Comments on: Howto Subnet IPv6 http://www.clarksys.com/blog/2009/03/12/howto-subnet-ipv6/ Rants and Raves! Fri, 12 Feb 2010 03:10:18 +0000 http://wordpress.org/?v=2.9.2 hourly 1 By: Max http://www.clarksys.com/blog/2009/03/12/howto-subnet-ipv6/comment-page-1/#comment-100 Max Thu, 21 May 2009 17:02:46 +0000 http://www.clarksys.com/?p=399#comment-100 Chris, Maybe this will help you (<a href="https://www.arin.net/policy/nrpm.html#six54" rel="nofollow">https://www.arin.net/policy/nrpm.html#six54</a>): <blockquote> > /64 when it is known that one and only one subnet is needed > /56 for small sites, those expected to need only a few subnets over the next 5 years. > /48 for larger sites </blockquote> We will allocate a /48 to any downstream customer that requests one otherwise it is a /56. Anything connected to one of our routers is a /64 nothing larger. We use /126 on all of our connected interfaces with the customer. A /120 in your case for HSRP would fit the bill, we use a second interface via a different device and OSPF costing to facilitate link redundancy. -Max Chris,

Maybe this will help you (https://www.arin.net/policy/nrpm.html#six54):

> /64 when it is known that one and only one subnet is needed
> /56 for small sites, those expected to need only a few subnets over the next 5 years.
> /48 for larger sites

We will allocate a /48 to any downstream customer that requests one otherwise it is a /56. Anything connected to one of our routers is a /64 nothing larger. We use /126 on all of our connected interfaces with the customer. A /120 in your case for HSRP would fit the bill, we use a second interface via a different device and OSPF costing to facilitate link redundancy.

-Max

]]> By: Chris http://www.clarksys.com/blog/2009/03/12/howto-subnet-ipv6/comment-page-1/#comment-99 Chris Thu, 21 May 2009 15:49:29 +0000 http://www.clarksys.com/?p=399#comment-99 Max, Thanks for the information. I feel that not all customers deserve a /48. I work for a Co-location facility and we also have several DSL and ATM customers. So I am looking into the implementation for our customers; If we follow the RFCs and guidelines, then I honestly feel that giving a Co-location customer /48 is a waste of address space if the customer only requires a handful of subnets, it would make more sense to give the customer a /56. We also implement HSRP for customers that have IPv4 connectivity, so when the time comes to implement IPv6 and HSRP (There is anycast), but for now, we are looking at all options and the best scalable method; So in the case with HSRP and IPv6, it does not make sense configuring a vlan interface with a /64. I see that maybe configuring the SVI with a /120 and then routing a /56 or a /48 to the customers router from the /120. I have reviewed many RFCs and the discussion for subnets that are longer than a /64 and what is breaks and so fourth, so I am just trying to get an idea what others have implemented. Thanks for your time. Chris Max,

Thanks for the information. I feel that not all customers deserve a /48. I work for a Co-location facility and we also have several DSL and ATM customers. So I am looking into the implementation for our customers; If we follow the RFCs and guidelines, then I honestly feel that giving a Co-location customer /48 is a waste of address space if the customer only requires a handful of subnets, it would make more sense to give the customer a /56. We also implement HSRP for customers that have IPv4 connectivity, so when the time comes to implement IPv6 and HSRP (There is anycast), but for now, we are looking at all options and the best scalable method; So in the case with HSRP and IPv6, it does not make sense configuring a vlan interface with a /64. I see that maybe configuring the SVI with a /120 and then routing a /56 or a /48 to the customers router from the /120. I have reviewed many RFCs and the discussion for subnets that are longer than a /64 and what is breaks and so fourth, so I am just trying to get an idea what others have implemented.

Thanks for your time.
Chris

]]> By: Max http://www.clarksys.com/blog/2009/03/12/howto-subnet-ipv6/comment-page-1/#comment-95 Max Wed, 20 May 2009 19:53:04 +0000 http://www.clarksys.com/?p=399#comment-95 Chris, I have looked into different IPv6 subnet lengths but because ARIN wants to assign /32s to ISPs and wants the ISP to allocate out a /48 per customer it hasn't been a pressing issue as of yet. Honestly our requirement is assigning a /128 for a router to customer connection and then the /48 for the customer. We've started looking at pushing IPv6 out to our Metro Fiber customers (<a href="http://www.phyber.com/network/ontap.html" rel="nofollow">Phyber ONTAP</a>) but that is probably going to be a slow rollout. -Max Chris,

I have looked into different IPv6 subnet lengths but because ARIN wants to assign /32s to ISPs and wants the ISP to allocate out a /48 per customer it hasn’t been a pressing issue as of yet. Honestly our requirement is assigning a /128 for a router to customer connection and then the /48 for the customer. We’ve started looking at pushing IPv6 out to our Metro Fiber customers (Phyber ONTAP) but that is probably going to be a slow rollout.

-Max

]]> By: Chris http://www.clarksys.com/blog/2009/03/12/howto-subnet-ipv6/comment-page-1/#comment-94 Chris Wed, 20 May 2009 19:43:46 +0000 http://www.clarksys.com/?p=399#comment-94 Your statement ' An IPv6 /32 is 2^16 (65536) /48 subnets ' is assumed for one pop? Have you explored or researched anything longer than a /32 and shorter than a /48; Example, 32 /37s or 64 /38s if an ISP has several POPs and assigning several /37s or /38s to a single pop and so fourth? Thanks Your statement ‘ An IPv6 /32 is 2^16 (65536) /48 subnets ‘ is assumed for one pop? Have you explored or researched anything longer than a /32 and shorter than a /48; Example, 32 /37s or 64 /38s if an ISP has several POPs and assigning several /37s or /38s to a single pop and so fourth? Thanks

]]> By: Max http://www.clarksys.com/blog/2009/03/12/howto-subnet-ipv6/comment-page-1/#comment-91 Max Sun, 17 May 2009 21:57:15 +0000 http://www.clarksys.com/?p=399#comment-91 I've had the same problem trying to find an IPv6 calculator. The problem seems to be that the output is simply too big for any of them to handle. -Max I’ve had the same problem trying to find an IPv6 calculator. The problem seems to be that the output is simply too big for any of them to handle.

-Max

]]> By: Werner http://www.clarksys.com/blog/2009/03/12/howto-subnet-ipv6/comment-page-1/#comment-90 Werner Sun, 17 May 2009 11:10:19 +0000 http://www.clarksys.com/?p=399#comment-90 Thank you, that made IPv6 a little clearer to me. Unfortunately there is no ipv6 calculator on the net that can actually handle the subnetting of a /32 into 65536 /48 Networks :-( http://www.liquidalchemy.com/liquidalchemy/index.php e.g. 2001:f238:/32 into 2^16 /48s doesn't work :D Werner Thank you, that made IPv6 a little clearer to me. Unfortunately there is no ipv6 calculator on the net that can actually handle the subnetting of a /32 into 65536 /48 Networks :-(

http://www.liquidalchemy.com/liquidalchemy/index.php

e.g.
2001:f238:/32 into 2^16 /48s doesn’t work :D

Werner

]]> By: Neetee http://www.clarksys.com/blog/2009/03/12/howto-subnet-ipv6/comment-page-1/#comment-55 Neetee Wed, 22 Apr 2009 15:28:37 +0000 http://www.clarksys.com/?p=399#comment-55 Keep up the good work. Keep up the good work.

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