Public bug reported: $ openstack subnet show 48c8407b-7ef3-4047-82dd-ca6d671c2162 -c ipv6_address_mode -c ipv6_ra_mode +-------------------+------------------+ | Field | Value | +-------------------+------------------+ | ipv6_address_mode | dhcpv6-stateless | | ipv6_ra_mode | dhcpv6-stateless | +-------------------+------------------+
File: openstack/latest/network_data.json ---------------------------------------- { "services": [ { "type": "dns", "address": "fd12:3456:789a:1::1" } ], "networks": [ { "network_id": "cf79eea0-6196-45a0-b9f8-ff9dd95eaab3", "type": "ipv6_dhcpv6-stateless", "services": [ { "type": "dns", "address": "fd12:3456:789a:1::1" } ], "netmask": "ffff:ffff:ffff:ffff::", "link": "tap5910c6cc-2d", "routes": [ { "netmask": "::", "network": "::", "gateway": "fd12:3456:789a:1::fffe" } ], "ip_address": "fd12:3456:789a:1:f816:3eff:fee2:3aa3", "id": "network0" } ], "links": [ { "vif_id": "5910c6cc-2d6e-4a44-bf05-2accdefd0316", "type": "phy", "ethernet_mac_address": "fa:16:3e:73:0d:96", "id": "tap5910c6cc-2d", "mtu": 1450 } ] } Actual result ------------- The network config forces the client to try dhcpv6, not stateless e.g slaac. This fails when there is no DHCPv6 configured, or DHCPv6 is only configured to provide advanced options such a bootfile-url etc. # Created by cloud-init on instance boot automatically, do not edit. # BOOTPROTO=none DEFROUTE=yes DEVICE=eth0 DHCPV6C=yes HWADDR=fa:16:3e:73:0d:96 IPV6INIT=yes IPV6_DEFAULTGW=fd12:3456:789a:1::fffe MTU=1450 ONBOOT=yes TYPE=Ethernet USERCTL=no Expected result --------------- The configuration written should differentiate between dhcp6-stateful and dhcp6-stateless. For dhcp6-stateless "DHCPV6C=yes" should be replaced by IPV6_AUTOCONF=yes as shown in the example below. # Created by cloud-init on instance boot automatically, do not edit. # BOOTPROTO=none DEFROUTE=yes DEVICE=eth0 IPV6_AUTOCONF=yes HWADDR=fa:16:3e:73:0d:96 IPV6INIT=yes IPV6_DEFAULTGW=fd12:3456:789a:1::fffe MTU=1450 ONBOOT=yes TYPE=Ethernet USERCTL=no The issue starts is in the following code[1]: if 'dhcp' in network['type']: t = 'dhcp6' if network['type'].startswith('ipv6') else 'dhcp4' subnet.update({ 'type': t, }) This makes the assumption that 'ipv6_dhcpv6-stateless' and 'ipv6_dhcpv6-stateful' can be treated the same. Then in the code[2] the subnet type is checked and DHCPV6C is always used. if subnet_type == 'dhcp6': # TODO need to set BOOTPROTO to dhcp6 on SUSE iface_cfg['IPV6INIT'] = True iface_cfg['DHCPV6C'] = True Grepping the source code it looks like this is only affecting cloudinit/net/sysconfig.py. [1] https://git.launchpad.net/cloud-init/tree/cloudinit/sources/helpers/openstack.py#n587 [2] https://git.launchpad.net/cloud-init/tree/cloudinit/net/sysconfig.py#n346 ** Affects: cloud-init Importance: Undecided Status: New ** Tags: rhel -- You received this bug notification because you are a member of Yahoo! Engineering Team, which is subscribed to cloud-init. https://bugs.launchpad.net/bugs/1847517 Title: cloudinit/net/sysconfig.py writed incorrect config for dhcp-stateless openstack subnets Status in cloud-init: New Bug description: $ openstack subnet show 48c8407b-7ef3-4047-82dd-ca6d671c2162 -c ipv6_address_mode -c ipv6_ra_mode +-------------------+------------------+ | Field | Value | +-------------------+------------------+ | ipv6_address_mode | dhcpv6-stateless | | ipv6_ra_mode | dhcpv6-stateless | +-------------------+------------------+ File: openstack/latest/network_data.json ---------------------------------------- { "services": [ { "type": "dns", "address": "fd12:3456:789a:1::1" } ], "networks": [ { "network_id": "cf79eea0-6196-45a0-b9f8-ff9dd95eaab3", "type": "ipv6_dhcpv6-stateless", "services": [ { "type": "dns", "address": "fd12:3456:789a:1::1" } ], "netmask": "ffff:ffff:ffff:ffff::", "link": "tap5910c6cc-2d", "routes": [ { "netmask": "::", "network": "::", "gateway": "fd12:3456:789a:1::fffe" } ], "ip_address": "fd12:3456:789a:1:f816:3eff:fee2:3aa3", "id": "network0" } ], "links": [ { "vif_id": "5910c6cc-2d6e-4a44-bf05-2accdefd0316", "type": "phy", "ethernet_mac_address": "fa:16:3e:73:0d:96", "id": "tap5910c6cc-2d", "mtu": 1450 } ] } Actual result ------------- The network config forces the client to try dhcpv6, not stateless e.g slaac. This fails when there is no DHCPv6 configured, or DHCPv6 is only configured to provide advanced options such a bootfile-url etc. # Created by cloud-init on instance boot automatically, do not edit. # BOOTPROTO=none DEFROUTE=yes DEVICE=eth0 DHCPV6C=yes HWADDR=fa:16:3e:73:0d:96 IPV6INIT=yes IPV6_DEFAULTGW=fd12:3456:789a:1::fffe MTU=1450 ONBOOT=yes TYPE=Ethernet USERCTL=no Expected result --------------- The configuration written should differentiate between dhcp6-stateful and dhcp6-stateless. For dhcp6-stateless "DHCPV6C=yes" should be replaced by IPV6_AUTOCONF=yes as shown in the example below. # Created by cloud-init on instance boot automatically, do not edit. # BOOTPROTO=none DEFROUTE=yes DEVICE=eth0 IPV6_AUTOCONF=yes HWADDR=fa:16:3e:73:0d:96 IPV6INIT=yes IPV6_DEFAULTGW=fd12:3456:789a:1::fffe MTU=1450 ONBOOT=yes TYPE=Ethernet USERCTL=no The issue starts is in the following code[1]: if 'dhcp' in network['type']: t = 'dhcp6' if network['type'].startswith('ipv6') else 'dhcp4' subnet.update({ 'type': t, }) This makes the assumption that 'ipv6_dhcpv6-stateless' and 'ipv6_dhcpv6-stateful' can be treated the same. Then in the code[2] the subnet type is checked and DHCPV6C is always used. if subnet_type == 'dhcp6': # TODO need to set BOOTPROTO to dhcp6 on SUSE iface_cfg['IPV6INIT'] = True iface_cfg['DHCPV6C'] = True Grepping the source code it looks like this is only affecting cloudinit/net/sysconfig.py. [1] https://git.launchpad.net/cloud-init/tree/cloudinit/sources/helpers/openstack.py#n587 [2] https://git.launchpad.net/cloud-init/tree/cloudinit/net/sysconfig.py#n346 To manage notifications about this bug go to: https://bugs.launchpad.net/cloud-init/+bug/1847517/+subscriptions -- Mailing list: https://launchpad.net/~yahoo-eng-team Post to : yahoo-eng-team@lists.launchpad.net Unsubscribe : https://launchpad.net/~yahoo-eng-team More help : https://help.launchpad.net/ListHelp