[Draft] server: do not allocate nic on public network for NSX VPC VR

[weizhouapache]

Description

The VPC VR for NSX has a public interface/IP allocated, which is not needed as the VPC VR only provides Dhcp/Dns/UserData services.

Types of changes

• Breaking change (fix or feature that would cause existing functionality to change)
• New feature (non-breaking change which adds functionality)
• Bug fix (non-breaking change which fixes an issue)
• Enhancement (improves an existing feature and functionality)
• Cleanup (Code refactoring and cleanup, that may add test cases)
• build/CI
• test (unit or integration test code)

Feature/Enhancement Scale or Bug Severity

Feature/Enhancement Scale

• Major
• Minor

Bug Severity

• BLOCKER
• Critical
• Major
• Minor
• Trivial

Screenshots (if appropriate):

How Has This Been Tested?

How did you try to break this feature and the system with this change?

[codecov]

Codecov Report

❌ Patch coverage is 12.50000% with 7 lines in your changes missing coverage. Please review.
✅ Project coverage is 16.03%. Comparing base (e57a82a) to head (02f193c).
⚠️ Report is 541 commits behind head on 4.20.

Files with missing lines	Patch %	Lines
...ain/java/com/cloud/network/vpc/VpcManagerImpl.java	0.00%	7 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##               4.20   #10081      +/-   ##
============================================
- Coverage     16.03%   16.03%   -0.01%     
  Complexity    12814    12814              
============================================
  Files          5637     5637              
  Lines        493506   493513       +7     
  Branches      59831    59835       +4     
============================================
+ Hits          79129    79130       +1     
- Misses       405601   405607       +6     
  Partials       8776     8776              

Flag	Coverage Δ
uitests	4.02% <ø> (ø)
unittests	16.87% <12.50%> (-0.01%)	⬇️

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[DaanHoogland]

how about StaticNat (and maybe others)?

[weizhouapache]

good question
To be honest, I never tested the case that SourceNat and StaticNat are provided by different providers (e.g. Nsx for Source NAT and VPCVirtualRouter for Static NAT). I do not think it will work.

this PR is aligned with the 4.19 code

cloudstack/server/src/main/java/com/cloud/network/vpc/VpcManagerImpl.java

Lines 3115 to 3119 in f9b1767

	@Override
	public boolean isSrcNatIpRequired(long vpcOfferingId) {
	final Map<Network.Service, Set<Network.Provider>> vpcOffSvcProvidersMap = getVpcOffSvcProvidersMap(vpcOfferingId);
	return vpcOffSvcProvidersMap.get(Network.Service.SourceNat).contains(Network.Provider.VPCVirtualRouter);
	}

[DaanHoogland]

ok, might work. As you create a method isSrcNatIpRequiredForVpcVr the contents seems appropriate, but its use is more like needsPublicInterface does it? and in that case we would also want to test if the VR needs to provide StaticNat. I think a Gateway could be on a static ip as well, in theory at least.

maybe rename the method?

[weizhouapache]

for isolated networks (NATTED mode by default), it uses VR as SourceNat
for Routed networks, it uses VR as Gateway
in both cases, the VR needs a public IP (as Source NAT or Gateway)

For Static NAT, I think we do not need to add a public interface to the VR when VR is created.
when Static NAT is enabled, it may add a public interface if needed

[weizhouapache]

cc
@nvazquez @Pearl1594 @alexandremattioli

[weizhouapache]

as discussed offline, we need to evaluate the impact of the changes and test heavily.
moved to draft, we will revisit in the future