Locating issues:  Although IBM Spectrum Virtualize raises error messages, most events  are not caused by IBM Spectrum Virtualize. Most issues are introduced by the storage  subsystems or the SAN. If the problem is caused by IBM Spectrum Virtualize and you are unable to fix it by using the  Recommended Action feature or the event log, collect the IBM Spectrum Virtualize support  package as described in 10.4.1, “Collecting data from IBM Spectrum Virtualize” on page 444.  To identify and fix other issues outside of IBM Spectrum Virtualize, consider the guidance in  the other sections in this chapter that are not related to IBM Spectrum Virtualize. When IBM Spectrum Virtualize detects a failed NVMe (Storwize V7000 Gen3 only), Flash or  HDD disk drive, it automatically generates an error in the  Events  panel. To replace the failed  disk drive, always run  Fix Procedure  for this event in the  Monitoring  Events  panel. The  Fix Procedure  will help you to identify the enclosure and slot where the bad drive is  located, and will guide you to the correct steps to follow in order to replace it. When a drive  fails, it is removed from the array. If a suitable spare drive is available, it is taken into the array  and the rebuild process starts on this drive. After the failed drive is replaced and the system detects the replacement, it reconfigures the  new drive as spare. So, the failed drive is removed from the configuration, and the new drive  is then used to fulfill the array membership goals of the system. Apart from hardware-related situations, problems can exist in such areas as the operating  system or the software that is used on the host. These problems normally are handled by the  host administrator or the service provider of the host system. However, the multipathing driver  that is installed on the host and its features can help to determine possible issues.  Example 10-8 shows a volume path issue reported by SDD output on the host by using the  datapath query adapter  and  datapath query device  commands. The adapter in degraded  state means that specific HBA on the server side can’t reach all the nodes in the I/O group  which the volumes are associated. Also we can notice in the  datapath query device command output that each device (or volume) has only three paths, when it is expected to  have four paths. Replacing a failed NVMe, flash or disk drive 10.5.2 Solving host problems Chapter 10. Troubleshooting and diagnostics  451 Example 10-8 SDD output on a host with faulty paths  C:\Program Files\IBM\SDDDSM> datapath query adapter Active Adapters :2 Adpt# Name Interface State Mode Select Errors Paths Active 0 Scsi Port2 Bus0 FC DEGRAD ACTIVE 1860589 293 4 4 1 Scsi Port3 Bus0 FC NORMAL ACTIVE 1979793 259 8 8 C:\Program Files\IBM\SDDDSM> datapath query device Total Devices : 8 DEV#: 0 DEVICE NAME: Disk2 Part0 TYPE: 2145 POLICY: LEAST I/O AND WEIGHT SERIAL: 600507680C838020E80000000000001B Reserved: No LUN SIZE: 5.0GB