[test_fgnhg] Add test to validate FG ECMP packet flow when neighbors are not resolved

[anish-n]

Description of PR

Summary:
Test case enhancement for newly added capability in Fine Grained ECMP to handle packet flow upon no ECMP next-hops being neighbor resolved.

Type of change

• Bug fix
• Testbed and Framework(new/improvement)
• Test case(new/improvement)

Back port request

• 201911

Approach

What is the motivation for this PR?

Test case enhancement for newly added capability in Fine Grained ECMP to handle packet flow upon no ECMP next-hops being neighbor resolved

How did you do it?

The test will start off with no neighbors resolved and then send packets to the Fine Grained ECMP destination, we will validate that the packets did make it to the endpoint, and validate that the neighbor entry ended up getting resolved via the normal packet flow.

How did you verify/test it?

Ran the pytest with PTF

Any platform specific information?

Supported testbed topology if it's a new test case?

Documentation

[lgtm-com]

This pull request introduces 12 alerts when merging 8cfd77b into e50cc71 - view on LGTM.com

new alerts:

• 9 for Unused local variable
• 2 for Testing equality to None
• 1 for Unreachable code

[yozhao101]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[anish-n]

/azp run

[azure-pipelines]

Commenter does not have sufficient privileges for PR 4225 in repo Azure/sonic-mgmt

[prsunny]

/azp run

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Azure Pipelines successfully started running 1 pipeline(s).

[anish-n]

/azpw run

[prsunny]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[bingwang-ms]

@anish-n We are seeing errors in fg_ecmp_test.py possibly caused by typo
"======================================================================", "ERROR: fg_ecmp_test.FgEcmpTest", "----------------------------------------------------------------------", "Traceback (most recent call last):", " File \"ptftests/fg_ecmp_test.py\", line 549, in runTest", " self.fg_ecmp()", " File \"ptftests/fg_ecmp_test.py\", line 277, in fg_ecmp", " src_ip = str(base_ip + i)", "NameError: global name 'base_ip' is not defined", "", "----------------------------------------------------------------------", "Ran 1 test in 3.008s", "", "FAILED (errors=1)"
Can you help take a look? Thanks

[anish-n]

@anish-n We are seeing errors in fg_ecmp_test.py possibly caused by typo "======================================================================", "ERROR: fg_ecmp_test.FgEcmpTest", "----------------------------------------------------------------------", "Traceback (most recent call last):", " File \"ptftests/fg_ecmp_test.py\", line 549, in runTest", " self.fg_ecmp()", " File \"ptftests/fg_ecmp_test.py\", line 277, in fg_ecmp", " src_ip = str(base_ip + i)", "NameError: global name 'base_ip' is not defined", "", "----------------------------------------------------------------------", "Ran 1 test in 3.008s", "", "FAILED (errors=1)" Can you help take a look? Thanks

Thanks for letting me know @bingwang-ms, will fix it today and send a PR.