x2250上装xVM Server的报错

用Ops Center 2.1在x2250上安装xVM Server，Console上如下报错，在另一台相同配置的x2250上却能正常安装。以后有机会再查查原因。

kernel 5/platform/i86pc/kernel/unix -v install -B install_config=129.200.9.201:
/var/js,sysid_config=129.200.9.201:/var/js/Profiles/sysid/1,install_media=129.2
00.9.201:/var/js/5,console=ttya
module 5/x86.miniroot

Error 20: Multiboot kernel must be loaded before modules
  Booting 'xVM Server Install'

kernel 5/platform/i86pc/kernel/unix -v install -B install_config=129.200.9.201:
/var/js,sysid_config=129.200.9.201:/var/js/Profiles/sysid/1,install_media=129.2
00.9.201:/var/js/5,console=ttya
module 5/x86.miniroot

Error 20: Multiboot kernel must be loaded before modules
  Booting 'xVM Server Install'

kernel 5/platform/i86pc/kernel/unix -v install -B install_config=129.200.9.201:
/var/js,sysid_config=129.200.9.201:/var/js/Profiles/sysid/1,install_media=129.2
00.9.201:/var/js/5,console=ttya
module 5/x86.miniroot

Error 20: Multiboot kernel must be loaded before modules

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