Hello David.

Forgot one "A". So it is SLAAC a scheme where IP address of the host in IPv6 is generated from the mac address by the host itself and so it is stateless at that sense and does not require keeping IP to MAC database anywhere. Also unless privacy extension is enabled the machine will get the same IP address always if it keeps the same MAC.

Routing prefix in this case comes from either DHCP or from the router using router solicitation - but all of that are not required to keep any MAC databases either.

BTW there are also IPv6 link-local addresses that are autogenerated the same way but does not require any routeing prefixes as they work over the local network only. Those can also be used for the slaves if we sure they are in the same LAN. The good point is that they do not require any intermediates for anything and typical pattern for DNS is using mDNS that does not require centralized DNS servers either since it is LAN only.

Some patterns for IPv6 deployment use both global and link-local addresses together.

https://en.wikipedia.org/wiki/IPv6_address#Stateless_address_autoconfiguration

Anton.


On Fri, May 13, 2016 at 12:55 PM, dcaro@redhat com <dcaro@redhat.com> wrote:
On 05/13 10:50, Anton Marchukov wrote:
> Hello All.
>
> Then I suggest consider rolling out IPv6 for the slaves right away
> especially since it was declared a goal for oVirt 4. This can also simplify
> slaves management as we can use SLAC for IP assignment and can solve that
> DHCP update problems we had in foreman due to stale mac addresses etc.. the
> mac will be coming directly from oVirt mac pools and then SLAC will setup
> an IP and we can autoregister in DNS.


What is SLAC?

>
> Anton.
>
> On Fri, May 13, 2016 at 10:37 AM, dcaro@redhat com <dcaro@redhat.com> wrote:
>
> > On 05/13 09:10, Anton Marchukov wrote:
> > > Hello All.
> > >
> > > Are those IPs are used by any tests or the jobs itself?
> >
> > Are used by the slaves themselves (each slave has one ip), not really
> > needed
> > for anything (the slaves are not contacted by any outside machine nor
> > offering
> > any service)
> >
> > >
> > > Anton.
> > >
> > > On Fri, May 13, 2016 at 9:03 AM, David Caro Estevez <dcaroest@redhat.com
> > >
> > > wrote:
> > >
> > > > One possibility that will give us a lot of ips is using internal ones,
> > > > though it will require a bit more configuration but now that the
> > jenkins
> > > > master is in phx I think it might be a good option
> > > >
> > > > David Caro
> > > > El 13 may. 2016 7:57, Eyal Edri <eedri@redhat.com> escribió:
> > > >
> > > > Please open a ticket in jira on extending the ip range,  i guess we
> > need
> > > > to handle ir soon
> > > > On May 12, 2016 8:58 PM, "Nadav Goldin" <ngoldin@redhat.com> wrote:
> > > >
> > > >> sure, added 4 more FC23 slaves, and on the way hit the IPs limit,
> > > >> had to remove some old unused testing VMs to release IPs.
> > > >> we have some useless leases there such as an IP for each template,
> > > >> though I'm not 100% sure if its safe to simply delete them from
> > foreman
> > > >> (they are saved as templates in the engine, so theoretically shouldn't
> > > >> be a problem)
> > > >>
> > > >>
> > > >>
> > > >>
> > > >> On Thu, May 12, 2016 at 4:53 PM, David Caro <dcaro@redhat.com> wrote:
> > > >>
> > > >>> On 05/12 16:50, Nadav Goldin wrote:
> > > >>> > ok I'll add also FC23, though I think the problem is the vdsm jobs,
> > > >>> not sure
> > > >>> > why they use only fc* instead of the el7 ones
> > > >>>
> > > >>> Thanks man, that's because (at least the check-merged) use libvirt to
> > > >>> start up
> > > >>> vms, and trying to use libvirt from a fc23 chroot on an el7 host
> > ends up
> > > >>> in
> > > >>> error, so they have to run on fc23/21 slaves
> > > >>>
> > > >>> >
> > > >>> > On Thu, May 12, 2016 at 4:33 PM, David Caro <dcaro@redhat.com>
> > wrote:
> > > >>> >
> > > >>> > > On 05/12 12:46, Nadav Goldin wrote:
> > > >>> > > > Hi, I added few more el7 slaves, there is a (relatively) new
> > > >>> template
> > > >>> > > > 'centos72-jenkins-slave' in the Jenkins_CentOS cluster.
> > > >>> > > > iirc there was a discussion few months ago about our IPs
> > limit, I
> > > >>> think
> > > >>> > > > we're approaching that(there are
> > > >>> > > > 102 fixed addresses in foreman.phx.ovirt.org dhcpd server, and
> > > >>> this is
> > > >>> > > > without the old ovirt-srv* which are not managed there)
> > > >>> > >
> > > >>> > > Actually, we are scarce on fc23 slaves, not el (right now we
> > have 28
> > > >>> idle
> > > >>> > > el7
> > > >>> > > slaves, and I've been waiting for more than 45min for a lago
> > > >>> check-patch to
> > > >>> > > start on a fc23 slave)
> > > >>> > >
> > > >>> > > >
> > > >>> > > >
> > > >>> > > > On Tue, May 10, 2016 at 7:04 PM, David Caro <dcaro@redhat.com>
> > > >>> wrote:
> > > >>> > > >
> > > >>> > > > > On 05/10 18:02, David Caro wrote:
> > > >>> > > > > > On 05/10 18:53, Eyal Edri wrote:
> > > >>> > > > > > > Looking at the load on our hypervisors I'm sure we can
> > add
> > > >>> more
> > > >>> > > slaves
> > > >>> > > > > to
> > > >>> > > > > > > jenkins.
> > > >>> > > > > > > Is there a documented procedure on how to add a new
> > slave so
> > > >>> > > anyone in
> > > >>> > > > > the
> > > >>> > > > > > > team can do it?
> > > >>> > > > > > >
> > > >>> > > > > >
> > > >>> > > > > > I remember writing something about the templates and such,
> > > >>> will look
> > > >>> > > for
> > > >>> > > > > it.
> > > >>> > > > > >
> > > >>> > > > > > Though it might be a bit old, not sure if we have changed
> > > >>> anything in
> > > >>> > > > > the last
> > > >>> > > > > > months, maybe someone has newer info.
> > > >>> > > > >
> > > >>> > > > >
> > > >>> > > > > There's some docs here:
> > > >>> > > > >
> > > >>> > > > >
> > > >>> > > > >
> > > >>> > >
> > > >>>
> > http://ovirt-infra-docs.readthedocs.io/en/latest/Phoenix_Lab/oVirt_Hosts.html#ovirt-datacenter-organization
> > > >>> > > > >
> > > >>> > > > > >
> > > >>> > > > > > >
> > > >>> > > > > > >
> > > >>> > > > > > >
> > > >>> > > > > > >
> > > >>> > > > > > > --
> > > >>> > > > > > > Eyal Edri
> > > >>> > > > > > > Associate Manager
> > > >>> > > > > > > RHEV DevOps
> > > >>> > > > > > > EMEA ENG Virtualization R&D
> > > >>> > > > > > > Red Hat Israel
> > > >>> > > > > > >
> > > >>> > > > > > > phone: +972-9-7692018
> > > >>> > > > > > > irc: eedri (on #tlv #rhev-dev #rhev-integ)
> > > >>> > > > > >
> > > >>> > > > > > > _______________________________________________
> > > >>> > > > > > > Infra mailing list
> > > >>> > > > > > > Infra@ovirt.org
> > > >>> > > > > > > http://lists.ovirt.org/mailman/listinfo/infra
> > > >>> > > > > >
> > > >>> > > > > >
> > > >>> > > > > > --
> > > >>> > > > > > David Caro
> > > >>> > > > > >
> > > >>> > > > > > Red Hat S.L.
> > > >>> > > > > > Continuous Integration Engineer - EMEA ENG Virtualization
> > R&D
> > > >>> > > > > >
> > > >>> > > > > > Tel.: +420 532 294 605
> > > >>> > > > > > Email: dcaro@redhat.com
> > > >>> > > > > > IRC: dcaro|dcaroest@{freenode|oftc|redhat}
> > > >>> > > > > > Web: www.redhat.com
> > > >>> > > > > > RHT Global #: 82-62605
> > > >>> > > > >
> > > >>> > > > >
> > > >>> > > > >
> > > >>> > > > > > _______________________________________________
> > > >>> > > > > > Infra mailing list
> > > >>> > > > > > Infra@ovirt.org
> > > >>> > > > > > http://lists.ovirt.org/mailman/listinfo/infra
> > > >>> > > > >
> > > >>> > > > >
> > > >>> > > > > --
> > > >>> > > > > David Caro
> > > >>> > > > >
> > > >>> > > > > Red Hat S.L.
> > > >>> > > > > Continuous Integration Engineer - EMEA ENG Virtualization R&D
> > > >>> > > > >
> > > >>> > > > > Tel.: +420 532 294 605
> > > >>> > > > > Email: dcaro@redhat.com
> > > >>> > > > > IRC: dcaro|dcaroest@{freenode|oftc|redhat}
> > > >>> > > > > Web: www.redhat.com
> > > >>> > > > > RHT Global #: 82-62605
> > > >>> > > > >
> > > >>> > > > > _______________________________________________
> > > >>> > > > > Infra mailing list
> > > >>> > > > > Infra@ovirt.org
> > > >>> > > > > http://lists.ovirt.org/mailman/listinfo/infra
> > > >>> > > > >
> > > >>> > > > >
> > > >>> > >
> > > >>> > > > _______________________________________________
> > > >>> > > > Infra mailing list
> > > >>> > > > Infra@ovirt.org
> > > >>> > > > http://lists.ovirt.org/mailman/listinfo/infra
> > > >>> > >
> > > >>> > >
> > > >>> > > --
> > > >>> > > David Caro
> > > >>> > >
> > > >>> > > Red Hat S.L.
> > > >>> > > Continuous Integration Engineer - EMEA ENG Virtualization R&D
> > > >>> > >
> > > >>> > > Tel.: +420 532 294 605
> > > >>> > > Email: dcaro@redhat.com
> > > >>> > > IRC: dcaro|dcaroest@{freenode|oftc|redhat}
> > > >>> > > Web: www.redhat.com
> > > >>> > > RHT Global #: 82-62605
> > > >>> > >
> > > >>>
> > > >>> --
> > > >>> David Caro
> > > >>>
> > > >>> Red Hat S.L.
> > > >>> Continuous Integration Engineer - EMEA ENG Virtualization R&D
> > > >>>
> > > >>> Tel.: +420 532 294 605
> > > >>> Email: dcaro@redhat.com
> > > >>> IRC: dcaro|dcaroest@{freenode|oftc|redhat}
> > > >>> Web: www.redhat.com
> > > >>> RHT Global #: 82-62605
> > > >>>
> > > >>
> > > >>
> > > > _______________________________________________
> > > > Infra mailing list
> > > > Infra@ovirt.org
> > > > http://lists.ovirt.org/mailman/listinfo/infra
> > > >
> > > >
> > >
> > >
> > > --
> > > Anton Marchukov
> > > Senior Software Engineer - RHEV CI - Red Hat
> >
> > --
> > David Caro
> >
> > Red Hat S.L.
> > Continuous Integration Engineer - EMEA ENG Virtualization R&D
> >
> > Tel.: +420 532 294 605
> > Email: dcaro@redhat.com
> > IRC: dcaro|dcaroest@{freenode|oftc|redhat}
> > Web: www.redhat.com
> > RHT Global #: 82-62605
> >
>
>
>
> --
> Anton Marchukov
> Senior Software Engineer - RHEV CI - Red Hat

--
David Caro

Red Hat S.L.
Continuous Integration Engineer - EMEA ENG Virtualization R&D

Tel.: +420 532 294 605
Email: dcaro@redhat.com
IRC: dcaro|dcaroest@{freenode|oftc|redhat}
Web: www.redhat.com
RHT Global #: 82-62605



--
Anton Marchukov
Senior Software Engineer - RHEV CI - Red Hat