Re: rtadvd(8) How to IPv6 tokenize interface identifier

From: Karl Denninger <karl_at_denninger.net>
Date: Fri, 21 Feb 2025 23:31:15 UTC
On 2/21/2025 18:15, Roy Marples wrote:
> Well,  it sounds good!
> But I would rather you don't screw the pooch if the network fails and it's a pain to recover :/
>
> Saying that, you could setup a static address on the box so you can get to it over the LAN even if dhcpcd fails.
> If it's the WAN interface you expect to get access over, yes that could be an issue and I'd rather you be on site in this instance.
> Save the pain!
>
> Good luck
>
> Roy

That *_does_* appear to work; on boot from a power-cycle it properly got 
Ipv6 addresses and delegated them to the appropriate interfaces internally.

$ ifconfig igb0: 
flags=1008843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST,LOWER_UP> metric 0 
mtu 1500 
options=4e527bb<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,JUMBO_MTU,VLAN_HWCSUM,TSO4,TSO6,LRO,WOL_MAGIC,VLAN_HWFILTER,VLAN_HWTSO,RXCSUM_IPV6,TXCSUM_IPV6,HWSTATS,MEXTPG> 
ether 00:0d:b9:46:71:88 inet 71.15.252.132 netmask 0xfffffc00 broadcast 
255.255.255.255 inet6 fe80::20d:b9ff:fe46:7188%igb0 prefixlen 64 scopeid 
0x1 inet6 2600:6c5d:7009:600:3d16:3857:8d9f:9b29 prefixlen 128 pltime 
3600 vltime 3600 media: Ethernet autoselect (1000baseT <full-duplex>) 
status: active nd6 options=1<PERFORMNUD> igb1: 
flags=1008843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST,LOWER_UP> metric 0 
mtu 1500 
options=4e1203b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,JUMBO_MTU,WOL_MAGIC,VLAN_HWFILTER,RXCSUM_IPV6,TXCSUM_IPV6,HWSTATS,MEXTPG> 
ether 00:0d:b9:46:71:89 inet 192.168.10.200 netmask 0xffffff00 broadcast 
192.168.10.255 inet 192.168.2.200 netmask 0xffffff00 broadcast 
192.168.2.255 inet6 fe80::20d:b9ff:fe46:7189%igb1 prefixlen 64 scopeid 
0x2 inet6 2600:6c5d:5d00:fb00::1 prefixlen 64 pltime 3600 vltime 3600 
media: Ethernet autoselect (1000baseT <full-duplex>) status: active nd6 
options=21<PERFORMNUD,AUTO_LINKLOCAL> lo0: 
flags=1008049<UP,LOOPBACK,RUNNING,MULTICAST,LOWER_UP> metric 0 mtu 16384 
options=680003<RXCSUM,TXCSUM,LINKSTATE,RXCSUM_IPV6,TXCSUM_IPV6> inet 
127.0.0.1 netmask 0xff000000 inet6 ::1 prefixlen 128 inet6 fe80::1%lo0 
prefixlen 64 scopeid 0x3 groups: lo nd6 
options=21<PERFORMNUD,AUTO_LINKLOCAL>

This did /not /work before (unless you killed and restarted it you only 
get an IPv4 address) and does now, so there you go.

143 - SC 0:00.21 dhcpcd: [manager] [ip4] [ip6] (dhcpcd) 144 - S 0:00.25 
dhcpcd: [privileged proxy] (dhcpcd) 145 - SC 0:00.02 dhcpcd: [network 
proxy] (dhcpcd) 146 - SC 0:00.01 dhcpcd: [control proxy] (dhcpcd) 600 - 
IC 0:00.00 dhcpcd: [BPF ARP] igb0 71.15.252.132 (dhcpcd)

I presume rtadvd still has to run to distribute routes, yes?

I'm not COMPLETELY sure everything works as expected on an immediate 
basis but the box did come up, did get a delegation and my clients got 
SLACC addresses as expected so "first blush" it looks good.

--
Karl Denninger
karl@denninger.net
/The Market Ticker/
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