我应该是在清理服务器磁盘的时候误删了该磁盘的快照文件，强制删除了，命令如下：
lvremove /dev/VG_XenStorage-a63bd904-e742-20e3-359e-ad2d1f9a5f45/VHD-7b566a5c-a013-4285-9491-341238a8de32 --config global{metadata_read_only=0}

lvdisplay /dev/VG_XenStorage-a63bd904-e742-20e3-359e-ad2d1f9a5f45/VHD-7b566a5c-a013-4285-9491-341238a8de32

fuser -kuc /dev/VG_XenStorage-a63bd904-e742-20e3-359e-ad2d1f9a5f45/VHD-18637599-cdf7-4193-8115-9d63e0c3c05f

然后这个数据盘也不能用了，报错。

Jan 25 19:35:19 xenserver-192 xapi: [error|xenserver-192|7457 ||backtrace] Async.VBD.plug R:3f166e98f9da failed with exception Server_error(SR_BACKEND_FAILURE_453, [ ; tapdisk experienced an error [opterr=No such file or directory]; ])
Jan 25 19:35:19 xenserver-192 xapi: [error|xenserver-192|7457 ||backtrace] Raised Server_error(SR_BACKEND_FAILURE_453, [ ; tapdisk experienced an error [opterr=No such file or directory]; ])
Jan 25 19:35:19 xenserver-192 xapi: [error|xenserver-192|7457 ||backtrace] 1/1 xapi @ xenserver-192 Raised at file (Thread 7457 has no backtrace table. Was with_backtraces called?, line 0
Jan 25 19:35:19 xenserver-192 xapi: [error|xenserver-192|7457 ||backtrace]