Changes between Version 57 and Version 58 of FAQ


Ignore:
Timestamp:
Feb 26, 2016, 4:54:39 PM (4 years ago)
Author:
Alex Samorukov
Comment:

Reference ticket #658 in the ERC FAQ item

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  • FAQ

    v57 v58  
    202202In computing, error recovery control (ERC) is a feature of hard disks which allow a system administrator to configure the amount of time a drive's firmware is allowed to spend recovering from a read or write error. Limiting the recovery time allows for improved error handling in hardware or software RAID environments. In some cases, there is a conflict as to whether error handling should be undertaken by the hard drive or by the RAID implementation, which leads to drives being marked as unusable and significant performance degradation, when this could otherwise have been avoided.
    203203
    204 It is best for ERC to be "enabled" when in a RAID array to prevent the recovery time from a disk read or write error from exceeding the RAID implementation's timeout threshold. If a drive times out, the hard disk will need to be manually re-added to the array, requiring a re-build and re-synchronization of the hard disk.
     204It is best for ERC to be "enabled" when in a RAID array to prevent the recovery time from a disk read or write error from exceeding the RAID implementation's timeout threshold. If a drive times out, the hard disk will need to be manually re-added to the array, requiring a re-build and re-synchronization of the hard disk. Limiting the drives recovery timeout helps for improved error handling in the hardware or software RAID environments.
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    206206On disks that fully implement the ATA-8 standard, the smartctl utility  can be used to control the ERC behavior of many drives by setting the SCT Error Recovery Control (scterc) parameter:
     
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    224 ERC control needs to be set on the boot time and if hot-replacement been made. 
     224ERC control needs to be set on the boot time and if hot-replacement been made.  You may find sample Linux scripts and related discussion in the ticket #658.
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