8 pin RJ45 (8P8C) male connector
8 pin RJ45 (8P8C) male connector
The Cisco rollover cable — also called a console cable — is an RS-232 asynchronous serial cable used to connect a PC or terminal to the console port of Cisco IOS-based routers, switches, and security appliances for initial configuration and management. It uses 8P8C (commonly called RJ-45) plugs at both ends and reverses all eight conductors end-to-end: pin 1 at one end connects to pin 8 at the other, pin 2 to pin 7, and so on. The rollover cable has been standard equipment with Cisco hardware since the early 1990s and is paired with an RJ-45-to-DB-9 or RJ-45-to-DB-25 adapter to reach a PC serial port.
To identify a rollover cable, hold the two plugs side by side with the tabs facing back: the wire on the outside pin of the left plug will be the same colour as the wire on the outside pin of the right plug. On Cisco-supplied cables, pin 1 is white on one connector and pin 8 is white on the other.
| Router Pin name | Router Pin | Direction | Workstation Pin | Workstation Pin name |
|---|---|---|---|---|
| White-Orange | 1 | IN/OUT | 8 | brown |
| orange | 2 | IN/OUT | 7 | White-Brown |
| White-Green | 3 | IN/OUT | 6 | green |
| blue | 4 | IN/OUT | 5 | White-Blue |
| White-Blue | 5 | IN/OUT | 4 | blue |
| green | 6 | IN/OUT | 3 | White-Green |
| White-Brown | 7 | IN/OUT | 2 | orange |
| brown | 8 | IN/OUT | 1 | White-Orange |
Notes
The console port on Cisco devices is DCE (data communications equipment). The RJ-45 connector carries RS-232 asynchronous signals; the cable itself carries no Ethernet traffic. A separate RJ-45-to-DB-9 TERMINAL adapter is required to connect to a PC COM port. Signal assignment at the router end: pin 1 = RTS, pin 2 = DTR, pin 3 = TxD, pin 4 = GND, pin 5 = GND, pin 6 = RxD, pin 7 = DSR, pin 8 = CTS. The rollover cable is not interchangeable with a straight-through or crossover Ethernet patch cable.