# Cable connection guidelines for Engines

The cabling of Engines depends on the engine type and the installation.

Make sure that all Ethernet cables are correctly rated (CAT 5e or CAT 6 in gigabit networks).

If you have a two-node Engine Cluster, it is recommended to use a crossover cable without any intermediary devices between the nodes. If you use an external switch between the nodes, follow these guidelines:

- Make sure that portfast is enabled on the external switches.
- Make sure that the speed/duplex settings of the external switches and the Engine devices are set to Auto.
- Configure the external switches to forward multicast traffic.

For layer 2 physical interfaces on Engines, follow these cable connection guidelines:

- Capture interfaces — Follow the cable connection guidelines for IPS and Layer 2 Engines.
- Inline IPS interfaces — Follow the cable connection guidelines for IPS.
- Inline Layer 2 Engine interfaces — Follow the cable connection guidelines for Layer 2 Engines.