Chapter 9. Configuring maximum time for storage error recovery with eh_deadline

• to shut off a failed path,
• to switch a path, or
• to disable a RAID slice.

• If RSCNs are enabled
• If the HBA does not register the link becoming unavailable

Procedure

• You can configure eh_deadline using either of the following methods:

  • defaults section of the multpath.conf file

    From the defaults section of the multpath.conf file, set the eh_deadline parameter to the required number of seconds:

    # eh_deadline 300

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    Note

    From RHEL 8.4, setting the eh_deadline parameter using the defaults section of the multpath.conf file is the preferred method.

    To turn off the eh_deadline parameter with this method, set eh_deadline to off.

  • sysfs

    Write the number of seconds into the /sys/class/scsi_host/host<host-number>/eh_deadline files. For example, to set the eh_deadline parameter through sysfs on SCSI host 6:

    # echo 300 > /sys/class/scsi_host/host6/eh_deadline

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    To turn off the eh_deadline parameter with this method, use echo off.

  • Kernel parameter

    Set a default value for all SCSI HBAs using the scsi_mod.eh_deadline kernel parameter.

    # echo 300 > /sys/module/scsi_mod/parameters/eh_deadline

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    To turn off the eh_deadline parameter with this method, use echo -1.