Pool degraded with very few usage

TrueNAS General
,
42

How can I know if a disk to buy is CMR or SMR. In Amazon i never see these description.

Here end the smart long test of ada3 but… this Ada3 is not the seagate that is remove… so… is usefull

st login: Mon Oct  7 22:33:11 2024 from 192.168.1.86
FreeBSD 13.1-RELEASE-p7 n245428-4dfb91682c1 TRUENAS

        TrueNAS (c) 2009-2023, iXsystems, Inc.
        All rights reserved.
        TrueNAS code is released under the modified BSD license with some
        files copyrighted by (c) iXsystems, Inc.

        For more information, documentation, help or support, go here:
        http://truenas.com
Welcome to TrueNAS

Warning: the supported mechanisms for making configuration changes
are the TrueNAS WebUI and API exclusively. ALL OTHERS ARE
NOT SUPPORTED AND WILL RESULT IN UNDEFINED BEHAVIOR AND MAY
RESULT IN SYSTEM FAILURE.

root@NAS3[~]# smartctl -a /dev/ada3
smartctl 7.2 2021-09-14 r5236 [FreeBSD 13.1-RELEASE-p7 amd64] (local build)
Copyright (C) 2002-20, Bruce Allen, Christian Franke, www.smartmontools.org

=== START OF INFORMATION SECTION ===
Model Family:     Western Digital Red
Device Model:     WDC WD20EFRX-68EUZN0
Serial Number:    WD-WCC4MHELCUK3
LU WWN Device Id: 5 0014ee 2b5874ab6
Firmware Version: 82.00A82
User Capacity:    2,000,398,934,016 bytes [2.00 TB]
Sector Sizes:     512 bytes logical, 4096 bytes physical
Rotation Rate:    5400 rpm
Device is:        In smartctl database [for details use: -P show]
ATA Version is:   ACS-2 (minor revision not indicated)
SATA Version is:  SATA 3.0, 6.0 Gb/s (current: 3.0 Gb/s)
Local Time is:    Mon Oct  7 22:33:31 2024 CEST
SMART support is: Available - device has SMART capability.
SMART support is: Enabled

=== START OF READ SMART DATA SECTION ===
SMART overall-health self-assessment test result: PASSED

General SMART Values:
Offline data collection status:  (0x00) Offline data collection activity
                                        was never started.
                                        Auto Offline Data Collection: Disabled.
Self-test execution status:      (   0) The previous self-test routine completed
                                        without error or no self-test has ever 
                                        been run.
Total time to complete Offline 
data collection:                (27060) seconds.
Offline data collection
capabilities:                    (0x7b) SMART execute Offline immediate.
                                        Auto Offline data collection on/off support.
                                        Suspend Offline collection upon new
                                        command.
                                        Offline surface scan supported.
                                        Self-test supported.
                                        Conveyance Self-test supported.
                                        Selective Self-test supported.
SMART capabilities:            (0x0003) Saves SMART data before entering
                                        power-saving mode.
                                        Supports SMART auto save timer.
Error logging capability:        (0x01) Error logging supported.
                                        General Purpose Logging supported.
Short self-test routine 
recommended polling time:        (   2) minutes.
Extended self-test routine
recommended polling time:        ( 273) minutes.
Conveyance self-test routine
recommended polling time:        (   5) minutes.
SCT capabilities:              (0x703d) SCT Status supported.
                                        SCT Error Recovery Control supported.
                                        SCT Feature Control supported.
                                        SCT Data Table supported.

SMART Attributes Data Structure revision number: 16
Vendor Specific SMART Attributes with Thresholds:
ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE      UPDATED  WHEN_FAILED RAW_VALUE
  1 Raw_Read_Error_Rate     0x002f   200   200   051    Pre-fail  Always       -       6
  3 Spin_Up_Time            0x0027   174   167   021    Pre-fail  Always       -       4291
  4 Start_Stop_Count        0x0032   100   100   000    Old_age   Always       -       315
  5 Reallocated_Sector_Ct   0x0033   200   200   140    Pre-fail  Always       -       0
  7 Seek_Error_Rate         0x002e   200   200   000    Old_age   Always       -       0
  9 Power_On_Hours          0x0032   089   089   000    Old_age   Always       -       8512
 10 Spin_Retry_Count        0x0032   100   100   000    Old_age   Always       -       0
 11 Calibration_Retry_Count 0x0032   100   100   000    Old_age   Always       -       0
 12 Power_Cycle_Count       0x0032   100   100   000    Old_age   Always       -       210
192 Power-Off_Retract_Count 0x0032   200   200   000    Old_age   Always       -       138
193 Load_Cycle_Count        0x0032   200   200   000    Old_age   Always       -       1731
194 Temperature_Celsius     0x0022   119   101   000    Old_age   Always       -       28
196 Reallocated_Event_Count 0x0032   200   200   000    Old_age   Always       -       0
197 Current_Pending_Sector  0x0032   200   200   000    Old_age   Always       -       0
198 Offline_Uncorrectable   0x0030   100   253   000    Old_age   Offline      -       0
199 UDMA_CRC_Error_Count    0x0032   200   200   000    Old_age   Always       -       0
200 Multi_Zone_Error_Rate   0x0008   200   200   000    Old_age   Offline      -       0

SMART Error Log Version: 1
No Errors Logged

SMART Self-test log structure revision number 1
Num  Test_Description    Status                  Remaining  LifeTime(hours)  LBA_of_first_error
# 1  Extended offline    Completed without error       00%      8511         -
# 2  Short offline       Completed without error       00%      8478         -
# 3  Conveyance offline  Completed without error       00%      8129         -

SMART Selective self-test log data structure revision number 1
 SPAN  MIN_LBA  MAX_LBA  CURRENT_TEST_STATUS
    1        0        0  Not_testing
    2        0        0  Not_testing
    3        0        0  Not_testing
    4        0        0  Not_testing
    5        0        0  Not_testing
Selective self-test flags (0x0):
  After scanning selected spans, do NOT read-scan remainder of disk.
If Selective self-test is pending on power-up, resume after 0 minute delay.

root@NAS3[~]#

1 Like
43

…at times they do in the title, but you can search in the page or google the model with “CMR”. Is not that hard :slight_smile:

…also, if you can enclose that data you shared with the </> button, it’ll look better :wink:

44

It should be listed on store’s page together with other characteristics. If not, just go to the manufacturer site to check.

For NAS uses, always choose CMR and avoid SMR. SMR are weak against heavy operations such as scrubbing and resilvering, and ZFS did just that.

Here is an interesting article about this topic, so you can take a look:
SMR? CMR? Which Hard Drive is best for which purpose?

1 Like
45

Seagate has a pretty good overview of which drive is smr and cmr on their website: CMR and SMR Hard Drives | Seagate US

46

Sorry… just a question… Are SSD good for this job? or not?

47

Their advantage comparing to standard HDDs is speed. The disadvantage is the price - SSDs are more expensive than HDDs of the same size.

Therefore, you should use SSD for boot pool and HDDs for storage. After that, you can add SSDs for performance improvements / caching, but this is the next level. For the beginning, it is enough to build basic NAS just with boot SSD and data HDDs.

48

Ok thank you for explaination.
I was thinking that maybe an SSD would wear out much faster than an HDD.

49

It will. And just for this reason, it is used for improving performance (system, L2ARC, ZLOG). But for storage, it is too expensive to get several large drives.

Going back to your first post …

… I concluded that this is not a situation where you have hundreds of simultaneous users, so you do not need such a high-end solution. If this is just a home NAS, and there are 1-2 users, there is absolutely no need to spend money on large SSDs. Instead, buy as much as possible HDDs to improve capacity and redundancy.

50

You right, we are in two and use NAS only at certain momento of the months to transfer file from our PC to it.
I would just like to be sure that at this point, TrueNas can be the right solution for me who turns the Nas on and off during the day, and I don’t keep it on for days or weeks.
the computers are in two different rooms, and we use it froma an Nvidia Shield too, so the network starge is the ideal thing for us and having different motherboards/cpu/ram and disks available I would like to use them to not spend more money and buy a Qnap for example, I really wouldn’t want to.

51

no mention about cmr or smr…

52

you can check on List of WD CMR and SMR hard drives (HDD) – NAS Compares

2x WD20EFRX CMR
1x ST2000DM001 SMR
2x ST2000DM008 SMR

1 Like
53

Super question:
I currently have 5 2TB disks for a total of 5x2=10TB (I know, approximate, with the raid it is less, but to give you a rough idea.)
I have to replace the “removed” disk and resilver all… so I have to do it.
BUT. If I replace the 2TB disk with a 4TB disk tomorrow… and then in the future I replace another 3 disks always with 4TB instead of 2TB and I leave 4 in total instead of 5 disks? I would have a system with 4x4=16TB (I know, approximate) but will it work?

  • will the NAS reconfigure itself on a 16TB pool instead of 10TB
  • will the NAS close the pool with 4 disks even if they were originally 5?
54

No, you cannot shrink a raidz vdev. If it was created with 5 drives, it will be “degraded” with 4 or less.
You have to create a new pool to use less drives.

1 Like
55

The exact part number must be listed in the Amazon page.
Go to WD or Seagate homepage and look up for that part number.
If it is clearly stated, it is CMR, you are OK.
If you cant find out, then assume, it is SMR and stay away from it.

56

And, please, dont forget the necessary extra cost for HBAs and rack space either!
SSDs practically top up at 8TB for consumer grade right now that dont have an insane price.
A HDD is available in the 22TB range.