How to monitor HP P410 hardware RAID degraded in Freenas

hphp-prolianthp-smart-arraytruenaszfs

I would like to run freenas on a HP P410 hardware RAID 5 4x600GB 15k SAS array and be alerted in the case of physical disk failure, however the freenas documentation says:

to prevent problems, do not enable the S.M.A.R.T. service if your
disks are controlled by a RAID controller as it is the job of the
controller to monitor S.M.A.R.T. and mark drives as Predictive Failure
when they trip.

As the machine is installed in a lights-out data center, there's no way for the controller to alert anyone of RAID array being degraded. S.M.A.R.T. would appear to be an option – perhaps a physical disk failure would show as a high "Reallocated Sectors Count" at the array level?

Notes: Other options I have considered, but rejected are: Using a dumb HP H220 HBA with RAID-Z (<1.2TB guaranteed) or RAID 10 (1.2TB), but neither provide the capacity of RAID 5 (1.8TB), and I don't have any spare drive bays (HP DL120 G7). Also, there doesn't appear to be an HP agent for BSD.
Context: I have a pair of these servers to reconfigure (main and replicated – 8 disks total) and they provide for an SQLServer and other VMs via iSCSI.

Update: I'm going down the cciss route (here's how I installed cciss on FreeNAS 9.x). Other possibility: RAID controller with out-of-band management on ethernet.

Best Answer

You really can't monitor the array status that well on your platform. One tacky option is cciss_vol_status, but it's far from the mainstream approach.

This is kind of a bad combination of hardware and software. FreeBSD ProLiant support is a bit Meh... Okay, it's actually worse than that...

So a few things to consider:

  • ZFS is a software RAID and volume management solution engineered for use with raw SAS controllers and to bypass any form of hardware RAID.
  • Hardware RAID can be used, but you lose some of the data protection features of ZFS.
  • If you use hardware RAID with ZFS, be sure to do it on an OS/platform that allows you to monitor it!
  • HP Smart Array controllers like the P410 are popular and well-supported under every other operating system out there. They present a block device to the OS comprised of the collection of underlying RAID devices.
  • Smart Array controllers do not have a JBOD or passthrough mode. They are RAID-only.
  • HP has tools and management agents to monitor hardware health and send SNMP and email alerts. Again, these won't work on your FreeNAS.
  • S.M.A.R.T. is not the last word in storage monitoring!

I'd either ditch FreeNAS if you insist on using hardware RAID or use a more ZFS-friendly SAS controller (LSI 9211) or give up the monitoring of the hardware RAID.

Related Topic