|
IPv6 global addresses and changing WLAN network
![[nl]](/s/countries/nl.gif) Carmen Sandiego on Thursday, 23 June 2011 14:57:34
I've two WLAN AP's with both a different IPv6 subnet. When I change from one AP to the other on my Kubuntu Linux running laptop, my IPv6 Global address from AP1 stays valid and so is the default IPv6 gateway. After a while I get another Global address from within the second AP's subnet and another default IPv6 gateway for the second subnet. Both have the same metric (1024). IPv6 connectivity is broken now (still seems to take AP1 as preferred route). When I disable wireless on the laptop and reenable it, it flushes all IP addresses/routes and receives new ones and connectivity is restored. Shouldn't this be happening autmaticaly when changing AP?
It's a bit silly to have to disable/enable wireless all the time, so might be a bug?
IPv6 global addresses and changing WLAN network
What settings do you use in your radvd?
I simply tend to bridge access points and LAN btw, as then you just get 1 IP address space and all your connections keep on working (quite important for SSH ;). I never had issues moving my laptop to another network though....
IPv6 global addresses and changing WLAN network
Carmen Sandiego on Thursday, 23 June 2011 15:11:27
my radvd.conf just contains the default :
interface eth0 {
AdvSendAdvert on;
AdvHomeAgentFlag off;
prefix <prefix>::/64 {
AdvOnLink on;
AdvAutonomous on;
AdvRouterAddr off;
};
};
this is on a linux box (ubuntu). The other /64 ipv6 subnet comes from a Fritzbox 7340. I'm using separate Ipv6 subnets for testing and getting experience with routing for it. I know I could make it more simple, but you learn more from situations where it doesn't work as expected like mine now ;-)
IPv6 global addresses and changing WLAN network
That looks fine, though except for AdvSendAdvert those are default options.
You should check what the routing tables, especially the routing tables and neighbor caches look like before and after switching access points. Also check what the lifetimes are on the relevant interfaces.
IPv6 global addresses and changing WLAN network
Carmen Sandiego on Thursday, 23 June 2011 15:51:24
Hmmm looks weird...after a while the first default GW router comes into the state FAILED, the caches are empty and STILL the laptop tries to connect to a remote site with the ipv6 address in the first subnet. This fails and then the connection is made via IPv4. The other IPv6 address is not tried.
The expore timers of the default gateways are over 1000seconds, so would take a while longer to timeout....I'll leave it for the moment to see what happens, so no IPv6 connectivity for a while from this one...
IPv6 global addresses and changing WLAN network
Carmen Sandiego on Friday, 24 June 2011 08:49:05
Well indeed after a long while ipv6 connectivity is restored. Couldn't find out which timer is responsible for it, but I think the main question is more if those timers shouldn't reset when changing network? IPv4 works flawlessly and IPv6 should be better isn't it? ;-) Anyway i might have something interesting to research more in depth, unless you've some more hints ;-)
IPv6 global addresses and changing WLAN network
There are quite a few timer values in radvd.conf that instruct the lifetime of a prefix, you could optionally tweak those a bit
IPv6 global addresses and changing WLAN network
Carmen Sandiego on Saturday, 25 June 2011 14:21:27
Solved the problem! :-)
Apperently the network manager from KDE (Kubuntu) is not working properly. With Gnome/Ubuntu it does work fine when roaming, so instead of using the default network-manager in KDE i changed to WICD for it and WICD allready mentiones in it's configuration to flush ip routes...that sounds logical to me and it works fine now too.
Thanks for your suggestions and help Jeroen.
|
![[ch]](/s/countries/ch.gif)
on Thursday, 23 June 2011 15:00:57
Posting is only allowed when you are