Re: Question about IPAM tools for v6
On 03/02/2014 11:11, Sam Wilson wrote: Let me de-lurk and make the obvious point that using standard Ethernet addressing would limit the number of nodes on a single link to 2^47, and that would require every unicast address assigned to every possible vendor. Using just the Locally Administered addresses would limit you to 2^46. it bothers me that I can't find any switch with 2^46 ports. Damned vendors. Nick
Re: Question on DHCPv6 address assignment
Fernando Wrt to the Cisco DHCPv6 server (CNR): 1) sequential or random per configuration (can send multiple IA_NA/IA_TA if there are multiple prefixes configured for this link) 2) while client can send a 'hint' to re-use previous addresses, the server can do the same thing, we called this 'affinity', as well if using IA_NA (or course not applicable to IA_TA :-)) PD is the same Hope this helps -éric On 31/01/14 22:00, Fernando Gont ferna...@gont.com.ar wrote: Folks, I'm wondering about the following two aspects of different DHCPv6 implementations out there: 1) What's the pattern with which addresses are generated/assigned? Are they sequential (fc00::1, fc00::2, etc.)? Random? Something else? 2) What about their stability? Is there any intent/mechanism for them to be as stable as possible? Or is it usual for hosts to get a new address for each lease? P.S.: I understand this is likely to vary from one implementation to another... so please describe which implementation/version you're referring to. Thanks! Best regards, -- Fernando Gont e-mail: ferna...@gont.com.ar || fg...@si6networks.com PGP Fingerprint: 7809 84F5 322E 45C7 F1C9 3945 96EE A9EF D076 FFF1
Re: Question about IPAM tools for v6
On 3 Feb 2014, at 11:17, Nick Hilliard n...@foobar.org wrote: On 03/02/2014 11:11, Sam Wilson wrote: Let me de-lurk and make the obvious point that using standard Ethernet addressing would limit the number of nodes on a single link to 2^47, and that would require every unicast address assigned to every possible vendor. Using just the Locally Administered addresses would limit you to 2^46. it bothers me that I can't find any switch with 2^46 ports. Damned vendors. The back of my envelope says that with my vendor of choice and a 4-deep tree (7-hop old-style STP limit) of 384-port switches I can't get more than about 2^34 edge ports. Very disappointing. That would need approximately 57 million routers, though, and 170 GW of electrical power, not counting the cooling requirements. -- Sam Wilson Communications Infrastructure Section, IT Infrastructure Information Services, The University of Edinburgh Edinburgh, Scotland, UK The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336.
Re: Question about IPAM tools for v6
On 3 Feb 2014, at 11:58, Tim Chown t...@ecs.soton.ac.uk wrote: On 3 Feb 2014, at 11:32, Sam Wilson sam.wil...@ed.ac.uk wrote: On 3 Feb 2014, at 11:17, Nick Hilliard n...@foobar.org wrote: On 03/02/2014 11:11, Sam Wilson wrote: Let me de-lurk and make the obvious point that using standard Ethernet addressing would limit the number of nodes on a single link to 2^47, and that would require every unicast address assigned to every possible vendor. Using just the Locally Administered addresses would limit you to 2^46. it bothers me that I can't find any switch with 2^46 ports. Damned vendors. The back of my envelope says that with my vendor of choice and a 4-deep tree (7-hop old-style STP limit) of 384-port switches I can't get more than about 2^34 edge ports. Very disappointing. That would need approximately 57 million routers, though, and 170 GW of electrical power, not counting the cooling requirements. That's a lot of hamsters. Turns out it's more hamsters than we have in the UK. http://www.gridwatch.templar.co.uk/ Sam -- Sam Wilson Communications Infrastructure Section, IT Infrastructure Information Services, The University of Edinburgh Edinburgh, Scotland, UK The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336.
Re: Question on DHCPv6 address assignment
Infoblox uses the ISC DHCP code. I'm thin on details. 1) What's the pattern with which addresses are generated/assigned? Are they sequential (fc00::1, fc00::2, etc.)? Random? Something else? The manual says When the server grants IPv6 leases, it uses an algorithm based on the DUID of the client. 2) What about their stability? Is there any intent/mechanism for them to be as stable as possible? Or is it usual for hosts to get a new address for each lease? I've observed a system obtaining different IPv6 addresses when presenting the same DUID. However, my impression is that hosts usually retain the same address across time. mark
