By default, the routing platform’s management Ethernet interface, fxp0, autonegotiates whether to operate in full-duplex or half-duplex mode. Fast Ethernet and J-series Services Router Gigabit Ethernet interfaces can operate in either full-duplex or half-duplex mode, and all other interfaces can operate only in full-duplex mode. For Gigabit Ethernet, the link partner must also be set to full duplex.
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Note: When you configure the Tri-Rate Ethernet copper interface to operate at 1 Gbps, autonegotiation must be enabled. |
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Note: When you manually configure Fast Ethernet interfaces on the M-series and T-series routers, link mode and speed must both be configured. If both these values are not configured, the router uses autonegotiation for the link and ignores the user-configured settings. |
To explicitly configure an Ethernet interface to operate in either full-duplex or half-duplex mode, include the link-mode statement at the [edit interfaces interface-name] hierarchy level:
- [edit interfaces interface-name]
-
link-mode (full-duplex
| half-duplex);