How to perform a NAS memory test with memtester (without HDMI or GPU)

Applicable Products

• All QNAP NAS models running QTS or QuTS hero

Overview

Faulty memory can cause system instability or data corruption. You can check your NAS's memory health in QTS by installing memtester through Entware QPKG. 

Note: Running memory tests can disrupt NAS services. Back up your important data and perform these steps during a maintenance window.
Tip: The OOM (Out Of Memory) Killer is a process in Linux that terminates applications if the system runs out of memory. Test only a portion of total memory to avoid system instability.

Procedure

Step 1: Install memtester utility

Download memtester utility and extract and save it into Public shared folder

Step 2: Stop all NAS services

Warning: Stopping all services will interrupt access to shared folders, applications, and network services. Make sure no users are actively accessing the NAS before proceeding.

sudo /etc/init.d/services.sh stop

Step 3: Check Available Memory

sudo free -g
             total       used       free     shared    buffers     cached
Mem:            62          9         53          0          0          4
-/+ buffers/cache:     4         58
Swap:           22          0         22

The free memory is around 53GB.

Step 4: Run Memtester

Test on free memory (aorund 80–90% of the total memory to avoid triggering the OOM Killer). 

sudo chmod +x  /share/Public/memtester.*
sudo /share/Public/memtester.{x64/armv7/arm64} 53G 1

• memtester.x64 / memtester.armv7 / memtester.arm64: Choose the one which fit in with your NAS platform to run.
• 53G: Free memory size to test (around 80–90% of total RAM, e.g, 64GB).
• 1: Number of test loops to run.

Step 5: Interpret Results

If you see repeated FAILURE messages, your memory module may be defective and should be replaced.

memtester version 4.7.1 (64-bit)
Copyright (C) 2001-2024 Charles Cazabon.
Licensed under the GNU General Public License version 2 (only).

pagesize is 4096
pagesizemask is 0xfffffffffffff000
want 54272MB (56908316672 bytes)
got  54272MB (56908316672 bytes), trying mlock ...locked.
Loop 1/1:
  Stuck Address       : ok
  Random Value        : ok
  Compare XOR         : ok
  Compare SUB         : ok
  Compare MUL         : ok
  Compare DIV         : ok
  Compare OR          : ok
  Compare AND         : ok
  Sequential Increment: ok
  Solid Bits          : testing  43FAILURE: 0xffffffffffffffff != 0xffffdfffffffffff at offset 0x00000000082b72a8.
  Block Sequential    : testing 159FAILURE: 0x9f9f9f9f9f9f9f9f != 0x9f9fbf9f9f9f9f9f at offset 0x00000000082b56e8.
  Checkerboard        : testing   2FAILURE: 0xaaaaaaaaaaaaaaaa != 0xaaaa8aaaaaaaaaaa at offset 0x00000000082b72a8.
  Bit Spread          : testing   0FAILURE: 0xfffffffffffffffa != 0xffffdffffffffffa at offset 0x00000000082b72a8.
  Bit Flip            : testing   2FAILURE: 0x0000000000000001 != 0x0000200000000001 at offset 0x00000000082b56e8.
  Walking Ones        : testing  12FAILURE: 0xffffffffffffefff != 0xffffdfffffffefff at offset 0x00000000082b5608.
FAILURE: 0xffffffffffffefff != 0xffffdfffffffefff at offset 0x00000000082b72a8.
  Walking Zeroes      : testing  16FAILURE: 0x0000000000010000 != 0x0000020000010000 at offset 0x00000000082b5238.
FAILURE: 0x0000000000010000 != 0x0000200000010000 at offset 0x00000000082b56e8.
  8-bit Writes        : ok
  16-bit Writes       : ok

Step 6: Start all NAS services

Once testing is complete, restart all NAS services to restore normal operation:

sudo /etc/init.d/services.sh start

Reminder: After restarting, check that all expected NAS services are running normally.

Step 7: Removing memtester utility

Remove memtester utility if you don't need it anymore.

sudo rm -f /share/Public/memtester.*

Further Reading

How do I perform a Memory test on QNAP NAS ?