Get gRPC Max msg size from env variables by Sreevanich16 · Pull Request #228 · Azure/sonic-gnmi.msft

Sreevanich16 · 2026-07-07T05:20:25Z

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 default 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

Default max send/receive msg size is hardcoded as 4 MB. Added the logic of reading the value from env variables which can be added in Deamon set configuration.

How to verify it

Steps followed for testing - these params are needed to be added as env variables

1. docker exec -it telemetry bash
2. supervisorctl stop telemetry
3. export gRPC_MAX_SEND_MSG_SIZE=8388608
4. export gRPC_MAX_RECEIVE_MSG_SIZE=8388608
5. supervisorctl start telemetry

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)

Error is resolved after Increasing the MaxRecvMsgSize on gnmi_get client end

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

Description for the changelog

Link to config_db schema for YANG module changes