Symptoms

PowerPath paths go to asb:iopf state. The below messages are reported in the /var/adm/messages file: Feb 18 07:59:13 hostname emcp: [ID 801593 kern.notice] Info: Path Bus 3110 Tgt XXXXXXXXXXXXX Lun 53 to CLARiiON ID CKM00000000000 is set to asb:iopf. Feb 18 07:59:13 hostname emcp: [ID 801593 kern.notice] Info: Path Bus 3110 Tgt XXXXXXXXXXXXX Lun 53 moved to iopf with following error sequence Feb 18 07:59:13 hostname emcp: [ID 801593 kern.notice] Info: Path Bus 3110 Tgt XXXXXXXXXXXXX Lun 53, ErrInst 2061db7, TimeStamp 2018 Feb 18 03:00:30 GMT, ErrCode SCSI IO Error Feb 18 07:59:13 hostname emcp: [ID 801593 kern.notice] Info: Path Bus 3110 Tgt XXXXXXXXXXXXX Lun 53, ErrInst 2061db8, TimeStamp 2018 Feb 18 03:00:30 GMT, ErrCode SCSI IO Error Feb 18 07:59:13 hostname emcp: [ID 801593 kern.notice] Info: Path Bus 3110 Tgt XXXXXXXXXXXXX Lun 53, ErrInst 2061db9, TimeStamp 2018 Feb 18 03:00:30 GMT, ErrCode SCSI IO Error Feb 18 07:59:13 hostname emcp: [ID 801593 kern.notice] Info: Path Bus 3110 Tgt XXXXXXXXXXXXX Lun 53, ErrInst 20656e8, TimeStamp 2018 Feb 18 03:58:40 GMT, ErrCode SCSI IO Error

Cause

CRC errors are logged on the switch side due to bad cables.

Resolution

PowerPath is working as designed. When these paths report SCSI IO errors, PowerPath marks them as "asb:iopf," to avoid unstable paths, and to let drive I/O through paths that are active. To understand why these paths are reporting I/O errors, check the changes in the (Fabric, SAN, or Array). This is not a PowerPath issue. In this instance, replacing the cables cleared these errors.

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