Unfortunately, APM settings don’t persist between power cycles so if we wanted to change disk settings with APM they would need to be reapplied on every boot. Advanced power management levels80h and higher do not permit the device to spin down to save power. For example, a device may implement one power management method from 80h to A0h and a higherperformance, higher power consumption method from level A1h to FEh. To prevent parking more often that is useful (for a server, usually that choice would be “very rarely”), there are a couple ways to do it and which apply will depend on what the hard drive vendor’s firmware supports. With the SMART metrics captured by Prometheus, it’s fairly easy to write a query that will show how often a given disk is parking its heads. Since I use Prometheus to capture information on the server’s operation however, I can use that to monitor that my hard drives are doing well.
I set power mode to Idle and advanced power management to the lowest setting (1) which should spin down the disk after 5 mins. Hello,Like many users of Seagate Exos drives, I have found that they park their heads very aggressively, approximately every 2 minutes. AnyDesk allows you to establish remote desktop connections between devices and opens up unprecedented possibilities of collaborating online and administrating your IT network. Its primary purpose is to grant bidirectional remote access between personal computers and mobile devices. To do this, both devices must have the program installed and must allow access through the use of security keys. The current settings for a disk can be queried with the –showEPCSettings flag.
FreeBSD’s sesutil is a tool to interface with the SES devices on your system. You should also configure smartd to monitor your disks and send you alerts, which may give you advanced notice when a drive is starting to fail. These special boards, called SAS Expanders, reduce the total cabling required to provide power and signal pathways to all connected disks.
For chassis with larger numbers of drives, or when connecting external JBOD chassis, it is common for the drives to connect to a specialized board that provides power and routing for the SATA/SAS signals to the controller. When building a storage system, there are many different ways the disks might be connected to the system. NVME-oF allows storage devices and arrays in remote chassis to be connected to local motherboards. NVMe storage comes in many form factors, from small M.2 devices to U.2 and other hot-swappable formats intended for servers. NVMe connects storage devices directly to the PCIe bus, offering extremely low latency and high throughput.
Most Seagate disks have configurable Extended Power Conditions (EPC) settings that include timers for how long the disk needs to stay idle before entering various low-power modes. Disk vendors typically provide their own vendor-specific ways to do persistent configuration of power management settings, so it’s worth trying to use those instead so the desired configuration doesn’t depend on the host system applying it, instead being configured in the drive (but in some cases it might be desirable to have the host configure that!). To prevent parking the heads at all a value greater than 128 may do the job (254 is a common choice, as the highest-power setting available), but it’s possible that some disks won’t behave this way because the ATA specification refers only to spinning down the disk and does not specify anything about parking heads. Typical SAS connectors support up to 4 drives per “lane”, but with an expander up to 255 devices are possible. An eight lane controller can only directly attach to 8 disks, requiring more controllers (consuming additional PCI-E slots) to connect more drives. This has long been the interface bus used by most home users to connect their hard drives, and is supported by nearly every motherboard.
We can also see that the disk in Slot07 was recently swapped, and that Slot08 does not contain a disk and its locate LED is activated. SES provides a mechanism to query information from the enclosure, including temperature, fan speed, and status of power supplies. Many backplanes include support for SCSI Enclosure Services (SES).
This will activate the fault LED for element 9 (Slot 08) on the first SES device. You can avoid any uncertainty by enabling the “locate” or “fault” LED for the drive you mean to replace. This example creates a new GPT partition scheme on da36, creates a 4 GiB swap partition aligned to 1 MiB boundaries, and then adds a ZFS partition with the label e3s01-ZGY0XH87 using the remainder of the space on the disk.
SAS disk reservations provide the ability to connect to the disk redundantly—or even across multiple machines—while ensuring it is only used by one of them at a time. SAS provides many more features than SATA does—including full duplex operations, advanced error recovery, multipath, and disk reservations. It too was an extension on an existing interface bus which offered greatly improved performance. SATA+AHCI improved data transfer speeds, simplicity of communication, and included abilities that we today take for granted, such as “hot swap” and command queueing. These concepts also apply to other operating systems, but the tools might differ slightly.
The timer values specified are in milliseconds, so this example will park the disk heads after 30 minutes of inactivity. If we wanted to allow the disk to still park its heads but at minimum frequency, setting the APM value to 7Fh (hdparm -B 127) seems to be the correct choice. Of the three disks that I decided need some attention, I have one Western Digital disk and two Seagate ones.
My question is – is there a way to tell if a certain disk suffers from the issue prior to purchasing? For the system I’m monitoring here, the SSD that it boots from has a wearout indicator sitting on 95 of 100 (only 5% of the rated life consumed), visibly unchanged for a long time so it’s not very interesting as an example. (The properties like ID_SERIAL_SHORT can be queried on a running system using udevadm info, such as udevadm info /dev/sdd to get the properties of the disk currently assigned ID sdd.) Somewhat more useful for monitoring is the smartmon_load_cycle_count_raw_value, which provides the actual number of load cycles that have been done. Secondly what are your disk monitoring refresh intervals and what do you use on your system to monitor SMART disk health?
The parking rate basically drops to zero at the time I updated the settings for the Seagate drives, and the Western Digital one hasn’t changed because it needs to be powered off to change that setting and I haven’t done so yet. The other slight annoyance when setting the idle3 timer on WD drives is that changes only take effect when the drive is powered on, usually meaning the host computer must be fully shut down and started back up for any changes to be seen- this makes experimentation to determine how raw timer values are interpreted a slower and more tedious process. Of particular note, WD Green drives ship configured to park the heads after only 8 seconds of inactivity which could notionally wear out the disk in a matter of months if the heads are cycling more-or-less continuously! For drives made by Western Digital, the inactivity timer for parking the heads is called the idle3 timer.
In this case, there are at least two disks that I probably need to configure, since /dev/sde seems to be parking as often as about every 4 minutes (0.004 Hz) and /dev/sdc is only parking slightly less often. The smartmon_load_cycle_count_value metric seems like it would be the right one to query, but that actually expresses a percentage value (0-100) representing how many load cycles remain in the specified lifetime- on reaching 0 the disk has done a very large number of load cycles. It does support reading arbitrary metrics from text files written by other programs with its textfile collector however, which is fairly easy to integrate with arbitrary other tools. These communities are filled with knowledgeable individuals who can offer more personalized advice and help you navigate the complexities of long-term data storage.
It is fairly well-known among techies that hard drives reveryplay used in server-like workloads can suffer from poor configuration by default such that they frequently load and unload their heads, which can cause disks to fail much faster than they otherwise would. My Seagate Archive SMR disk (which began life as an external hard drive and was retired from that role when it became too small to hold as much as I wanted to back up to it) apparently doesn’t support reporting EPC settings (since asking for them says so), and initially didn’t accept new values for the idle timers either. The Prometheus Node Exporter is the canonical tool for capturing machine metrics like utilization and hardware information with Prometheus, but it alone does not support probing SMART data from storage drives. While SSDs don’t have any heads to park, most do report a media_wearout_indicator that represents the amount of data written to the device in relation to the amount that it’s specified to accept before the Flash storage medium wears out.
However, I noticed that my HDD’s heads park (particulary Seagate Exos) every 3 minutes. ZFS is widely trusted for large-scale storage, but production environments expose design mistakes,… When dealing with critical data, you only get one chance to do it right. The status field is a bitmask supporting a number of different options, but the main ones we care about are 1 (OK), and 2 (FAULTED). When combined with a JSON parser like jq, this can be used to automate tasks for each disk.