I've got at least one problem of consistently high CPU on an HP 5412. It works fine while the management interface is unavailable, but i'm unable to login to SSH or the web. It seems to happen at random, and if the cpu goes over ~80% it becomes inaccessible.
I can login via Serial and access the commands, but it's painfully slow to display anything. I've looked at the logs and it's pretty sparse. The only thing i can think of is there is a trunk between this switch and a Cisco UCS. It's giving some PVID mismatch, but looking at the logs it's been that way for over a year, with this CPU issue only occurring in the past few weeks.
I'm really at a loss as to why the CPU would be so high. Normally this switch runs <20%. I've not dealt with networking let alone switches in years, it's been my experience that you just set them and they run.
I guess it boils down to any idea after 1+ years of running a switch would go from 20% CPU average to 80% average. Also why would high CPU knock out the IP management interfaces.
FWIW I've rebooted the switch to no avail, if anything it's made it worse.
I've updated firmware, and fixed the PVID issues. The CPU issue still seems to be present, The difference definitely seems to relate to usage, as the day or so it ran fine was during a weekend. I'm not seeing any egregious port usage, or anything like that. Our Toshiba phones do tend to generate errors, but nothing has really changed recently with them. I've updated HP as well.