I cannot make any comment nor recommendation because I do not know this network. Is this network a flat, Layer 2-only network? Are the VLANs assigned dynamically or statically?
We are currently on 17.12.4 and 17.12.5 but we are starting to roll out 17.15.4. No comment on the stability of 17.12.4, 17.12.5 nor 17.15.4 because, in our environment, nothing much has changed and my complaints about memory leaks in the control-plane is still present (and unmonitored) regardless what firmware we are using. I have always maintained the opinion that IOS-XE is a buggy software and just about anything will cause a memory leak. The bad news to everyone is this: Everybody and every NMS product knows how to monitor the data-plane memory utilization, however, not everyone (nor every NMS product, including DNAC) knows how to monitor and check the control-plane memory utilization. And this is a warning that many people, including Cisco people, continuously ignore.
NOTE:
Before the end of 2025, an announcement will come out from Cisco in the lines of: Going forward, there will be no more "17.19.X" (and later). Instead, it will be renumbered/renamed into 26.A.B with 26.1.1 scheduled for release in January 2026 (taken from the page of Apple's iOS numbering schema). The "26" means it will be year the version gets released. The "A" will be the train (like 17.12.X) and the "B" will be the release, like 17.12.5. Please do not make the mistake in thinking that 26.X.X will be "better", i. e. quality of the code, than 3.X.X, 16.X.X or 17.X.X -- This is purely a "renumbering" or "relabelling" exercise.
