FQDN Support for gRPC Subscriptions gRPC telemetry subscriptions are configuration-based, which means that users must specify the receiving host and other subscription parameters as part of the device configuration. This receiver configuration is used to determine the connection details for sending telemetry updates. With the introduction of the FQDN Support for gRPC Subscriptions feature, along with IP addresses, Fully Qualified Domain Names (FQDNs) can also be used for gRPC subscriptions. This feature cannot be disabled. To use FQDN, a subscription must use a named receiver, as described earlier. This example shows an FQDN used for gRPC subscriptions.
telemetry receiver protocol my-receiver host name receiver.cisco.com 12345 protocol grpc-tcp telemetry ietf subscription 101 encoding encode-kvgpb filter xpath /mdt-oper-v2-data/mdt-subscriptions stream yang-push update-policy periodic 1000 receiver name my-receiver telemetry ietf subscription 102 encoding encode-kvgpb filter xpath /mdt-oper-v2-data/mdt-connections stream yang-push update-policy periodic 1000 receiver name my-receiver Displaying On-Change Subscription Capabilities From Cisco IOS XE 17.6.1, Cisco IOS XE software supports the capabilities model, Cisco-IOS-XE-mdt-capabilities-oper.yang that can be queried to determine the paths that support on-change subscriptions and their transports.
This model is patterned after the IETF models, ietf-system-capabilities and ietf-notification-capabilities , which are described in RFC 9196 . Within a single YANG model, some nodes may support on-change, while others may not. Because of this reason, capabilities cannot be specified at the model level. Instead of listing every individual leaf and container node that supports on-change, the Cisco-IOS-XE-mdt-capabilities-oper.yang model essentially lists only the inflection points, that is, the paths to the nodes whose support differs from that of their parent node. This makes the capabilities model very compact. The model has two nodes. • System-level capabilities:
At the top of the model are the system-level capabilities that are similar to the system default; if no matching entry is found in the path of interest, the capabilities are given by the system-level container. The system-level capabilities for Cisco IOS XE support only periodic subscriptions; on-change subscriptions are not supported. • mdt-datastore: The model specifies capabilities on a per-datastore basis, through the mdt-datastore list. Currently, only the running datastore is supported. Model-Driven Telemetry FQDN Support for gRPC Subscriptions Model-Driven Telemetry 29