Hi, I wanted to pass on a word of encouragement to people who, like me, bought WD Red WDxxEFAX drives for use in a ZFS or RAID system and now feel at risk. WD encourages you to contact customer support. I did. Good things are ensuing.
As many of us know by now, some WD Red drives in the 2TB-6TB range, WDxxEFAX model, use Device Managed Shingled Magnetic Recording (DMSMR) techniques. WD published a blog post, On WD Red NAS Drives (April 22, 2020) with details. DMSMR has some advantages, but also a big downside for those of us using ZFS file-systems: the intense, random write activity during a “resilver” operation (rebuilding data on a new drive after a failure) has caused drives to fail or to run very slowly in tests, leading my hardware vendor to stop recommending this model.
My file server is now running with four 6TB WD60EFAX drives on a ZFS file system. It has run fine so far. I bought WD Reds because it was a NAS application, and WD represents the WD Red line as being ideal for NAS use. However, I’m very worried about what happens when one of the drives eventually fails.
WD’s blog post says, “If you have purchased a WD Red drive, please call our customer care if you are experiencing performance or any other technical issues. We will have options for you. We are here to help.”
I took them up on it. I called WD customer support, and told them that I was concerned that the WD60EFAX drives might let me down due to the DMSMR technology. I got some pushback at first. Nevertheless, I persisted. In particular, I said that the test results undermined WD’s brand message for the WD Reds. They raise doubt that the drives with DMSMR are not in fact fit for purpose in the case of a ZFS filesystem (or RAID 5 or 6 probably), doing a resilver operation.
After asking to speak to second-level support, and emphasizing the points about “undermining WD Red brand” and “not fit for purpose if ZFS doing resilver”. I asked that WD preemptively replace my WD60EFAX drives with equivalent drives which did not use DMSMR technology. Eventually, I started getting cooperative responses from support. They are currently following through.
So, my experience says that we should take WD up on their statement. If you have WDxxEFAX drives, and have concerns about how suitable they actually are for your NAS workload, do contact customer support. Give WD a chance to make it right. I did, and I think I may well come out of this in a good situation. I hope you will also.
