用aix的备份镜像配置nim源出错

Command: running       stdout: yes           stderr: no

Before command completion, additional instructions may appear below.

Preparing to copy install images (this will take several minutes)...

0042-001 nim: processing error encountered on "master":

   0042-001 m_mk_lpp_source: processing error encountered on "master":

   0042-175 c_mk_lpp_source: An unexpected result was returned by the "/usr/sbin/installp" command:

0503-003 geninstall:  The specified device /nim/sys.img

        is not a valid device or file.

如上，aix使用mksysb制作的备份文件：sys.img，使用sys.img用来配置nim的源，报错为：not a valid device or file.

求大神指点迷津，为什么出现这种情况。