On 2016-03-20 00:39, Florian Gleixner wrote:
On 03/19/2016 08:54 PM, Carlos E. R. wrote:
I just told my router to send log entries to a computer on my lan, and it is talkative:
<3.4> 2016-03-19T20:24:50+01:00 router radvd 675 - - our AdvOtherConfigFlag on br0 doesn't agree with fe80::8cae:84ff:fe43:27d4
You have more than one device, that sends router advertisements or dhcp answers. See man radvd -> AdvOtherConfigFlag on|off
When set, hosts use the administered (stateful) protocol for autoconfiguration of other (non-address) information. The use of this flag is described in RFC 4862.
and i think the flag controls how RFC 4862 section 5.6 is managed.
Ah, it is starting to make sense! Kind of. I do have two routers, yes. One is the actual router, connected to my ISP fibre, the other is only acting as a WiFi access point, not as router (its WAN is disconnected). But the IP that the message is reporting, fe80::8cae:84ff:fe43:27d4, happens to belong to my switch, not the router. ISP--fibre--[Main router]---[switch]---[R-W-A.P.]-- My computer is connected to the switch. On the "Router-WiFi-Access Point" I have dhcp disabled on IPv4. However, it is impossible to disable RADVD, which is used for IPv6, and is the culprit here. The configuration page says (TD-W8970): +++...................... IPv6 LAN Settings The parameters of IPv6 LAN can be configured on this page. Note: Only default group supports IPv6 now. Group: Default Address Autoconfiguration Type: (*) RADVD () DHCPv6 Server Site Prefix Configuration Type: ( ) Delegated (*) Static Site Prefix: fC00:0:0:0:: Site Prefix Length: 64 ......................++- I suppose I should switch it to "delegated". But it does not allow me to, because it wants me to enter a "Prefix delegated WAN connection", and it says "No available interface". If I click "Save", it says "No WAN connection! Please add one first." But there is no WAN, it not connected. The router is configured in Wireless Router Mode. The port that acts as "WAN" is disconnected, there is only one wire coming from the switch to one of its LAN connectors, and another going to TV top box. Ie, I use its switch side. The Wireless works just fine, in the same LAN as the wire side, which is what I want. The WAN configuration is: +++...................... EWAN Settings Connection Type: Static IP Enable IPv4: (*) IP Address: 192.168.2.1 Subnet Mask: 255.255.255.0 Gateway: 0.0.0.0 (optional) DNS Server: 192.168.1.1 (optional) Secondary DNS Server: 0.0.0.0 (optional) Enable IPv6: ( ) Default Gateway: Current connection. ......................++- I will try "Connection Type: Dynamic" with IPv6 enabled. It will be eternally in "connecting state"... However, now it allows me in the "IPv6 LAN Settings" to enable "delegated" settings. However, this does not stop the router from complaining: <3.4> 2016-03-20T13:04:17+01:00 router radvd 675 - - our AdvOtherConfigFlag on br0 doesn't agree with fe80::8cae:84ff:fe43:27d4 And the wifi router also complains:
<1.5> 2016-03-20T13:05:03.743227+01:00 oldrouter - - - DHCPC: Send DISCOVER with request ip 0.0.0.0 and unicast flag 1 <1.5> 2016-03-20T13:05:06.743370+01:00 oldrouter - - - DHCPC: Send DISCOVER with request ip 0.0.0.0 and unicast flag 1 <1.5> 2016-03-20T13:05:09.743202+01:00 oldrouter - - - DHCPC: Send DISCOVER with request ip 0.0.0.0 and unicast flag 1 <1.5> 2016-03-20T13:05:14.743305+01:00 oldrouter - - - DHCPC: Send DISCOVER with request ip 0.0.0.0 and unicast flag 0 <1.4> 2016-03-20T13:05:17.695966+01:00 oldrouter - - - IGMP: V2 igmp router occured! Not matching ours V3. <1.5> 2016-03-20T13:05:17.743162+01:00 oldrouter - - - DHCPC: Send DISCOVER with request ip 0.0.0.0 and unicast flag 0 <1.5> 2016-03-20T13:05:20.743185+01:00 oldrouter - - - DHCPC: Recv no OFFER, DHCP Service unavailable <1.4> 2016-03-20T13:05:32.705996+01:00 oldrouter - - - IGMP: V2 igmp router occured! Not matching ours V3. <1.4> 2016-03-20T13:05:47.717960+01:00 oldrouter - - - IGMP: V2 igmp router occured! Not matching ours V3. <1.4> 2016-03-20T13:06:02.729800+01:00 oldrouter - - - IGMP: V2 igmp router occured! Not matching ours V3. <1.4> 2016-03-20T13:06:17.740839+01:00 oldrouter - - - IGMP: V2 igmp router occured! Not matching ours V3. <1.4> 2016-03-20T13:06:32.753723+01:00 oldrouter - - - IGMP: V2 igmp router occured! Not matching ours V3. <1.4> 2016-03-20T13:06:47.764641+01:00 oldrouter - - - IGMP: V2 igmp router occured! Not matching ours V3. <1.5> 2016-03-20T13:07:01.742983+01:00 oldrouter - - - DHCPC: Send DISCOVER with request ip 0.0.0.0 and unicast flag 0 <1.4> 2016-03-20T13:07:02.774230+01:00 oldrouter - - - IGMP: V2 igmp router occured! Not matching ours V3. <1.5> 2016-03-20T13:07:04.743067+01:00 oldrouter - - - DHCPC: Send DISCOVER with request ip 0.0.0.0 and unicast flag 0 <1.5> 2016-03-20T13:07:07.742966+01:00 oldrouter - - - DHCPC: Send DISCOVER with request ip 0.0.0.0 and unicast flag 0 <1.5> 2016-03-20T13:07:12.742616+01:00 oldrouter - - - DHCPC: Send DISCOVER with request ip 0.0.0.0 and unicast flag 1 <1.5> 2016-03-20T13:07:15.742443+01:00 oldrouter - - - DHCPC: Send DISCOVER with request ip 0.0.0.0 and unicast flag 1
I should set the WAN side to "static" and write some sensible IPv6 config, but I do not know what. +++...................... EWAN Settings Connection Type: Static IP Enable IPv4: (*) IP Address: 192.168.2.1 Subnet Mask: 255.255.255.0 Gateway: 0.0.0.0 (optional) DNS Server: 192.168.1.1 (optional) Secondary DNS Server: 0.0.0.0 (optional) Enable IPv6: (*) IPv6 Address: :: Prefix Length: 64 IPv6 Gateway: :: (optional) IPv6 DNS Server: :: (optional) Secondary IPv6 DNS Server: :: (optional) Default Gateway: Current connection. IPv6 Default Gateway: Current connection. ......................++- Any idea what could I write there as IPv6 address and length?
As a first step, I try to find what machine is that in my LAN. I can ping it:
Telcontar:~ # ping6 -I eth0 "fe80::8cae:84ff:fe43:27d4" PING fe80::8cae:84ff:fe43:27d4(fe80::8cae:84ff:fe43:27d4) from fe80::221:85ff:fe16:2d0b eth0: 56 data bytes 64 bytes from fe80::8cae:84ff:fe43:27d4: icmp_seq=1 ttl=64 time=1.79 ms 64 bytes from fe80::8cae:84ff:fe43:27d4: icmp_seq=2 ttl=64 time=0.501 ms 64 bytes from fe80::8cae:84ff:fe43:27d4: icmp_seq=3 ttl=64 time=0.471 ms 64 bytes from fe80::8cae:84ff:fe43:27d4: icmp_seq=4 ttl=64 time=0.489 ms ^C
Try:
ip neighbour show
Telcontar:~ # ip neighbour show fc00::fa1a:67ff:fe91:f422 dev eth0 lladdr f8:1a:67:91:f4:22 router STALE fe80::8cae:84ff:fe43:27d4 dev eth0 lladdr f8:1a:67:91:f4:22 router DELAY fe80::fa8e:85ff:fe64:78f2 dev eth0 lladdr f8:8e:85:64:78:f2 router STALE 192.168.74.119 dev vmnet8 lladdr 00:0c:29:5f:45:90 STALE 192.168.1.1 dev eth0 lladdr f8:8e:85:64:78:f2 REACHABLE 192.168.1.5 dev eth0 lladdr f8:1a:67:91:f4:22 STALE <==== wifi AP. 192.168.1.15 dev eth0 lladdr 00:03:0d:05:17:fc REACHABLE 192.168.1.2 dev eth0 lladdr 00:01:02:03:04:05 REACHABLE 192.168.1.6 dev eth0 lladdr 14:cc:20:ba:ba:bd DELAY <==== switch Telcontar:~ # The second one is the one.
it should show you the arp cache and the contents of the neighbour table. Matching the MAC adresses may help you find the IPv4, but only if there was IPv4 traffic recently.
I provoked some traffic to refresh some of the entries. -- Cheers / Saludos, Carlos E. R. (from 13.1 x86_64 "Bottle" at Telcontar)