= Сообщение: 6709 из 7402 ============================================= IPV6 = От : Victor Sudakov 2:5005/49 04 Jul 21 12:44:50 Кому : Alexey Vissarionov 04 Jul 21 12:44:50 Тема : Two ISPs and backup for a home network (dual-homing) FGHI : area://IPV6?msgid=2:5005/49+60e14ba9 На : area://IPV6?msgid=2:5020/545+60dbd819 = Кодировка сообщения определена как: CP866 ================================== Ответ: area://IPV6?msgid=2:5020/545+60e1ce69 ============================================================================== Dear Alexey,
30 Jun 21 05:24, you wrote to me:
VS>>>> I know that my home router can advertise multiple global IPv6 VS>>>> prefixes into the LAN, but how will LAN hosts failover to the VS>>>> backup gateway if the primary ISP fails? They will have IPv6 VS>>>> addresses from both blocks, which should they choose for their VS>>>> outgoing src address? AV>>> This is the preferred mode of operation, but it has (only) two AV>>> disadvantages: 1. All hosts in the LAN must be able to do the AV>>> switching|balancing on thy own (that means, run Linux; the AV>>> BSD-style networking stack, like the one used in Windoze, has AV>>> very limited functionality). 2. This may require some manual AV>>> configuration on every of them. Not really a problem, but may AV>>> be boring. VS>> This is not feasible because most of those LAN hosts are VS>> smartphones, smart TVs, vacuum cleaners, cameras and other IoT VS>> devices.
AV> Most of these devices have Linux kernel, but crippled userspace.
VS>>>> With two IPv4 ISPs and NAT, the setup is rather trivial, VS>>>> outgoing connections will work via either of the ISPs because VS>>>> the hosts needn't be aware of the failure, and their src VS>>>> private IP is always the same. Can anyone enlighten me? AV>>> This is second option, but you'd lose the main advantage of AV>>> IPv6: the use of publicly routed addresses. VS>> Indeed. I don't like the idea of using NAT in IPv6 even if I VS>> could. So what's the solution?
AV> For dumb devices, especially portable, I'd suggest using NPT.
How well does NPT (being stateless) work with FTP, SIP and other protocols which embed addresses into payload?
AV> Fully AV> functional computers may be connected to some other VLANs (two at once AV> in your case) and configured to use real addresses.
Speaking of those fully functional computers in the LAN, do you mean the setup when there is a script pinging some outside hosts/interfaces and modifying the IPv6 routing table, or something more advanced and interesting?
