The GET_HOST_POWER_STATUS command requests the power state of the server. For this command to parse correctly, the GET_HOST_POWER_STATUS command must appear within a SERVER_INFO command block. You can set SERVER_INFO MODE to read.
Example:
<RIBCL VERSION="2.0">
<LOGIN USER_LOGIN="adminname" PASSWORD="password">
<SERVER_INFO MODE="read">
<GET_HOST_POWER_STATUS/>
</SERVER_INFO>
</LOGIN>
</RIBCL>