[Dnsmasq-discuss] WG: AW: AW: clients of DHCPv6 with constructed IPv6 address range are not notified on address range change
Hello Simon, the patch seems to work reliable, I've not seen any glitches so far. I'd suggest to apply it to main branch. -Ursprüngliche Nachricht- Von: Andrey Vakhitov Gesendet: Samstag, 6. Oktober 2018 20:31 An: 'Simon Kelley' ; 'dnsmasq-discuss@lists.thekelleys.org.uk' Betreff: AW: AW: AW: [Dnsmasq-discuss] clients of DHCPv6 with constructed IPv6 address range are not notified on address range change Hello Simon, >> I've reactivated the patch locally and observing it since 4 days. >> Todays night associated >> IPv6 names got lost again directly during IP prefix change process, >> the log shows it clearly (see log 1). So I would vote again for >> retrying during some extended timeframe even if the host isn't reachable. > OK, done. Patch is here: > > http://thekelleys.org.uk/gitweb/?p=dnsmasq.git;a=commit;h=ee1df06aabaa > 8f212eaa7102f6d62cb25bfb35e9 Thanks a lot for your great support! I've applied the patch and will monitor the behaviour. Best Regards, -- Andrey Vakhitov E-Mail: and...@vakhitov.netStuttgart, Germany ___ Dnsmasq-discuss mailing list Dnsmasq-discuss@lists.thekelleys.org.uk http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss
Re: [Dnsmasq-discuss] clients of DHCPv6 with constructed IPv6 address range are not notified on address range change
Hello Simon, >> I've reactivated the patch locally and observing it since 4 days. Todays >> night associated >> IPv6 names got lost again directly during IP prefix change process, the log >> shows it clearly >> (see log 1). So I would vote again for retrying during some extended >> timeframe even if the >> host isn't reachable. > OK, done. Patch is here: > > http://thekelleys.org.uk/gitweb/?p=dnsmasq.git;a=commit;h=ee1df06aabaa8f212eaa7102f6d62cb25bfb35e9 Thanks a lot for your great support! I've applied the patch and will monitor the behaviour. Best Regards, -- Andrey Vakhitov E-Mail: and...@vakhitov.netStuttgart, Germany ___ Dnsmasq-discuss mailing list Dnsmasq-discuss@lists.thekelleys.org.uk http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss
Re: [Dnsmasq-discuss] clients of DHCPv6 with constructed IPv6 address range are not notified on address range change
vertisement on 2001:16b8:2220:4ffc::, constructed for lan0 Okt 02 04:26:14 rtr dnsmasq-dhcp[11540]: router advertisement on 2001:16b8:2220:4ffd::, old prefix for dmz0 Okt 02 04:26:14 rtr dnsmasq-dhcp[11540]: DHCPv6 stateless on 2001:16b8:2220:4ffd::, constructed for dmz0 Okt 02 04:26:14 rtr dnsmasq-dhcp[11540]: DHCPv4-derived IPv6 names on 2001:16b8:2220:4ffd::, constructed for dmz0 Okt 02 04:26:14 rtr dnsmasq-dhcp[11540]: router advertisement on 2001:16b8:2220:4ffd::, constructed for dmz0 Okt 02 04:26:14 rtr dhcpcd[15287]: dmz0: adding route to 2001:16b8:2220:4ffd::/64 Okt 02 04:26:14 rtr dhcpcd[15287]: wan0: executing `/usr/lib/dhcpcd/dhcpcd-run-hooks' BOUND6 Okt 02 04:26:14 rtr dhcpcd[15287]: wan0: Router Advertisement DAD completed Okt 02 04:26:14 rtr dhcpcd[15287]: wan0: executing `/usr/lib/dhcpcd/dhcpcd-run-hooks' ROUTERADVERT - Best Regards, -- Andrey Vakhitov E-Mail: and...@vakhitov.netStuttgart, Germany ___ Dnsmasq-discuss mailing list Dnsmasq-discuss@lists.thekelleys.org.uk http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss
Re: [Dnsmasq-discuss] clients of DHCPv6 with constructed IPv6 address range are not notified on address range change
Hello Simon, > If you look, lots of things are different between the two logs. In the second one, > dhcpcd is doing routing table changes, for instance. That could explain why dnsmasq > gives up trying to confirm SLAAC addresses because it gets transient "no route to host" > returns. (see previous reply to make sense of this.) Ok, change of the routing is actually the "normal case" for me in this scenario. Once again: My ISP requires nightly reconnect. After the reconnect IPv6 address range assigned by IPS changes normally. Delegated prefixes allocated by upstream router are changing also. Addresses of internal interfaces there dnsmasq provides DHCP & DNS services are changing as well (new prefix). And this is exactly the reason why I want to utilize "ra-names" option: IPv6 prefixes are changing every day and I need name resolution to reach hosts via IPv6. Best Regards, -- Andrey Vakhitov E-Mail: and...@vakhitov.net Stuttgart, Germany ___ Dnsmasq-discuss mailing list Dnsmasq-discuss@lists.thekelleys.org.uk http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss
Re: [Dnsmasq-discuss] WG: clients of DHCPv6 with constructed IPv6 address range are not notified on address range change
TR-ADVERT(dmz0) 2001:16b8:22c4:83fd:: Sep 18 04:35:48 rtr dnsmasq-dhcp[7855]: RTR-ADVERT(dmz0) 2001:16b8:2285:3afd:: old prefix Sep 18 04:35:48 rtr dnsmasq-dhcp[7855]: DHCPINFORMATION-REQUEST(dmz0) 00:02:00:00:ab:11:9b:74:21:c0:e9:5d:1c:18 Sep 18 04:35:51 rtr dnsmasq-dhcp[7855]: RTR-ADVERT(dmz0) 2001:16b8:22c4:83fd:: Sep 18 04:35:51 rtr dnsmasq-dhcp[7855]: RTR-ADVERT(dmz0) 2001:16b8:2285:3afd:: old prefix Sep 18 04:35:51 rtr dnsmasq-dhcp[7855]: DHCPINFORMATION-REQUEST(dmz0) 00:02:00:00:ab:11:9b:74:21:c0:e9:5d:1c:18 Sep 18 04:35:54 rtr dnsmasq-dhcp[7855]: RTR-ADVERT(lan0) 2001:16b8:22c4:83fc:: Sep 18 04:35:54 rtr dnsmasq-dhcp[7855]: RTR-ADVERT(lan0) 2001:16b8:2285:3afc:: old prefix Sep 18 04:35:54 rtr dnsmasq-dhcp[7855]: RTR-ADVERT(lan0) 2001:16b8:22c4:83fc:: Sep 18 04:35:54 rtr dnsmasq-dhcp[7855]: RTR-ADVERT(lan0) 2001:16b8:2285:3afc:: old prefix Sep 18 04:35:54 rtr dnsmasq-dhcp[7855]: DHCPINFORMATION-REQUEST(lan0) 00:02:00:00:ab:11:ee:62:d8:4d:ca:9f:9d:d5 Sep 18 04:35:54 rtr dnsmasq-dhcp[7855]: DHCPINFORMATION-REQUEST(lan0) 00:02:00:00:ab:11:d5:97:98:17:01:41:27:3e Sep 18 04:35:58 rtr dnsmasq-dhcp[7855]: RTR-ADVERT(dmz0) 2001:16b8:22c4:83fd:: Sep 18 04:35:58 rtr dnsmasq-dhcp[7855]: RTR-ADVERT(dmz0) 2001:16b8:2285:3afd:: old prefix Sep 18 04:35:58 rtr dnsmasq-dhcp[7855]: DHCPINFORMATION-REQUEST(dmz0) 00:02:00:00:ab:11:9b:74:21:c0:e9:5d:1c:18 Sep 18 04:36:00 rtr dnsmasq-dhcp[7855]: RTR-ADVERT(dmz0) 2001:16b8:22c4:83fd:: Sep 18 04:36:00 rtr dnsmasq-dhcp[7855]: RTR-ADVERT(dmz0) 2001:16b8:2285:3afd:: old prefix Sep 18 04:36:00 rtr dnsmasq-dhcp[7855]: DHCPINFORMATION-REQUEST(dmz0) 00:02:00:00:ab:11:9b:74:21:c0:e9:5d:1c:18 Sep 18 04:36:01 rtr dnsmasq-dhcp[7855]: RTR-ADVERT(lan0) 2001:16b8:22c4:83fc:: Sep 18 04:36:01 rtr dnsmasq-dhcp[7855]: RTR-ADVERT(lan0) 2001:16b8:2285:3afc:: old prefix Sep 18 04:36:01 rtr dnsmasq-dhcp[7855]: DHCPINFORMATION-REQUEST(lan0) 00:02:00:00:ab:11:ee:62:d8:4d:ca:9f:9d:d5 Sep 18 04:36:01 rtr dnsmasq-dhcp[7855]: DHCPINFORMATION-REQUEST(lan0) 00:02:00:00:ab:11:d5:97:98:17:01:41:27:3e Sep 18 04:36:08 rtr dnsmasq-dhcp[7855]: RTR-ADVERT(dmz0) 2001:16b8:22c4:83fd:: Sep 18 04:36:08 rtr dnsmasq-dhcp[7855]: RTR-ADVERT(dmz0) 2001:16b8:2285:3afd:: old prefix Sep 18 04:36:08 rtr dnsmasq-dhcp[7855]: DHCPINFORMATION-REQUEST(dmz0) 00:02:00:00:ab:11:9b:74:21:c0:e9:5d:1c:18 Sep 18 04:36:10 rtr dnsmasq-dhcp[7855]: RTR-ADVERT(lan0) 2001:16b8:22c4:83fc:: Sep 18 04:36:10 rtr dnsmasq-dhcp[7855]: RTR-ADVERT(lan0) 2001:16b8:2285:3afc:: old prefix - Best Regards, -- Andrey Vakhitov E-Mail: and...@vakhitov.net Stuttgart, Germany ___ Dnsmasq-discuss mailing list Dnsmasq-discuss@lists.thekelleys.org.uk http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss
[Dnsmasq-discuss] WG: clients of DHCPv6 with constructed IPv6 address range are not notified on address range change
Hello Uwe, >> My recommendation to the reporter: >> - Don't use stateful DHCPv6 in Germany, that does not work well. You >> clients should get the addresses using router advertisements. For static hosts assign static names in your own domain. The "ra-names" >> assigns both the IPv4 and IPv6 address to the SLAAC name, so lookup >> works fine. With router advertisements, DNSmasq will send "deprecated" > As you correctly recognized, the reason for usage of stateful DHCPv6 was to get correct dynamic name resolution for IPv6. > I also see the combination of DHCPv4 with SLAAC as possible workaround, I've to try it I've set it up as you suggested, initially name resolution seems to work fine. But after some days of operation (and some nightly reconnects) dnsmasq seems to loose associated IPv6 adresses: DNS request reports only IPv6 address assigned via DHCP. The SLAAC-based IPv6 addresses on hosts are present and correct. How can I investigate and fix this issue? Best regards, -- Andrey Vakhitov E-Mail: and...@vakhitov.netStuttgart, Germany ___ Dnsmasq-discuss mailing list Dnsmasq-discuss@lists.thekelleys.org.uk http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss ___ Dnsmasq-discuss mailing list Dnsmasq-discuss@lists.thekelleys.org.uk http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss
Re: [Dnsmasq-discuss] clients of DHCPv6 with constructed IPv6 address range are not notified on address range change
Hello Simon & Uwe, > unfortunately that problem is seen often with providers in Germany, although > the large ones no longer > do it (or allow to disable the disconnect). The problem is that German > providers automatically > disconnect the PPPoE connection every 24 hrs. After reconnecting you get a > new address (IPv4) and > prefix (IPv6). Since the changes we did (deprecating prefixes) this works > fine for standard router > advertisements. But won't help for DHCPv6. This is exactly my case, my ISP is o2. >> Dnsmasq doesn't implement RECONFIGURE. It probably should. The main >> problem, from a quick look at the RFC, is that RECONFIGURE mandates >> use of security mechanism, and dnsmasq doesn't implement that either! I know that it's against RFC but some routers (like the fritzbox I'm using, very popular choice in Germany) actually send RECONFIGURE without authentication. This is BTW the reason for introduction of "noauthrequired" config option in dhcpcd ;-) > My recommendation to the reporter: > - Don't use stateful DHCPv6 in Germany, that does not work well. You clients > should get the addresses > using router advertisements. For static hosts assign static names in your own > domain. The "ra-names" > assigns both the IPv4 and IPv6 address to the SLAAC name, so lookup works > fine. With router > advertisements, DNSmasq will send "deprecated" prefixes for some time when it > figures out that the > prefix changed and sends the new prefix at the same time. This allows to have > no interruption (except > the forced PPP disconnect). In general, in IPv6 world you should forget about > static addresses, it's also > better for privacy. As you correctly recognized, the reason for usage of stateful DHCPv6 was to get correct dynamic name resolution for IPv6. My IPv4 setup utilizes static addresses, I didn't used DHCPv4 for hosts acting as servers. I also see the combination of DHCPv4 with SLAAC as possible workaround, I've to try it. My problem with this setup is the lack of fallback address in networkd DHCP client: If DHCPv4 fails due to any reason the host get some "weird" address. Static IPv4 setup is free from this drawback and wanted to keep it as is and complement it with IPv6 solution... Best regards, -- Andrey Vakhitov E-Mail: and...@vakhitov.netStuttgart, Germany ___ Dnsmasq-discuss mailing list Dnsmasq-discuss@lists.thekelleys.org.uk http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss
[Dnsmasq-discuss] clients of DHCPv6 with constructed IPv6 address range are not notified on address range change
Thanks for a great dnsmasq software. I'm using dnsmasq 2.79 in combination with IPv6 prefix delegation. The prefixes are changing daily due to daily reconnect of upstream router. Dhcpcd is used to handle prefix delegation on external interface and apply new address to internal interface (dmz0). Dnsmasq picks up the prefix assigned to the internal interface by dhcpcd and server RA and DHCPv6 server. dhcp-range=set:dmz6,::,constructor:dmz0,ra-stateless,ra-names dhcp-host=id:00:02:00:00:ab:11:9b:74:21:c0:e9:5d:1c:18,set:dmzfix6,[::56],dm zhost Initially the host gets IPv6 address via DHCPv6 correctly, DNS resolution works as expected, everything seems to be ok. But after reconnect (and according prefix change) the client stays with the IPv6 address from old prefix and doesn't update it. I've used tcpdump to monitor DHCP-related traffic and could not see DHCPv6 RECONFIGURE message sent by dnsmasq to clients on prefix change. I assume that this is the cause of the problem: DHCP clients are not aware of changed prefix and can't act without corresponding notification from server. As dhcp client I use build-in DHCP client from system-networkd, just for info, maybe it matters. If I'm wrong with my assumption I'd appreciate any explanation helping me to configure dnsmasq and DHCP client properly. Best regards, -- Andrey Vakhitov E-Mail: <mailto:and...@vakhitov.net> and...@vakhitov.net Stuttgart, Germany ___ Dnsmasq-discuss mailing list Dnsmasq-discuss@lists.thekelleys.org.uk http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss
