Array Best Practices & backing up

Something to think about – we had a couple of models from the same batch die within a day of each other recently, and while that may be coincidence there may also have been something about that batch that made them die under certain usage conditions or at a certain age. Now, if they had been a mirrored pair the mirror would have been lost and we’d have had to go to a backup to restore the data. Fortunately we had spread that batch out across several arrays so the failures didn’t result in any downtime and the drives have been RMA’d as per usual.   If you’re buying several drives at once this is something to keep in mind – try to source them from different batches if possible or spread the drives out so that if they do all fail in a short space you won’t lose anything. We certainly don’t keep our backups on the same media as our main arrays just in case something catastrophic happens to a batch of disks.   A good rule of thumb for valuable data is 3, 2, 1: 3 copies, 2 types of media, 1 offsite. If your data is important – family photos, important documents, anything that would be hard to replace or irreplaceable – remember to back it up. Even a drive or thumbdrive at a family member or friend’s house could save you if your home or work gets burgled.

Adding another disk to a ZFS mirror

I was asked how to add a disk into a ZFS mirror today; this is an easy one:   # zpool attach [poolname] [existing disk] [new disk]   …and done! The pool will begin to resilver with the new disk as part of the existing mirror. You might want to do this to replace a part of the mirror which has been removed or is faulty, or you might want to expand a 2-way mirror to a 3-way mirror (longer MTBF forĀ  the 3-way, beyond that it’s not worth it).

BIOS update: Asus P8B WS

Asus have updated the bios of this workstation board to support Ivy Bridge CPUs; please note that you’ll need a Sandy Bridge CPU installed to do this update so please make sure if you are upgrading that you do so before installing a new CPU.   You can find the update (#2009) here.

SAS Cable Length for Norco 4224+M1015

  This is a question we get asked reasonably often – what is the right SAS cable length for a Norco 4220/4224 chassis while using IBM M1015 HBAs?   50cm: Doable but puts a great deal of strain on the connectors, particularly on the card end. 60cm: Enough with some slack and no excessive pressure on the connectors. 75cm: Enough with a reasonable amount of slack; will likely require a few cable ties to prevent obstructing airflow if you have more than one. 1m: Too much slack.   We tested the lengths with the HBAs in each of the available slots, from nearest to the CPU to farthest away. Were you to have raid cards/HBAs with end ports rather than upwardly-facing ports you would be able to get away with the 50cm cables without issue.

ECC in Intel Network Cards

Intel have released some information about ECC in their networking cards;   Some of the older chips like the 82571 – found in cards like the Pro/1000 PT single/dual/quad port NICs – actually do have error correction on the in-band traffic, which is good news. You can see that the latest generation (i.e. i-350, i-540 etc.) have ECC on both the in-band and out-of-band (management) traffic – that’s on top of benefits like lower TDP and CPU consumption.   Of note is that the more common chips for onboard Intel Gigabit LAN ports – e.g. 82574L – doesn’t feature ECC or parity at all on either in-band or out-of-band traffic. For those who are trying to create the most stable, secure system possible this is a consideration which may prompt you to look at some of the newer network cards which do have those features. I would think that for the majority of users it’s unlikely to have a significant impact on your data long-term but if you’re buying new, it pays to have all the facts. Also, for those of us who are paranoid about data corruption, well, there’s now one more place you can have ECC for your peace of mind…   Source.

HD6450 – Review for servers/non-3D workstations

The AMD Radeon HD 6450 is a low-end graphics card that’s perfectly suited to basic graphics duties such as you’ll need on a server or workstation board that lacks inbuilt graphics capabilities (on-CPU or a discrete chip). It’s flexible in output – VGA, HDMI and DVI – is more than powerful enough for everyday use or even production 2D Photoshop work – is silent thanks to the passive cooling design and only draws somewhere between ~6-9W on idle and ~27W under load. For systems which are generally headless you should probably be looking at a server board which incorporates onboard graphics, but if you have a setup which requires a graphics card that will go largely unused the low idle power draw is quite appealing here. It does require a x16 physical slot but works fine in slots which are lesser electrically, e.g. x8 or below.   The card doesn’t run particularly hot at idle so the passive cooling system should fit in with most setups without causing significant additional heat load to nearby components.   It’s also worth a look-in if you have hit the maximum number of monitors your current setup requires and don’t plan on gaming or doing 3D work on the additional monitor – no point in spending up big on a noisy gaming card for that purpose. At around AU$40 this card represents good value for someone who doesn’t need a great deal of graphics performance but wants to minimise the noise and power consumption of their system, and it’s our current go-to card for this sort of requirement.