07-10-2025 05:16 AM
Hi all,
I’m running into an issue when trying to configure multispeed interfaces (10/25/50G) via NETCONF on Catalyst 9600 (C9600-LC-40YL4CD / IOS-XE 17.12).
Context:
I need to configure interfaces like FiftyGigE2/0/10 or TwentyFiveGigE1/1/1 via NETCONF (e.g., no switchport, mtu, channel-group, etc.).
These interfaces do not appear in the XML schema of the device (get-config on /native/interface/... doesn’t return them).
When I attempt to create or modify them (using either Cisco-IOS-XE-native or ietf-interfaces), I get errors like:
inconsistent value: Device refused one or more commands /if:interfaces/interface[name='FiftyGigE2/0/10']/type is not configured
In CLI, the exact same configuration works perfectly.
Hypothesis:
Could this be because these ports are multigig/multispeed and require the speed to be fixed in order to instantiate the interface in YANG?
(I tried forcing speed in CLI and disabling auto-negotiation, but it didn’t change NETCONF behavior.)
Or is this a known limitation of Cisco-IOS-XE-native YANG models with multispeed linecards?
Already tried:
Creating the interface via ietf-interfaces with <type>ianaift:ethernetCsmacd</type> → same error.
Preconfiguring in CLI (speed 25000, no negotiation auto, no shutdown), then using NETCONF → still rejected.
Searched for relevant bugs or caveats (found CSCwk61990 on FiftyGigE not visible via NETCONF but not sure it applies).
Question:
How can I configure multispeed interfaces via NETCONF?
Is there a required sequence (e.g., activate ports in CLI first, then use NETCONF)?
Or is a newer IOS-XE version required for full YANG support?
Any alternative approaches (different YANG model)?
Thanks in advance for any insights.
07-10-2025 05:26 AM
Digging into very grey matter in my mind here, but think this is a limitation in XE, as (and i am happy to be wrong here) the get-config does not pull these back because they are considered "virtual" or "dormant" state until they're explicitly configured with a specific speed. The YANG models can't see or manipulate interfaces that haven't been "instantiated" with a fixed speed configuration.
I think (guess here) and read this was better in later versions of XE. In the mean time, you could use CLI for initial speed configuration, then NETCONF after?
07-10-2025 06:48 AM
I went ahead and tried your suggestion: I fixed the speed on one of the multispeed interfaces via CLI (speed 25000, speed nonegotiate, no shutdown).
Unfortunately:
The interface still does not appear in the YANG model when doing a get-config.
Attempts to configure it via NETCONF still return same errors
So even after instantiating the interface with a fixed speed, NETCONF does not seem to have visibility or write access to it.
This makes me wonder:
-> Are these multispeed interfaces simply not configurable via NETCONF at all on IOS-XE 17.12 (even after being initialized)?
-> Or is there a workaround (other than falling back to CLI for those ports)?
I’d really prefer to avoid mixing CLI and NETCONF in my playbooks if possible.
07-10-2025 07:51 AM
Thanks for testing this, i would agree this appears to be a platform limitation and hopefully if you upgradee addressed in later release/version.
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