PSOD on ESXi 6.x host after OS upgrade


   Article Number:     499644                                   Article Version: 3     Article Type:    Break Fix 










      When the host is coming up after ESXi OS upgrade or any further reboot with SDC installed to ESXi 6.0 or 6.5 it can panic and throw following PSOD:   


        User-added image   


      kernel BUG at /home/sharon/projects/src/ini/vmware/blk/blk_dev.c:249!   

      PanicvPanicInt@vmkernel#nover+0x37e stack: 0x4390e9e1ab58         
          Panic_vPanic@vmkernel#nover+0x23 stack: 0x4390e9e1abc0         
          vmk_PanicWithModuleID@vmkernel#nover+0x41 stack: 0x4390e9e1abb0
      With ESXi panicking after every reboot, the whole operating system is unusable.   







      This problem appears after upgrading ESXi with SDC installed from ESXi 5.x to 6.x without removing SDC 5.5 before the upgrade.   








      Root cause   


      The SDC installed with ESXi 5.5 does not support ESXi 6.0 & 6.5. When upgrading ESXi 5.5 to 6.0 or 6.5, the ESXi 5.5 SDC should be uninstalled, prior to starting the upgrade.   




      If the OS is already upgraded, revert back to ESXi 5.5, manually uninstall SDC 5.5, then proceed with the OS upgrade and SDC 6.x installation. If the upgrade process haven't started, remove SDC 5.5 before upgrading the OS.   


      ESXi can be downgraded using following VMware procedure:     


      Permanent Fix   


      ScaleIO will have some improvement for VUM and won't allow SDC 5.x to be installed on ESXi 6.x machine. ScaleIO documentation (Release Notes) will be also updated to ensure this problem is clearly documented.