TITLE: Drive Deactivation Troubleshooting Tips DOCUMENT ID#: FYI.P.11081 DATE: 12JAN93 PRODUCT: NetWare PRODUCT VERSION: v3.11 SUPERSEDES: NA SYMPTOM NA ISSUE/PROBLEM Drive Deactivation Tips and Techniques for NetWare v3.11. The purpose of this document is to establish what drive deactivation is and why it occurs. Drive deactivation is when one or more devices (drives) in the server become unable to communicate with the operating system (OS). Drive deactivation is caused by an inability of NetWare and the disk driver to communicate with the device. When the driver cannot communicate with the drive, it will normally retry several times. If, after a predetermined number of retries, the driver still cannot establish a communication link with the drive, the driver tells the OS that the drive is not responding and the OS then deactivates the device. Drive deactivation can occur across any of the disk interfaces, such as IDE, ESDI, or SCSI. Drive deactivation is also not confined to just one manufacturer. The following list is a "checklist" that Novell suggests you go through in troubleshooting a drive deactivation problem. In many cases, you must be very specific with hardware, firmware, and software revision levels as you work with your third-party Host Bus Adapters (HBAs) and drive manufacturers in solving your problems. The priority of the checklist is based on solutions that will cost the least and still receive the highest priority. For checklist purposes, this discussion will be restricted to the SCSI interface. All suggestions should be easily translated for any interface. CHECKLIST 1. Verify that termination along the SCSI bus is correct. The first basic rule to remember is that both ends of the bus must be terminated. You must be careful that if you have drives in an internal or external cabinet that you remove the termination from the individual drives and then just terminate the cabinet externally. This avoids future headaches; because, as you add more drives, you do not have to worry about which drive was terminated in which cabinet. Another problem arises when you use both the internal and external ports on an HBA. When you do this, you must remove the termination from the HBA and terminate both ends of the SCSI bus, which will usually be at the drives themselves unless an external cabinet is used. 2. Verify that the SCSI IDs are set properly. In all situations, the HBA will have a SCSI ID of 7. This may be set either through a hardware setting (jumpers) or through software utilities (such as EISA CONFIGURATION or REFERENCE). In PS/2 situations and possibly with HPs, the HBA takes a SCSI ID of 7 and the attached devices start at 6 and work down to 0. In all other situations, the HBA takes an ID of 7, and the attached devices start at 0 and work up to 6. In the PS/2 environment, there are specific things that need to be addressed. þ Under reference, the "fairness" needs to be turned ON for the HBA. þ Using the OPTION diskette v1.0 from IBM, the settings for Fairness are reversed. Normally, fairness is turned ON. However, if you are using the OPTIONS diskette v1.0, you must set "Fairness" to OFF. On all other versions of the OPTIONS diskette, simply set fairness to the normal setting of ON. 3. Verify the disk driver. Verify with your third-party HBA manufacturer that you are running the latest Novell certified driver and that it is compatible with the firmware revision level on your HBA. 4. Verify the HBA firmware. Verify with your third-party HBA manufacturer that the version of firmware on your HBA is the correct version applicable to the version of the disk driver that you are using. 5. Verify the firmware revision level on the drive. Verify with the third-party drive manufacturer that you have the proper or latest version of firmware on your drive. 6. Check and if necessary replace the cabling on the SCSI bus. Reseat all connectors, then reseat the HBA into the bus. Look for pinched or broken leads on all connectors and cables. 7. Verify proper wattage of the power supply. Novell had seen many drive deactivation problems solved by upgrading or replacing a weak or flaky power supply. Drive deactivation problems seem to be an ever increasing problem as drives grow larger in capacity yet shrink in physical size. This smaller size allows more drives to be placed into the server box itself thus placing a larger demand on the server's power supply. 8. Examine other devices attached to the SCSI bus. If you have a tape unit, CD-ROM, or other devices attached to the SCSI bus, ensure you enable the "disconnect" feature on those devices. This allows the HBA to issue a command or series of commands to that device and then disconnect and return to servicing disk requests. If the "disconnect" feature is not enabled, the SCSI bus must wait for the device to return with a completion code and by so doing may not be able to service the drivers requests to "talk" to the drive. 9. Examine other bus mastering boards. If your server has bus mastering boards, you may need to examine these closely. If a bus mastering board holds the bus too long, this may prevent the disk driver from establishing a communication link with the drive. Sometimes it may be an issue of getting a newer driver for the bus mastering device or taking drastic steps of replacing or upgrading the suspected bus mastering device. Experience has shown that this can happen, but it is rare. 10. Replace the HBA. If the above steps have failed to solve the drive deactivation problem, then it is time to take drastic action. Replace the HBA with preferably the same make and model number. If a different brand or model number is chosen, a reformatting and repartitioning of the drive may be necessary. 11. If you are still unsuccessful in solving the drive deactivation, it is time to seriously look at replacing the drive. Experience has shown that replacing the drive with the same make and model number may solve the problem; however, in some situations a switch to a different manufacturer may be necessary. Drive deactivation can sometimes be very finicky and may require drastic steps to stabilize the server and eliminate the drive deactivations. SOLUTION NA