Guessing this might be a firewall issue? A customer of mine reported this issue, and I've been able to recreate it. Attempted to restart gRPC on the device (remove gRPC config and re-add it), but the issue persists. Here's a sample gnmi get (with the gnmic tool) that was successful prior to the introduction of this issue:
gnmic -a sandbox-iosxr-1.cisco.com:57777 -u admin -p C1sco12345 --insecure get --path openconfig:/interfaces
Error message:
target "sandbox-iosxr-1.cisco.com:57777" get request failed: failed to create a gRPC client for target "sandbox-iosxr-1.cisco.com:57777" : sandbox-iosxr-1.cisco.com:57777: context deadline exceeded
"Context deadline exceeded" means that the request was not handled by the server within the timeout period for the gRPC client - so perhaps we have some type of connectivity issue between FW and device (note that TCP 57777 *does* respond to telnet) or the the XRv9K needs to be restarted due to a bug of some sort.
