Increase gRPC Max send msg size on gNMI server end and gnmi_get client end

[Sreevanich16]

MSFT ADO - 38461436

Why I did it

Few commands are failing with ResourceExhausted error because the gNMI server could not send messages larger than 4 MB due to the configured gRPC send message size limit.

root@bjw2-can-4600c-6:/# gnmi_get -xpath_target SHOW -xpath ipv6/route -target_addr 127.0.0.1:50051 -logtostderr -insecure true
== getRequest:
prefix: <
  target: "SHOW"
>
path: <
  elem: <
    name: "ipv6"
  >
  elem: <
    name: "route"
  >
>
encoding: JSON_IETF

F0624 10:15:51.503830 2267008 gnmi_get.go:145] Get failed: rpc error: code = ResourceExhausted desc = grpc: trying to send message larger than max (6785546 vs. 4194304)

How I did it

1. Increased the server-side MaxSendMsgSize limit from 4 MB to 8 MB.
2. Increased the MaxRecvMsgSize on gnmi_get client side as well

How to verify it

1. After increasing the MaxSendMsgSize to 8 MB, the original send error is resolved. However, the gnmi_get client now fails with a receive-side limit error, indicating that it cannot handle messages larger than 4 MB:

root@bjw2-can-4600c-6:/# gnmi_get -xpath_target SHOW -xpath ipv6/route -target_addr 127.0.0.1:50051 -logtostderr -insecure true
== getRequest:
prefix: <
  target: "SHOW"
>
path: <
  elem: <
    name: "ipv6"
  >
  elem: <
    name: "route"
  >
>
encoding: JSON_IETF

F0624 10:21:50.736868 2274766 gnmi_get.go:145] Get failed: rpc error: code = ResourceExhausted desc = grpc: received message larger than max (6785546 vs. 4194304)

2. Error is resolved after Increasing the MaxRecvMsgSize on gnmi_get client end

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

• 201811
• 201911
• 202006
• 202012
• 202106
• 202111

Description for the changelog

Link to config_db schema for YANG module changes

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

[Sreevanich16]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[sharmavijay-ms]

I am not able to understand the usage of JwtToken and prefix.
Also can we check how much change will be required to configure it via config entry.