Yes, RS232 9600/8/N/1 into a RS232 TTL to USB converters from ebay. Wire is 2 pair 28 gauge, longest run is about 150 feet. The RS232 TTL to USB converters all plug into a 7 port USB hub.
I like to have my ports show up in the same order and with unique names so I have the following /etc/udev/rules.d/99-usb-serial.rules file:
SUBSYSTEM=="tty", KERNELS=="2-1.3.1.1", SYMLINK+="ttyPort0", GROUP="dialout", MODE="0666"
SUBSYSTEM=="tty", KERNELS=="2-1.3.1.2", SYMLINK+="ttyPort1", GROUP="dialout", MODE="0666"
SUBSYSTEM=="tty", KERNELS=="2-1.3.1.3", SYMLINK+="ttyPort2", GROUP="dialout", MODE="0666"
SUBSYSTEM=="tty", KERNELS=="2-1.3.1.4", SYMLINK+="ttyPort3", GROUP="dialout", MODE="0666"
SUBSYSTEM=="tty", KERNELS=="2-1.3.2", SYMLINK+="ttyPort4", GROUP="dialout", MODE="0666"
SUBSYSTEM=="tty", KERNELS=="2-1.3.3", SYMLINK+="ttyPort5", GROUP="dialout", MODE="0666"
SUBSYSTEM=="tty", KERNELS=="2-1.3.4", SYMLINK+="ttyPort6", GROUP="dialout", MODE="0666"
SUBSYSTEM=="tty", KERNELS=="2-1.4.4", SYMLINK+="zwave", GROUP="dialout", MODE:="0666"
If you use custom names you need /etc/default/openhab2 file:
EXTRA_JAVA_OPTS="-Dgnu.io.rxtx.SerialPorts=/dev/zwave:\
/dev/ttyPort0:/dev/ttyPort1:/dev/ttyPort2:/dev/ttyPort3:/dev/ttyPort4:/dev/ttyPort5:/dev/ttyPort6 \
-Dfile.encoding=ISO-8859-1 -Duser.timezone=America/New_York"