I got everything configured by book:
dhcpd6 service running.
dhcp6.conf is configured as well as ifcfg-ethX interface file, everything is double checked. There is a csr1000v is running in the same subnet and providing RA packets which I can see it is doing its job.
But f**ing linux dhcpv6 just does not respond to dhcp6 solicit packet, never. Client will get auto-config address as a result.
I usually hate to have linux to do more than basic networking stuff and I'd rather not pursue this but have to do it becuase of job.
If I pluck out just linux dhcpd server from the subnet and plug in samely configured windows dhcp server, it runs right away.
It does respond to solicit packet immediately with offer and then continues and offered ipv6 address is added to pool.
RA is autoconfig, not DHCP.... you do have a separate DHCPv6 server running somewhere?
Are you sending the M flag from the RA to tell the host to ask for DHCP?
yes, csr1000v is sending ra with M flag and O flag clear meaning host uses stateful and DHCP. I can client is sending solicit to all dhcp relay agents ff02::1:2 to which linux does not respond at all. All i see is periodict solicit packets from client. there is a linux utility called dchrelay but does not work as documented and/or poorly documented. I ain't choosing to pursue this wasting my time.
And thus we see what happens when different people choose different implementations of an RFC.
TO get around not dealing with all the crap (after hours of frustration, i can call all the names but would refrain from doing so), there seems to be another workaronud.
Since DHCP for Windows server working nicely, have DHCPv6 served by Windows and transition to TFTP installation once client acquires its DHCPv6 address.
Now the problem is DHCPv4 does appear do this by setting option 66 (specify tftp server), 67 (specify boot file name) in WDS utility. However IPv6 there is no equivalent. as far as windows server is conserned, i can see scope options for ipv6 from the range 00021 to 00032.
I read somewhere there is an equivalent option for tftp/boot file for dhcpv6 albeit with different option No. perhaps if I find it will put it here. Nevertheless whatever that number is, I did not see it in the WDS utility.
Iptables? Selinux?