On 02/16/2017 02:03 AM, James Hogarth wrote:> On 16 February 2017 at 09:09, Alice Wonder <alice at domblogger.net> wrote: >> On 02/16/2017 12:54 AM, Tony Mountifield wrote: >>> >>> In article <4cbb9dc4-f063-3434-b7a1-d4d0e6581b5e at domblogger.net>, >>> Alice Wonder <alice at domblogger.net> wrote: >>>> >>>> https://forum.linode.com/viewtopic.php?f=19&t=14570&p=72785 >>>> >>>> I can not figure out what I need to do. >>>> >>>> Apparently according to linode support, the VM is trying to grab an IPv6 >>>> address with some privacy stuff enabled by default causing it to not >>>> grab the IPv6 address that is assigned to me. >>> >>> >>> Does the accepted answer at the following link give you any useful hints? >>> >>> >>> http://superuser.com/questions/243669/how-to-avoid-exposing-my-mac-address-when-using-ipv6 >>> >>> Cheers >>> Tony >>> >> >> Not really - I tried >> >> net.ipv6.conf.all.use_tempaddr = 0 >> >> and it still fails to grab the proper IPv6 >> >> -=- >> >> Just in case, I did ask Linode support to verify that my hardware address is >> what it is suppose to be. Still waiting to hear on that. >> >> _______________________________________________ > > > it still is key=value ... it uses the ifcfg- files (via the rh > plugin) and they are all key=value > > It would be helpful if you could paste the journal output (journalctl > -u NetworkManager) from the time period of attempting to get an > address ... > > also the nmcli conn sh <connection_name> information for the interface > along with your ifcfg- filesifcfg-lo is the only one that exists on any of the servers - including the VMs that grab the correct IPv6 address. from /sbin/ifconfig -a : eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 178.79.185.217 netmask 255.255.255.0 broadcast 178.79.185.255 inet6 fe80::a8ad:d312:4ef4:7272 prefixlen 64 scopeid 0x20<link> inet6 2a01:7e00::825f:e564:ad53:72fc prefixlen 64 scopeid 0x0<global> ether f2:3c:91:18:8a:7e txqueuelen 1000 (Ethernet) RX packets 9903 bytes 1088621 (1.0 MiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 7786 bytes 1087223 (1.0 MiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 That hardware address - the 18:8a:7e corresponds with what the IPv6 address is suppose to be. But that's not the address it is grabbing, despite the fact that net.ipv6.conf.all.use_tempaddr = 0 is set. I'm seriously wondering if the real issue is a mis-configured dhcp server in their London facility because nothing makes sense. journalctl -u NetworkManager reports no journal entries found. I think the problem must be on their end. It all was working fine until they migrated the VM because of a hardware issue, and I suspect now all the hardware address privacy stuff being the issue is barking up the wrong tree because all the reading I have done seems to indicate that with net.ipv6.conf.all.use_tempaddr = 0 that a fake temporary hardware address would not be sent to their dhcp server when obtaining the address, but the real one, that should be fetching my assigned address. It's all very frustrating but I suspect now the problem isn't the CentOS network configuration. Five other servers all configured the same (started from same CentOS 7 image and network stuff left alone) work properly - so I don't know.
On 16 February 2017 at 10:17, Alice Wonder <alice at domblogger.net> wrote:> On 02/16/2017 02:03 AM, James Hogarth wrote: >> >> On 16 February 2017 at 09:09, Alice Wonder <alice at domblogger.net> wrote: >>> >>> On 02/16/2017 12:54 AM, Tony Mountifield wrote: >>>> >>>> >>>> In article <4cbb9dc4-f063-3434-b7a1-d4d0e6581b5e at domblogger.net>, >>>> Alice Wonder <alice at domblogger.net> wrote: >>>>> >>>>> >>>>> https://forum.linode.com/viewtopic.php?f=19&t=14570&p=72785 >>>>> >>>>> I can not figure out what I need to do. >>>>> >>>>> Apparently according to linode support, the VM is trying to grab an >>>>> IPv6 >>>>> address with some privacy stuff enabled by default causing it to not >>>>> grab the IPv6 address that is assigned to me. >>>> >>>> >>>> >>>> Does the accepted answer at the following link give you any useful >>>> hints? >>>> >>>> >>>> >>>> http://superuser.com/questions/243669/how-to-avoid-exposing-my-mac-address-when-using-ipv6 >>>> >>>> Cheers >>>> Tony >>>> >>> >>> Not really - I tried >>> >>> net.ipv6.conf.all.use_tempaddr = 0 >>> >>> and it still fails to grab the proper IPv6 >>> >>> -=- >>> >>> Just in case, I did ask Linode support to verify that my hardware address >>> is >>> what it is suppose to be. Still waiting to hear on that. >>> >>> _______________________________________________ >> >> >> >> it still is key=value ... it uses the ifcfg- files (via the rh >> plugin) and they are all key=value >> >> It would be helpful if you could paste the journal output (journalctl >> -u NetworkManager) from the time period of attempting to get an >> address ... >> >> also the nmcli conn sh <connection_name> information for the interface >> along with your ifcfg- files > > > ifcfg-lo is the only one that exists on any of the servers - including the > VMs that grab the correct IPv6 address. > > from /sbin/ifconfig -a : >For a start stop using ifconfig ... it's broken at this point on linux, especially on multi ip and ipv6 scenarios Use `ip -6 addr sh` for ipv6 specfic stuff, or just ip addr sh to see all IP address stuff regardless of family> eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 > inet 178.79.185.217 netmask 255.255.255.0 broadcast 178.79.185.255 > inet6 fe80::a8ad:d312:4ef4:7272 prefixlen 64 scopeid 0x20<link> > inet6 2a01:7e00::825f:e564:ad53:72fc prefixlen 64 scopeid > 0x0<global> > ether f2:3c:91:18:8a:7e txqueuelen 1000 (Ethernet) > RX packets 9903 bytes 1088621 (1.0 MiB) > RX errors 0 dropped 0 overruns 0 frame 0 > TX packets 7786 bytes 1087223 (1.0 MiB) > TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 > > That hardware address - the 18:8a:7e corresponds with what the IPv6 address > is suppose to be. But that's not the address it is grabbing, despite the > fact that net.ipv6.conf.all.use_tempaddr = 0 is set. > > I'm seriously wondering if the real issue is a mis-configured dhcp server in > their London facility because nothing makes sense. > > journalctl -u NetworkManager > > reports no journal entries found. >So are you not using NetworkManager then? there should be some logs ...> I think the problem must be on their end. > > It all was working fine until they migrated the VM because of a hardware > issue, and I suspect now all the hardware address privacy stuff being the > issue is barking up the wrong tree because all the reading I have done seems > to indicate that with > > net.ipv6.conf.all.use_tempaddr = 0 > > that a fake temporary hardware address would not be sent to their dhcp > server when obtaining the address, but the real one, that should be fetching > my assigned address.Only if the kernel is doing SLAAC ... if other things (eg NM) are handling it directly they may act differently ... but then from the lack of logs is NM actually handling this? Does systemctl status NetworkManager show it running and does nmcli show anything?> > It's all very frustrating but I suspect now the problem isn't the CentOS > network configuration. >Sounds likely ... depending on what there RA's say and how dhcpv6 is being handled there (if at all) it could drastically affect things - particularly if MAC changed on migration.> Five other servers all configured the same (started from same CentOS 7 image > and network stuff left alone) work properly - so I don't know. >
Having used Linode and CentOS for years I have never had a problem quite like this. Sure sounds like the IPv6 is misconfigured in the DHCP server or is in use somewhere. Some things I would try are: 1. Set "Auto configure networking" in your config profile and reboot. 2. Try to assign the adddress static. 3. Ask Linode to assign you a new IPv6 4. Wait for Linode to fix the problem. Mike
On 02/16/2017 02:32 AM, James Hogarth wrote:> On 16 February 2017 at 10:17, Alice Wonder <alice at domblogger.net> wrote: >> On 02/16/2017 02:03 AM, James Hogarth wrote: >>> >>> On 16 February 2017 at 09:09, Alice Wonder <alice at domblogger.net> wrote: >>>> >>>> On 02/16/2017 12:54 AM, Tony Mountifield wrote: >>>>> >>>>> >>>>> In article <4cbb9dc4-f063-3434-b7a1-d4d0e6581b5e at domblogger.net>, >>>>> Alice Wonder <alice at domblogger.net> wrote: >>>>>> >>>>>> >>>>>> https://forum.linode.com/viewtopic.php?f=19&t=14570&p=72785 >>>>>> >>>>>> I can not figure out what I need to do. >>>>>> >>>>>> Apparently according to linode support, the VM is trying to grab an >>>>>> IPv6 >>>>>> address with some privacy stuff enabled by default causing it to not >>>>>> grab the IPv6 address that is assigned to me. >>>>> >>>>> >>>>> >>>>> Does the accepted answer at the following link give you any useful >>>>> hints? >>>>> >>>>> >>>>> >>>>> http://superuser.com/questions/243669/how-to-avoid-exposing-my-mac-address-when-using-ipv6 >>>>> >>>>> Cheers >>>>> Tony >>>>> >>>> >>>> Not really - I tried >>>> >>>> net.ipv6.conf.all.use_tempaddr = 0 >>>> >>>> and it still fails to grab the proper IPv6 >>>> >>>> -=- >>>> >>>> Just in case, I did ask Linode support to verify that my hardware address >>>> is >>>> what it is suppose to be. Still waiting to hear on that. >>>> >>>> _______________________________________________ >>> >>> >>> >>> it still is key=value ... it uses the ifcfg- files (via the rh >>> plugin) and they are all key=value >>> >>> It would be helpful if you could paste the journal output (journalctl >>> -u NetworkManager) from the time period of attempting to get an >>> address ... >>> >>> also the nmcli conn sh <connection_name> information for the interface >>> along with your ifcfg- files >> >> >> ifcfg-lo is the only one that exists on any of the servers - including the >> VMs that grab the correct IPv6 address. >> >> from /sbin/ifconfig -a : >> > > For a start stop using ifconfig ... it's broken at this point on > linux, especially on multi ip and ipv6 scenarios > > Use `ip -6 addr sh` for ipv6 specfic stuff, or just ip addr sh to see > all IP address stuff regardless of family > >> eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 >> inet 178.79.185.217 netmask 255.255.255.0 broadcast 178.79.185.255 >> inet6 fe80::a8ad:d312:4ef4:7272 prefixlen 64 scopeid 0x20<link> >> inet6 2a01:7e00::825f:e564:ad53:72fc prefixlen 64 scopeid >> 0x0<global> >> ether f2:3c:91:18:8a:7e txqueuelen 1000 (Ethernet) >> RX packets 9903 bytes 1088621 (1.0 MiB) >> RX errors 0 dropped 0 overruns 0 frame 0 >> TX packets 7786 bytes 1087223 (1.0 MiB) >> TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 >> >> That hardware address - the 18:8a:7e corresponds with what the IPv6 address >> is suppose to be. But that's not the address it is grabbing, despite the >> fact that net.ipv6.conf.all.use_tempaddr = 0 is set. >> >> I'm seriously wondering if the real issue is a mis-configured dhcp server in >> their London facility because nothing makes sense. >> >> journalctl -u NetworkManager >> >> reports no journal entries found. >> > > So are you not using NetworkManager then? there should be some logs ... > > >> I think the problem must be on their end. >> >> It all was working fine until they migrated the VM because of a hardware >> issue, and I suspect now all the hardware address privacy stuff being the >> issue is barking up the wrong tree because all the reading I have done seems >> to indicate that with >> >> net.ipv6.conf.all.use_tempaddr = 0 >> >> that a fake temporary hardware address would not be sent to their dhcp >> server when obtaining the address, but the real one, that should be fetching >> my assigned address. > > Only if the kernel is doing SLAAC ... if other things (eg NM) are > handling it directly they may act differently ... but then from the > lack of logs is NM actually handling this? > > Does systemctl status NetworkManager show it running and does nmcli > show anything? >systemctl status NetworkManager ? NetworkManager.service - Network Manager Loaded: loaded (/usr/lib/systemd/system/NetworkManager.service; enabled; vendor preset: enabled) Active: active (running) since Thu 2017-02-16 08:19:34 UTC; 2h 19min ago * more stuff * nmcli eth0: connected to Wired connection 1 "Red Hat Virtio network device" ethernet (virtio_net), F2:3C:91:18:8A:7E, hw, mtu 1500 ip4 default, ip6 default inet4 178.79.185.217/24 route4 178.79.187.246/32 inet6 2a01:7e00::825f:e564:ad53:72fc/64 inet6 fe80::a8ad:d312:4ef4:7272/64 route6 2a01:7e00::/64 * more stuff for other interfaces * -=- The output of sysctl -a | grep net.ipv6 : https://librelamp.com/sysctl.txt It looks from that like it should not be hiding the real MAC address.> >> >> It's all very frustrating but I suspect now the problem isn't the CentOS >> network configuration. >> > > Sounds likely ... depending on what there RA's say and how dhcpv6 is > being handled there (if at all) it could drastically affect things - > particularly if MAC changed on migration. > >> Five other servers all configured the same (started from same CentOS 7 image >> and network stuff left alone) work properly - so I don't know. >> > _______________________________________________ > CentOS mailing list > CentOS at centos.org > https://lists.centos.org/mailman/listinfo/centos >