Trying to install the collector the installer fails at this point:
Middle-tier Host (DEFAULT: myserver):
Middle-tier Communication Port (DEFAULT: 3566):
-Checking for an existing installation
-Detecting installation directory
-Detecting delivered agent version
-Checking for sufficient disk space
internal issue has occurred. Please retry the last operation to continue the installation
Disk space issue on middleware host. The install log contains the following...
Message(SCException): "API function: "Checking for sufficient disk space" ("getFreeSpaceInKBInternal") Failed. Return Code: "-85004", Return Message: "Failed to get_disk_free_space" "
Add disk space to the middleware server or free up some disk space by removing unnecessary files from the middleware server on the filesystem where the middleware is installed. The middleware for the PAO v7.0 and above requires minimum 4GB per collector instance sharing the middleware. Once there is enough disk space, try the installation again.