[yang-models] vlan validation issue

[ganglyu]

Description

'VLAN': {'Vlan1000': {'alias': 'ab1', 'dhcp_servers': ['192.0.0.1', '192.0.0.2'], 'dhcpv6_servers': ['fc02:2000::1', 'fc02:2000::2'], 'mac': '00:aa:bb:cc:dd:ee', 'vlanid': '1000'}, 'Vlan2000': {'alias': 'ab2', 'dhcp_servers': ['192.0.0.1'], 'dhcpv6_servers': ['fc02:2000::3', 'fc02:2000::4'], 'vlanid': '2000'}},

Config db schema generated by minigraph can’t pass yang validation:

• there's no 'mac' field in sonic-vlan yang model.

It seems that we need to update yang model or sonic-config-engine.

Steps to reproduce the issue:

1. Run command 'sonic-cfggen -m tests/simple-sample-graph-case.xml --print-data'.
2. Use sonic_yang to validate config db schema.

Describe the results you received:

Yang validation failed.

Describe the results you expected:

Yang validation should pass.

Output of show version:

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Output of show techsupport:

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Additional information you deem important (e.g. issue happens only occasionally):

[ganglyu]

@theasianpianist https://github.com/Azure/sonic-buildimage/blob/master/src/sonic-config-engine/tests/simple-sample-graph-case.xml#L141 Why do you add 'mac' field? If it's necessary, could you please update sonic-vlan.yang?