Hard Disk errors on QFX3100 switch

Hard Disk errors are incrementing on QFX3100 switch

• We could use the below command to check the Hard Drive errors on switch :

smartctl -a /dev/sg0 -T permissive

• We need to check for Reallocated_Sector errors as shown below :

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ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE

1 Raw_Read_Error_Rate 0x002f 197 192 051 Pre-fail Always - 20

5 Reallocated_Sector_Ct 0x0033 200 200 140 Pre-fail Always - 4

196 Reallocated_Event_Count 0x0032 197 197 000 Old_age Always - 3

197 Current_Pending_Sector 0x0032 200 200 000 Old_age Always - 2

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When the hard drive finds a read/write/verification error, it marks that sector as reallocated and transfers data to a special reserved area (spare area). This process is also known as remapping, and reallocated sectors are called remaps. The raw value normally represents a count of the bad sectors that have been found and remapped. Thus, the higher the attribute value, the more sectors the drive has had to reallocate. This allows a drive with bad sectors to continue operation; however, a drive which has had any reallocations at all is significantly more likely to fail in the near future.

By default value of the concerned attribute is 0. However, if the attribute value keeps incrementing, then the recommendation is to replace the HDD.

2023-12-11 : Article Created

2026-09-30 : Externalized