[docker-sonic-vs]Added support for Mellanox-SN2700 based SKU for docker-sonic-vs

[dgsudharsan]

Signed-off-by: Sudharsan Dhamal Gopalarathnam sudharsand@nvidia.com

Why I did it

Added support for Mellanox-SN2700 based SKU for docker-sonic-vs and to differentiate platform based on hw-sku rather than on fake_platform in VS.
Currently SAI VS library uses hwsku based SAI profile to differentiate and mock different platform implementations. The same functionality in swss is achieved using a fake_platform env variable.
Using a fake_platform has some drawbacks that the vs container appears to still use a different vendor hw-sku

env
PLATFORM=x86_64-kvm_x86_64-r0
HOSTNAME=dd21a1637723
PWD=/
HOME=/root
TERM=xterm
HWSKU=Force10-S6000
SHLVL=1
fake_platform=mellanox
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
DEBIAN_FRONTEND=noninteractive
_=/usr/bin/env

In order to unify the approach at both swss and vs SAI and to be uniform throughout this PR introduces the approach of using hw-sku to differentiate different platforms. This requires support for Mellanox-SN2700 HWSKU for Mellanox platform which is also addressed by this PR.

root@23c9ba83b0aa:/# show platform summary
/bin/sh: 1: sudo: not found
Platform: x86_64-kvm_x86_64-r0
HwSKU: Mellanox-SN2700
ASIC: vs
ASIC Count: 1
Serial Number: N/A
Model Number: N/A
Hardware Revision: N/A
root@23c9ba83b0aa:/# env
PLATFORM=x86_64-kvm_x86_64-r0
HOSTNAME=23c9ba83b0aa
PWD=/
HOME=/root
TERM=xterm
HWSKU=Mellanox-SN2700
SHLVL=1
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
DEBIAN_FRONTEND=noninteractive
_=/usr/bin/env
root@23c9ba83b0aa:/#

How I did it

Copied relevant platform files. Modified orchagent scripts to infer platform from hwsku.

How to verify it

Run the tests that depend on platform type in vs and ensure they pass using the new approach.

Which release branch to backport (provide reason below if selected)

• 201811
• 201911
• 202006
• 202012
• 202106

Description for the changelog

A picture of a cute animal (not mandatory but encouraged)

[lguohan]

can you explain the motivation for doing this?

[dgsudharsan]

can you explain the motivation for doing this?

To have docker-sonic-vs Mellanox-SN2700 based docker-sonic-vs SKU functional. Currently It is missing few files. Additionally there were some concerns over using fake_platform by @kcudnik
sonic-net/sonic-sairedis#920 (comment)
sonic-net/sonic-sairedis#920 (comment)
Currently there is logic need to mock a specific platform both at swss and SAI vs. In SAI vs it is done based on SKU. Using fake_platform just sets swss env variable and other platform parameters in the vs appears to still show Force10-S6000 which doesn't appear to be in place.
Hence created support for a Mellanox docker-sonic-vs SKU and used it to mock mellanox based platforms

[dgsudharsan]

@lguohan Updated the description. Let me know if this sounds good.