Add a test to check ipv6 routes over ipv4 bgp session

[pavel-shirshov]

Description of PR

Summary: Added a new testcase to check ipv6 routes, received over dynamic ipv4 bgp session. This test is required to check sonic-net/sonic-quagga#42

Type of change

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

Approach

What is the motivation for this PR?

Recently we found a bug in sonic-quagga. We need to test sonic after the bug fix sonic-net/sonic-quagga#42.

How did you do it?

I used existing ipv4 bgp speaker test as an example. I added ipv6 test case and also fixed some issues in the common test functions:

• add support of the older sonic release
• generate_ips() wasn't able generage ips for the ipv6 prefixes
• fix bugs in exabgp ansible module. Otherwise I got

    @summary: Class for PTF
        if (res.is_failed or 'exception' in res) and not module_ignore_errors:
>           raise RunAnsibleModuleFail("run module {} failed".format(self.module_name), res)
E           RunAnsibleModuleFail: run module exabgp failed, Ansible Results =>
E           {
E               "changed": false, 
E               "invocation": {
E                   "module_args": {
E                       "local_asn": null, 
E                       "local_ip": null, 
E                       "name": "bgps0", 
E                       "peer_asn": null, 
E                       "peer_ip": null, 
E                       "port": 5000, 
E                       "router_id": null, 
E                       "state": "absent"
E                   }
E               }, 
E               "msg": "Error: (<type 'exceptions.NameError'>, NameError(\"global name 'e' is not defined\",), <traceback object at 0x7f59d6178c20>)"
E           }

common/devices.py:82: RunAnsibleModuleFail

• fib_test.py uses fib.py and lpm.py which didn't work for ipv6

E               "stderr_lines": [
E                   "fib_test.FibTest ... ERROR", 
E                   "", 
E                   "======================================================================", 
E                   "ERROR: fib_test.FibTest", 
E                   "----------------------------------------------------------------------", 
E                   "Traceback (most recent call last):", 
E                   "  File \"ptftests/fib_test.py\", line 353, in runTest", 
E                   "    self.check_ip_ranges(ipv4=False)", 
E                   "  File \"ptftests/fib_test.py\", line 152, in check_ip_ranges", 
E                   "    next_hop = self.fib[ip_range.get_first_ip()]", 
E                   "  File \"ptftests/fib.py\", line 73, in __getitem__", 
E                   "    return self._ipv6_lpm_dict[str(ip)]", 
E                   "  File \"ptftests/lpm.py\", line 77, in __getitem__", 
E                   "    return self._subnet_tree[key]", 
E                   "  File \"/usr/local/lib/python2.7/dist-packages/SubnetTree.py\", line 157, in __getitem__", 
E                   "    return _SubnetTree.SubnetTree___getitem__(self, cidr)", 
E                   "KeyError: '::2'", 
E                   "", 
E                   "----------------------------------------------------------------------", 
E                   "Ran 1 test in 0.009s", 
E                   "", 
E                   "FAILED (errors=1)"
E               ], 
E               "stdout": "", 
E               "stdout_lines": []
E           }

How did you verify/test it?

I used following line:

cd tests
pytest bgp/test_bgp_speaker.py --testbed=vms3-t0-s6100 --inventory=../ansible/str --testbed_file=../ansible/testbed.csv --host-pattern=vms3-t0-s6100 --module-path=../ansible/library --disable_loganalyzer

Result

root@69a3478e5869:~/sonic-mgmt/tests# pytest bgp/test_bgp_speaker.py --testbed=vms3-t0-s6100 --inventory=../ansible/str --testbed_file=../ansible/testbed.csv --host-pattern=vms3-t0-s6100 --module-path=../ansible/library --disable_loganalyzer
============================================= test session starts ==============================================
platform linux2 -- Python 2.7.12, pytest-4.6.9, py-1.8.1, pluggy-0.13.1
ansible: 2.8.7
rootdir: /var/johnar/Networking-acs-sonic-mgmt/tests, inifile: pytest.ini
plugins: ansible-2.2.2
collected 3 items                                                                                              

bgp/test_bgp_speaker.py ...                                                                              [100%]

========================================== 3 passed in 257.53 seconds ==========================================

Any platform specific information?

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

This test support t0 topology.

Documentation

[lgtm-com]

This pull request introduces 1 alert when merging 8b9830c into 009983d - view on LGTM.com

new alerts:

• 1 for Unused local variable

[lgtm-com]

This pull request introduces 1 alert when merging 487b272 into 009983d - view on LGTM.com

new alerts:

• 1 for Unused local variable

[lguohan]

can you check the test cases failure?

[pavel-shirshov]

@lguohan. I have to add ipv6 prefix for loopback in the minigraph generation. I totally forgot. I'll fix tomorrow.

[lgtm-com]

This pull request introduces 1 alert when merging 06d2f22 into 0805536 - view on LGTM.com

new alerts:

• 1 for Unused local variable

[lguohan]

can you check the test failure?

[pavel-shirshov]

@lguohan
The test failure because the test couldn't find ipv6 address on the vlan interface

23:09:11          # Generate ipv6 nexthops
23:09:11  >       vlan_ipv6_entry = mg_facts['minigraph_vlan_interfaces'][1]
23:09:11  E       IndexError: list index out of range

It looks like this PR #1982 is not used in the test.

[lgtm-com]

This pull request introduces 1 alert when merging 91878db into f5d9eaa - view on LGTM.com

new alerts:

• 1 for Unused local variable

[lgtm-com]

This pull request fixes 1 alert when merging b65f811 into 94c9904 - view on LGTM.com

fixed alerts:

• 1 for Unused local variable

[lgtm-com]

This pull request fixes 1 alert when merging 97d24b8 into 9da74ca - view on LGTM.com

fixed alerts:

• 1 for Unused local variable

[pavel-shirshov]

retest this please

[lgtm-com]

This pull request fixes 1 alert when merging 9271bf0 into bf49ff0 - view on LGTM.com

fixed alerts:

• 1 for Unused local variable

[lgtm-com]

This pull request fixes 1 alert when merging 6b6eaeb into 16b4469 - view on LGTM.com

fixed alerts:

• 1 for Unused local variable

[lgtm-com]

This pull request fixes 1 alert when merging 38f08c9 into 16b4469 - view on LGTM.com

fixed alerts:

• 1 for Unused local variable

[pavel-shirshov]

retest this please

[lgtm-com]

This pull request fixes 1 alert when merging 34bbeec into 1e4bccc - view on LGTM.com

fixed alerts:

• 1 for Unused local variable