| 2 Jun 2025 |
 hexa | if you only have one LAN interface it doesn't matter | 00:18:54 |
| hexa | but once you have multiple you'll see that each gets its own /64 | 00:19:14 |
| hexa | multiple LAN interfaces may make sense if you intend to separate them for any reason | 00:19:40 |
| hexa | iot/things, guests, wlan/lan, management, you name it | 00:20:04 |
 Charles | hmm to be clear i think i just want a single "network", at least right now, my router has 4 physical ports, one is wan and 3 are bridged as lan, shouldn't one /64 be sufficient for that? | 00:21:10 |
| hexa | yeah | 00:21:28 |
| hexa | once you don't bridge and use the ports individually, or you start using vlans, that'll change | 00:21:50 |
| hexa | also, your isp may be shit (it probably is) and only give you another /64 😄 | 00:22:54 |
| hexa | which is stupid, because they have lots of ipv6 address space | 00:23:11 |
| Charles | [root@green:~]# ip -6 route
2001:558:100d:5a::/64 dev en-wan proto ra metric 1024 expires 2591998sec pref medium
2601:1c1:8400:a440::/64 dev br-lan proto kernel metric 256 expires 341762sec pref medium
unreachable 2601:1c1:8400:a440::/60 dev lo proto dhcp metric 1024 pref medium
fd00:0:d:4::/64 dev en-wan proto ra metric 1024 expires 2591998sec pref medium
fd00:0:101:41::/64 dev en-wan proto ra metric 1024 expires 2591998sec pref medium
fe80::/64 dev br-lan proto kernel metric 256 pref medium
fe80::/64 dev en-wan proto kernel metric 256 pref medium
default nhid 3750293650 via fe80::21c:73ff:fe00:99 dev en-wan proto ra metric 1024 expires 1798sec pref medium
| 00:23:27 |
| hexa |
I just tried requesting a /56 with dhcpcd, but Comcast only gave me a /60 in return. Were you able to get a /56 on consumer Xfinity?
| 00:23:31 |
| Charles | does that unreachable line mean i actually have a /60? | 00:23:51 |
| hexa | a /60 would support 2^(64-60) /64 subnets | 00:23:55 |
| hexa | yes, it does | 00:24:15 |
| hexa | unreachable 2001:16b8:b426:6500::/56 dev lo proto dhcp metric 1024 pref medium
| 00:24:25 |
| hexa | 🙂 | 00:24:29 |
| Charles | i dismissed that line since it says unreachable and also says lo instead of en-wan lol | 00:25:02 |
| Charles | lucky you lol | 00:25:08 |
| hexa | * a /60 would support 2^(64-60) = 16 /64 subnets | 00:25:10 |
| hexa | well it means it terminates locally | 00:25:22 |
| hexa | it doesn't send traffic toward it over wAN | 00:25:28 |
| hexa | * it doesn't send traffic toward it over WAN | 00:25:30 |
| Charles | ah | 00:25:36 |
| hexa | and now you configure more specific routes and they'll get preferred | 00:25:51 |
| hexa | but the unreachable route is the fallback for all unrouted addresses in that /60 | 00:26:08 |
| hexa | and now you have a /64 on br-lan | 00:26:39 |
| hexa | and with IPv6SendRA, that should be everything needed to get started | 00:27:02 |
| Charles | yeah, i have this on my desktop now:
2: eno1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
link/ether c8:7f:54:08:e0:65 brd ff:ff:ff:ff:ff:ff
altname enp10s0
altname enxc87f5408e065
inet 192.168.0.125/24 brd 192.168.0.255 scope global dynamic noprefixroute eno1
valid_lft 2837sec preferred_lft 2837sec
inet6 2601:1c1:8400:a440:9429:7b29:796:713c/64 scope global temporary dynamic
valid_lft 3182sec preferred_lft 1382sec
inet6 2601:1c1:8400:a440:5147:4347:6751:f7ca/64 scope global dynamic mngtmpaddr noprefixroute
valid_lft 3182sec preferred_lft 1382sec
inet6 fe80::b8a:6432:e26c:787c/64 scope link noprefixroute
valid_lft forever preferred_lft forever
| 00:27:17 |
| hexa | ping 2600:: | 00:27:31 |
| Charles | ┌─[~]
└─[charles@compy]$ dig AAAA google.com +short
2607:f8b0:400a:80a::200e
┌─[~]
└─[charles@compy]$ ip route get 2607:f8b0:400a:806::200e
2607:f8b0:400a:806::200e from :: via fe80::10b8:f6ff:fef0:f963 dev eno1 proto ra src 2601:1c1:8400:a440:9429:7b29:796:713c metric 100 pref medium
and curl -6 google.com hangs and then times out lol
| 00:27:44 |
