<html><body><div style="color:#000; background-color:#fff; font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:12pt"><div>Hi folks,</div><div><br></div><div style="background-color: transparent;">I am working on nova-network in Havana. I have a very unique use case where I need to add duplicate VLANs in nova-network. I am trying to add multiple networks in nova-network with same VLAN ID. The reason is as follows:</div><div style="background-color: transparent;"><br></div><div style="background-color: transparent;">The cluster that I have has an L3 backplane. We have been given a limitation that, per rack, we have a few networks with unique VLAN tags, and the VLAN tags repeat in every rack. So now, when I add networks in nova-network, I need to add these networks in same VLAN. </div><div style="background-color: transparent;"><br></div><div style="background-color: transparent;">nova-network currently has
a unique constraint on ("vlan", "deleted"). So to allow for duplicate VLANs in the DB, I am removing that unique constraint. I am modifying the migrate scripts to make sure that UC doesn't apply again on db_sync. I am also modifying the unit tests to reverse their sense (make sure that duplicate VLANs are allowed)</div><div style="background-color: transparent;"><br></div><div style="background-color: transparent;">After making these changes, I have verified following scenarios:</div><div style="background-color: transparent;">1. Add networks with duplicate VLANs</div><div style="background-color: transparent;">2. Update networks with duplicate VLANs</div><div style="background-color: transparent;">3. db_sync doesn't revert back the constraint.</div><div style="background-color: transparent;">4. VM comes up properly and I can ping it. </div><div style="background-color: transparent;"><br></div><div style="background-color:
transparent;">Since this is a DB schema change, I am a bit skeptical about it, and hence, looking for expert advice.</div><div style="background-color: transparent;"><br></div><div style="background-color: transparent;">1. How risky is it to make DB schema change?</div><div style="background-color: transparent;">2. I know that I have to look out for any new migration scripts that touch that UC/Index. Anything else that I need to worry about w.r.t migration scripts?</div><div style="background-color: transparent;">3. Any more scenarios I should be testing?</div><div style="background-color: transparent;"><br></div><div style="background-color: transparent;">Thank you in advance!</div><div><br></div></div></body></html>