kdump service fails with message "kexec_file_load failed: Required key not available"

Issue

• kdump service gets failed with the following error messages:

  * kdump.service loaded failed failed Crash recovery kernel arming
  * kdump.service - Crash recovery kernel arming
    Loaded: loaded (/usr/lib/systemd/system/kdump.service; enabled; vendor preset: enabled)
   Process: 25875 ExecStart=/usr/bin/kdumpctl start (code=exited, status=1/FAILURE)
  localhost.localdomain dracut[27907]: *** Creating initramfs image file '/boot/initramfs-3.10.0-957.el7.x86_64kdump.img' done ***
  localhost.localdomain kdumpctl[25875]: Secure Boot is enabled. Using kexec file based syscall.
  localhost.localdomain kdumpctl[25875]: kexec_file_load failed: Required key not available
  localhost.localdomain kdumpctl[25875]: kexec: failed to load kdump kernel
  localhost.localdomain kdumpctl[25875]: Starting kdump: [FAILED]
  localhost.localdomain systemd[1]: kdump.service: main process exited, code=exited, status=1/FAILURE
  localhost.localdomain systemd[1]: Unit kdump.service entered failed state.
  localhost.localdomain systemd[1]: kdump.service failed.