1. What is the problem
Currently dhcp port handle is only done in the Nova_apigw. Please
refer to our design documnet[1] to see why dhcp port needs special
process, which is discussed in section 7.4.10. Since we are going
to support one top network to spread into different AZs(availability
zones), routers will be created in different AZs. For shared VLAN
type network, bottom networks in different AZs are actually in the
same broadcast domain, so router gateway IPs should be different
in different AZs, otherwise we have two interfaces with the same
IP in the same broadcase domain. Thus, we need to allocate one IP
for each bottom router and the Tricircle plugin needs to handle
dhcp port creation.
2. What is the solution to the problem
Reconstrut the code to move dhcp port handle from the Nova_apigw
to the helper module, so both the Nova_apigw and the Tricircle
plugin can use.
3. What the features need to be implemented to the Tricircle
to realize the solution
No new feature introuduced.
[1] https://docs.google.com/document/d/18kZZ1snMOCD9IQvUKI5NVDzSASpw-QKj7l2zNqMEd3g
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