Comment 6 for bug 1172808

Hi Phil,

Sorry, maybe I didn't explain myself properly. What I mean is that I feel that is wrong to create a port early in the process just to avoid a potential error down the line. It needlessly leak implementation details all the way to the API. Creating just a port is something that makes sense in Quantum, but with nova-network still lying around, moving the operation higher up in the stack may cause some serious refactoring (if I understand it correctly, the operation takes place when allocating the network). That said, I 100% agree with you that potential errors conditions should be checked before hopping on the compute node. That's where Quota validation comes in: quota levels should be checked at the very beginning, and that's when you can respond meaningfully to users who do not meet their requirements. The problem you have is a manifestation of the fact that port quota is not checked at all, unlike other quotas like core, ram etc. To me, addressing the above-mentioned issue by creating the port early enough does not feel like the right solution, but that's my personal opinion.

I wasn't proposing to centralize quota management into Nova, and by all means I was not advocating for (yet another) -aaS project. Adding another potential bootleneck/dependency for all the other projects does not sound very wise to me, and having Nova pulling quotas from other projects (since it already initiates the communication with them) seemed like a reasonable first approach than not checking quota levels at all, and thus risking to run into the very issue you ran into.

Thanks,
Armando