default RA lifetime and hoplimit not set in route

[ColinMcInnes]

the default route is being sent by the router via RA, and they are setting a lifetime of 1800s and a hop limit of 64. However this is not showing up in the ip -6 route show.

$ ip -6 route show ::/0
default via fe80::2efa:a2ff:fe90:e275 dev eth0 proto ra metric 1002 pref medium

$ dhcpcd -U eth0
reason=ROUTERADVERT
interface=eth0
protocol=ra
nd1_from=fe80::2efa:a2ff:fe90:e275
nd1_acquired=1100
nd1_now=1152
nd1_hoplimit=64
nd1_flags=M
nd1_lifetime=1800
nd1_source_address=2cfaa290e275
nd1_prefix_information1_length=64
nd1_prefix_information1_flags=L
nd1_prefix_information1_vltime=2592000
nd1_prefix_information1_pltime=604800
nd1_prefix_information1_prefix=2001:192:168:228::

dhcpcd 10.1.0 linux

here's what it looks like if I use ISC's dhclient 4.4.3

default via fe80::2efa:a2ff:fe90:e275 dev eth0 proto ra metric 1024 expires 1609sec hoplimit 64 pref medium

Any ideas where to start looking?

[ColinMcInnes]

Found it, in if-linux and ipv6. I'll create a patch to send it to netlink.

[rsmarples]

ISC dhclient doesn't set any routes, just addresses.
Something Else (TM) must be setting the routes :)

dhcpcd will expire the routes anyway, so any fix we do is purely cosmetic (unless of course dhcpcd has stopped for whatever reason)

[ColinMcInnes]

dhcpcd will expire the routes anyway, so any fix we do is purely cosmetic (unless of course dhcpcd has stopped for whatever reason)

Yes, I agree it's purely cosmetic. I have some other code that reports the current route lifetime from nl, so this is why I'm adding it for informational purposes.

ISC dhclient doesn't set any routes, just addresses. Something Else (TM) must be setting the routes :)

I found that out once I started looking deeper. :)

[rsmarples]

If it helps, hop limit is defined here in the kernel: https://elixir.bootlin.com/linux/v6.12.6/source/include/uapi/linux/rtnetlink.h#L485

So it's a property of RTA_METRICS. Good luck!