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RA only?

Open traud opened this issue 3 years ago • 2 comments

The readme claims a mode which relies just on IPv6 Router Advertisements (RA). I am not able to find that mode. However, I need that because I am using my OpenWrt device not as router but as simple Wi-Fi access point. And my upstream router has no DHCPv6 server, even not a stateless one. I know, this tool is called from its shell script /package/network/ipv6/odhcp6c/files/dhcpv6.sh normally. And that script is started with options from /etc/config/network. Anyway, three teared down examples called directly from the command line, to eased debugging with Wireshark:

odhcp6c br-lan

creates continuously a DHCPv6 solicit, because the state is is DHCPV6_UNKNOWN (-N is try).

odhcp6c -N none br-lan

creates continuously a DHCPv6 information-request, because the state is DHCPV6_STATELESS.

odhcp6c -N none -P 64 br-lan

creates continuously a DHCPv6 solicit, because the state is DHCPV6_UNKNOWN.

I went through the blame history and it looks like this never worked. Yes, IPv6 still works. However, I do not like to pollute my network with DHCPv6 messages; especially because in the RA, the m(anaged) and o(ther) bits are off.

traud avatar Apr 30 '21 16:04 traud

Any comment, at least a confirmation? Then, I could start a Pull Request (which first changes the Read Me).

traud avatar May 25 '21 16:05 traud

A RA mode only, in the sense of only listening to RAs and not sending DHCPv6 messages, has never been supported. Internally there's a mechanism (controllable via the -F and -S options) which allows the ra-updated event to be raised without the DHCPv6 client being in bound mode; this is meant as the RA-only mode in the README

dedeckeh avatar May 30 '21 19:05 dedeckeh