For anyone using the DHCPv6 client app (be.mygod.dhcpv6client) on a recent version of Android, here's something that might save you some frustration - I learned it the hard way.
In theory, you'd only need the app to run occasionally if your leasetimes are reasonably long, so it's tempting to try and save battery by not exempting it from background restrictions. I figured I'd be clever and rig up a trigger to fire it every day plus whenever I reconnected to the network, which is probably cheaper than running a separate app constantly. And lo and behold, my wifi just couldn't hold a connection anymore.
After a lot of troubleshooting, it turns out that, when the app is killed off by the system, the underlying library removes any addresses it's acquired. On its face, this doesn't seem so bad, as the network should revert to IPv4-only after those addresses are removed. But it gets worse: because you stop receiving IPv6 traffic immediately, but the connectivity check takes a while to invalidate the cached IPv6 address it's monitoring, Android will interpret the fact that it's no longer receiving responses as evidence that the network failed. So your phone disconnects from the wifi - and if the whole cycle triggers on every connection, you'll never get more than about a minute of connectivity before it all comes crashing down.
So as far as I can tell, there's no alternative but to exempt it from background restrictions, and leave it running constantly even though you only need it to exchange a couple packets with the router every 24 hours. If anyone figures out a way to overcome this, I'd love to hear about it. Otherwise, I hope this helps someone else facing similar frustrations.
I'm trying DHCP and DHCPv6 on an Arduino Uno and I'm wondering why it doesn't work ... the script would use 264.3% RAM (5412 bytes / 2048 bytes).
#arduino #dhcp #dhcpv6 #ipv6 #outofmemory
Are there any #Ubiquiti users who made #IPv6 over #PPPoE with #DHCPv6 work (prefix delegation)? I have spent months debugging it while feeding a support ticket that goes nowhere. I can see packets that advertise the network prefix allocated by the ISP but not replies to router solicitations later. In effect, I never end up with an IPv6 on the router (#UDMPro).
Obviously, the ISP's #Huawei router just works...
Did I ever mention my love-hate relationship with Ubiquiti?!
#ubiquiti #ipv6 #pppoe #dhcpv6 #udmpro #huawei
#DHCPv6 #server dhcpy6d 1.4.0 released. See https://dhcpy6d.de/dhcpy6d-1-4-0-released #ipv6
Finding out your client’s duid for dhcp is a really tough task, especially considering all the different client implementations. #dhcpv6
@junicast Could it be that very few things support DHCPv6.. For example Android based devices will only use RA and not DHCPv6.
Can you find the devices you want in the "IPv6 Routing" tab, "IPv6 Neighbours" section on /cgi-bin/luci/admin/status/routes (if using gui). #IPv6 #OpenWRT #DHCPv6
Lorenzo Colitti (main driver of not including #DHCPv6 on #Android) has now proposed a compromise for all big networks who want to use DHCPv6 to assign #IPv6 addresses:
Prefix Delegation with /64 via flag in the PIO:
https://datatracker.ietf.org/meeting/116/materials/slides-116-v6ops-using-dhcp-pd-to-allocate-64-per-host-in-broadcast-networks
Accountability ✅
SLAAC ✅
This looks like a solid compromise to me for huge networks. It does require at least a /48 per site to support 65k devices but additionally solves other issues as well (NDP cache ex. attack)
Android will get a DHCPv6 client.
It's one thing setting up #IPv6 the way you want it, but having #FreeBSD jails on the bridge whose member is egress was another level for me. First, having #DHCPv4, #DHCPv6 and #SLAAC on the same network was somewhat hard to achieve. Then came filtering. The hard part about it is how to drop everything on the host, but not drop packets which flow towards jails. After a while, I learned PF has <self>. And then I learned that fe80::/10 is special, and in what way is it special. The result is current pf.conf template I came up with: https://github.com/cbsd/reggae/blob/master/templates/pf.conf
When all that started working, I wanted my isc-dhcpd and isc-dhcpd6 to register A and AAAA records in nsd. The result of that effort is https://github.com/cbsd/reggae/blob/master/templates/reggae-register.sh and it is far from perfect. I set myself a goal of not using anything outside base OS, so it took a while to handle IPv6 addresses.
If you're asking your self why i did all this, it's because I wanted to learn about dual stack and what are the problems. I am by no means network engineer, only a sys admin who decided to learn more about networking.
#ipv6 #freebsd #DHCPv4 #dhcpv6 #slaac
It's crazy that this feature request has been open for over 10 years now. Will the Android team continue to ignore and neglect of implementing DHCPv6 into Android? Even Windows Vista supports DHCPv6.
New RIOT release online https://github.com/RIOT-OS/RIOT/releases/tag/2021.10. Thanks, Benjamin Valentin for managing! New features include #FIDO2, #RPL over #BLE , GNRC TCP, #DHCPv6 relay agent +++ #IoT #openSource #operatingSystem
#opensource #fido2 #rpl #dhcpv6 #iot #operatingsystem #ble