4 ms·

I wish I could switch my network to all IPv6 and use NAT64/DNS64, but Android, the world's most popular OS, purposefully disables DHCPv6. I am forced to suppo

I wish I could switch my network to all IPv6 and use NAT64/DNS64, but Android, the world's most popular OS, purposefully disables DHCPv6. I am forced to support IPv4/DHCPv4 for the foreseeable future to support these broken devices.

avidiax 10mo ago
Why can't you use stateless autoconfig?
- candiddevmike 10mo ago
  Because I want to control the suffix assigned to devices for firewall rules and monitoring purposes.
  - avidiax 10mo ago
    Seems like the wrong layer unless your network has more than one router/gateway. Use MAC as the key for firewall and monitoring. Then you don't have multiple rules per device.
    - buggjenrmf 10mo ago
      ”You’re holding it wrong”
franklyworks 10mo ago
Android supports SLAAC and has good support transitional tech like xlat464 and DHCP option 108. I have used these on my network and office to move to IPv6-only for Android. What about lack of DHCPv6 prevents you from using IPv6 on Android?
- candiddevmike 10mo ago
  I can't run SLAAC and DHCPv6 at the same time without giving devices multiple addresses, and Android doesn't support DHCPv6, so I'd have to carve out a separate, SLAAC-based, android-only network. And then figure out firewall rules, multicast reflection, etc.
  - justincormack 10mo ago
    Why is giving multiple addresses a problem?
    - candiddevmike 10mo ago
      No control over which source address is used. I'm assigning a lot of clients DHCP reservations so I can use static addresses for monitoring and firewall rules. With multiple addresses on the same network, clients may use their SLAAC address which won't match the firewall rule.
      - db48x 10mo ago
        That still doesn’t really make sense. Why not run SLAAC on one subnet and have a single firewall rule for the whole thing? You’re not running any major servers on an Android phone, so it won’t be anything complex.
        tsimionescu 10mo ago
        SLAAC can only run on a subnet that's larger than /64, which they might not have access to.
        db48x 10mo ago
        Strictly speaking it can and does run on subnets that are exactly /64. Does anyone actually hand out smaller delegations today?
        10mo ago
dmm 10mo ago
Android supports DHCPv6, just not stateful DHCPv6. You can give each device its own /64 or if you really want to track a devices usage you should use an authenticated layer on top of your base network.
throw0101c 10mo ago
> I wish I could switch my network to all IPv6 and use NAT64/DNS64, but Android, the world's most popular OS, purposefully disables DHCPv6. It does not "disable" DHCPv6. It does not support DHCPv6. Android (really Lorenzo Colitti) in/famously WONTFIX adding DHCPv6 client support: * https://issuetracker.google.com/issues/36949085 https://issuetracker.google.com/issues/36949085 Of course after over a decade of denying that Android needs some kind of DHCP in IPv6, it seems that Android may finally be getting some kind of solution: * https://android-developers.googleblog.com/2025/09/simplifying-advanced-networking-with.html https://android-developers.googleblog.com/2025/09/simplifyin... * Via: https://blog.ipspace.net/2025/09/android-dhcpv6-prefix-delegation/ https://blog.ipspace.net/2025/09/android-dhcpv6-prefix-deleg... Hopefully, having admitted (?) the error of their ways with being SLAAC-only they'll also add 'regular' DHCPv6 in addition to DHCPv6-PD.
- denkmoon 10mo ago
  Holy hell the android dhcpv6 situation is deranged. Been following Mr Colitti’s antics for awhile but only just learned of this prefix delegation news. So now I can delegate an entire subnet but can’t just have a regular address. Why oh why can’t we just have a goddamn normal every day dhcpv6 client like every other os on the planet

avidiax 10mo ago

Why can't you use stateless autoconfig?

candiddevmike 10mo ago
Because I want to control the suffix assigned to devices for firewall rules and monitoring purposes.
- avidiax 10mo ago
  Seems like the wrong layer unless your network has more than one router/gateway. Use MAC as the key for firewall and monitoring. Then you don't have multiple rules per device.
  - buggjenrmf 10mo ago
    ”You’re holding it wrong”

franklyworks 10mo ago

Android supports SLAAC and has good support transitional tech like xlat464 and DHCP option 108. I have used these on my network and office to move to IPv6-only for Android. What about lack of DHCPv6 prevents you from using IPv6 on Android?

candiddevmike 10mo ago
I can't run SLAAC and DHCPv6 at the same time without giving devices multiple addresses, and Android doesn't support DHCPv6, so I'd have to carve out a separate, SLAAC-based, android-only network. And then figure out firewall rules, multicast reflection, etc.
- justincormack 10mo ago
  Why is giving multiple addresses a problem?
  - candiddevmike 10mo ago
    No control over which source address is used. I'm assigning a lot of clients DHCP reservations so I can use static addresses for monitoring and firewall rules. With multiple addresses on the same network, clients may use their SLAAC address which won't match the firewall rule.
    - db48x 10mo ago
      That still doesn’t really make sense. Why not run SLAAC on one subnet and have a single firewall rule for the whole thing? You’re not running any major servers on an Android phone, so it won’t be anything complex.
      - tsimionescu 10mo ago
        SLAAC can only run on a subnet that's larger than /64, which they might not have access to.
        db48x 10mo ago
        Strictly speaking it can and does run on subnets that are exactly /64. Does anyone actually hand out smaller delegations today?
        10mo ago

dmm 10mo ago

Android supports DHCPv6, just not stateful DHCPv6. You can give each device its own /64 or if you really want to track a devices usage you should use an authenticated layer on top of your base network.

throw0101c 10mo ago

> I wish I could switch my network to all IPv6 and use NAT64/DNS64, but Android, the world's most popular OS, purposefully disables DHCPv6. It does not "disable" DHCPv6. It does not support DHCPv6. Android (really Lorenzo Colitti) in/famously WONTFIX adding DHCPv6 client support: * https://issuetracker.google.com/issues/36949085 https://issuetracker.google.com/issues/36949085 Of course after over a decade of denying that Android needs some kind of DHCP in IPv6, it seems that Android may finally be getting some kind of solution: * https://android-developers.googleblog.com/2025/09/simplifying-advanced-networking-with.html https://android-developers.googleblog.com/2025/09/simplifyin... * Via: https://blog.ipspace.net/2025/09/android-dhcpv6-prefix-delegation/ https://blog.ipspace.net/2025/09/android-dhcpv6-prefix-deleg... Hopefully, having admitted (?) the error of their ways with being SLAAC-only they'll also add 'regular' DHCPv6 in addition to DHCPv6-PD.

denkmoon 10mo ago
Holy hell the android dhcpv6 situation is deranged. Been following Mr Colitti’s antics for awhile but only just learned of this prefix delegation news. So now I can delegate an entire subnet but can’t just have a regular address. Why oh why can’t we just have a goddamn normal every day dhcpv6 client like every other os on the planet