
> of the three vendors I've been working with gave me firmware updates
within
> the last week and I moved testing from PPPoE over Ethernet against a test
> 7206VXR to our production DSLAM with our production 7206VXR.
> 
> I got all three working pretty well (the status page in their GUI is
lacking
> in the products) and they appeared to handle /56 delegated prefix OK.
> 
> In reviewing my configuration, I ended removing three commands on my
> Virtual-Template:
>  ipv6 address autoconfig
>  peer default ipv6 pool ipv6pool-lns
>  ipv6 nd other-config-flag
> 
> The first doesn't seem necessary and all it did was add another IPv6
address
> to the WAN interface of the DSL modem.  The second isn't necessary because
I
> use DHCPv6 relay, and the third I changed to "ipv6 nd
managed-config-flag".
> 

Regarding "ipv6 nd other-config-flag", are you using stateful DHCPv6
for addressing or SLAAC for the downstream devices? If it's SLAAC, then
I'd leave "ipv6 nd other-config-flag", on the chance that PCs or
non-CPE/router devices will be used as direct PPPoE clients, and want to
acquire other IPv6 parameters via stateless DHCPv6. The "ipv6 nd
managed-config-flag" would force those PCs to try to use stateful
DHCPv6 to acquire addresses (inherently getting other IPv6 parameters as
well), and would cause that to fail if they don't have a stateful
DHCPv6 client.

> 
> This is my current configuration:
> 
> interface Virtual-Template1
>  mtu 1492
>  ip unnumbered Loopback11
>  ip access-group 125 in
>  ip verify unicast source reachable-via rx 126
>  ip mtu 1492
>  ip tcp adjust-mss 1452
>  no logging event link-status
>  peer default ip address dhcp
>  ipv6 unnumbered Loopback11
>  ipv6 enable
>  no ipv6 nd suppress-ra
>  ipv6 nd managed-config-flag
>  ipv6 dhcp relay destination DEAD:BEEF:0:1000::7
>  ppp mtu adaptive
>  ppp authentication pap radius-group-aaa
>  ppp ipcp dns <IPv4 addresses>
>  ppp ipcp address unique
> end
> 
> interface Loopback11
>  <snip IPv4 addresses>
>  ip route-cache same-interface
>  ipv6 address DEAD:BEEF:4000::1/64
>  ipv6 enable
> end
> 
> 
> Any recommendations for improvement or advice?
> 
> Frank
> 

Regards,
Mark.