They seem to follow the anti-corruption layer model for most of their offerings, so I would expect they use what ever OS is best supported by the upstream.

It is a large reason they can mitigate vendor risk IMHO, offering different tiers of switches as an example without being held hostage by on particular switch IC vendor like many brands.

I do wish someone would take up comstar though, netapp bought and killed several jbod lines etc… to kill it before Oracle bought Sun and also killed it to protect their enterprise storage offerings.

NVMe-oF may be a possibility because there are FPGA IP vendors but without comstar there are some challenges IMHO.