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<p><font size="2" face="sans-serif">The allow_overlapping_ips configuration option in it's current form was mainly used to cover older distros that did not support namespaces as you have mentioned. That's why in its current form this option operates across all networks of all tenants. That is, if the option is set to false, overlapping IPs are not allowed even across tenants.</font><br>
<font size="2" face="sans-serif">If the option is to be redefined/reimplemented/interpreted as allowing or disallowing overlapping IPs within the scope of a single tenant, then I think that would be useful to some.</font><br>
<br>
<font size="2" face="sans-serif">Mohammad</font><br>
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<img width="16" height="16" src="cid:1__=0ABBF480DFF3DAB08f9e8a93df938@us.ibm.com" border="0" alt="Inactive hide details for Carl Baldwin ---03/25/2015 11:37:50 AM---Yesterday, I got looking at another option that I had comple"><font size="2" color="#424282" face="sans-serif">Carl Baldwin ---03/25/2015 11:37:50 AM---Yesterday, I got looking at another option that I had completely forgotten about. It is "allow_over</font><br>
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<font size="1" color="#5F5F5F" face="sans-serif">From: </font><font size="1" face="sans-serif">Carl Baldwin <carl@ecbaldwin.net></font><br>
<font size="1" color="#5F5F5F" face="sans-serif">To: </font><font size="1" face="sans-serif">"OpenStack Development Mailing List (not for usage questions)" <openstack-dev@lists.openstack.org></font><br>
<font size="1" color="#5F5F5F" face="sans-serif">Date: </font><font size="1" face="sans-serif">03/25/2015 11:37 AM</font><br>
<font size="1" color="#5F5F5F" face="sans-serif">Subject: </font><font size="1" face="sans-serif">[openstack-dev] [Openstack-operators] [Neutron] allow_overlapping_ips (was: Deprecating the use_namespaces option ...)</font><br>
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<tt><font size="2">Yesterday, I got looking at another option that I had completely<br>
forgotten about. It is "allow_overlapping_ips", set in neutron.conf<br>
and defaults to False. It appears that when it is False, Neutron<br>
doesn't allow any overlapping IPs throughout the deployment, across<br>
all networks. My guess is that the vast majority of deployments will<br>
set this to True as a matter of course.<br>
<br>
My suspicion is that this option is related to the use_namespaces<br>
option because if namespaces are not used, then isolating routing<br>
domains would not be possible on the network node. However, there may<br>
be other reasons for needing this option.<br>
<br>
I'm not yet proposing this option be deprecated. I'm asking for<br>
feedback from operators and others who might be using the default<br>
value of False.<br>
<br>
Carl<br>
<br>
On Tue, Mar 24, 2015 at 1:21 PM, Assaf Muller <amuller@redhat.com> wrote:<br>
> Note that </font></tt><tt><font size="2"><a href="https://review.openstack.org/#/c/166888/">https://review.openstack.org/#/c/166888/</a></font></tt><tt><font size="2"> has been merged.<br>
> This means that the option has been deprecated for K and will be<br>
> removed in L. Anyone using the non-default value of False will be looking<br>
> at errors in his logs.<br>
><br>
> ----- Original Message -----<br>
>><br>
>><br>
>> On 3/23/2015 3:56 AM, Miguel Ángel Ajo wrote:<br>
>> > I see you point Van,<br>
>> ><br>
>> > In the other hand, removing it, cleans up lot of conditional code parts<br>
>> > (moving parts at the other side),<br>
>> > and also the non-netns case is not tested by upstream CI, AFAIK, so it<br>
>> > could be broken anytime<br>
>> > and we would not notice it.<br>
>> ><br>
>> ><br>
>> ><br>
>> > Miguel Ángel Ajo<br>
>> ><br>
>> > On Monday, 23 de March de 2015 at 9:25, Van Leeuwen, Robert wrote:<br>
>> ><br>
>> >>> I think there are valid reasons to not use namespaces:<br>
>> >>><br>
>> >>> * Fewer moving parts == less can potentialy fail<br>
>> >>> * Troubleshooting is easier due to less places to look / need no<br>
>> >>> familiarity with namespaces & tools<br>
>> >>> * If I remember correctly setting up a namespace can get really<br>
>> >>> slow when you have a lot of them on a single machine<br>
>> >>><br>
>> >><br>
>> >> > IMHO, those shouldn’t be valid reasons anymore, since they were due<br>
>> >> > iproute, or sudo issues<br>
>> >> > that have been corrected long ago, and all distros installing neutron<br>
>> >> > are supporting netns at this<br>
>> >><br>
>> >> Well, you exactly made my point:<br>
>> >> There is lots that can and will go wrong with more moving parts.<br>
>> >> That they are fixed at the moment does not mean that there will not be<br>
>> >> a new bug in the future…<br>
>> >><br>
>> >> Cheers,<br>
>> >> Robert van Leeuwen<br>
>> >> _______________________________________________<br>
>> >> OpenStack-operators mailing list<br>
>> >> OpenStack-operators@lists.openstack.org<br>
>> >> <</font></tt><tt><font size="2"><a href="mailto:OpenStack-operators@lists.openstack.org">mailto:OpenStack-operators@lists.openstack.org</a></font></tt><tt><font size="2">><br>
>> >> </font></tt><tt><font size="2"><a href="http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-operators">http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-operators</a></font></tt><tt><font size="2"><br>
>> ><br>
>> ><br>
>> ><br>
>> > __________________________________________________________________________<br>
>> > OpenStack Development Mailing List (not for usage questions)<br>
>> > Unsubscribe: OpenStack-dev-request@lists.openstack.org?subject:unsubscribe<br>
>> > </font></tt><tt><font size="2"><a href="http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev">http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev</a></font></tt><tt><font size="2"><br>
>> ><br>
>><br>
>> FWIW we were doing CI without namespaces before Kilo simply due to RHEL<br>
>> 6.5 not having the support w/o a kernel patch.<br>
>><br>
>> Since Kilo dropped py26 support we moved to RHEL 7* for py27 and that<br>
>> has namespace support so it's no longer an issue for us.<br>
>><br>
>> --<br>
>><br>
>> Thanks,<br>
>><br>
>> Matt Riedemann<br>
>><br>
>><br>
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