Enterasys Matrix 7G4280-19, Hardware Installation Manual, Page: 48 / 92

Connecting to the Network
3-18 Installation
4. Verify that a link exists by checking that the port RX (Receive) LED is ON (flashing
amber, blinking green, or solid green).
5. If the RX LED is OFF and the TX (Transmit) LED is not blinking amber, perform the
following steps until it is on:
a. Verify that the cabling being used is Category 5 UTP with an impedance between
85 and 111 ohms. Category 5 cabling must be used for 1000 Mbps operation.
b. Verify that the device at the other end of the twisted pair segment is on, and
properly connected to the segment.
c. Verify that the RJ45 connectors on the twisted pair segment have the proper
pinouts and check the cable for continuity. Typically, a crossover cable is used
between hub devices. A straight ‐ through cable is used to connect between
switches or hub devices and an end user (computer). Refer to Figure 3 ‐ 9 and
Figure 3 ‐ 10 for four ‐ wire RJ45 connections. Refer to Figure 3 ‐ 11 and Figure 3 ‐ 12
for eight ‐ wire RJ45 connections.
Figure 3-9 Four-Wire Crossover Cable RJ45 Pinouts, Connections Between Hub
Devices
Note: When installing Mini-GBICs in the front-panel ports 1 through 18, you may need
to select a group of ports to verify the port operation. Initially GROUP 1 LED is green,
indicating that the status RX/TX LEDs are showing the activity on Group 1 ports
(1 through 6). To view the receive and transmit activity on another group, press the
GROUP SELECT button for less than one second (refer back to
Figure 3-7 ) to step to
the next GROUP (1, 2, or 3) of 6 ports. The receive and transmit activity for that group
of segments is then indicated by the RX and TX LEDs for each segment.
1 RJ45 device port 3 RJ45-to-RJ45 crossover cable
2 Other device port 4 RX+/RX- and TX+/TX- connections.
These connections must share a common color pair.
TX+
TX–
RX+
RX– 2
1
3
6
TX+
TX–
2
1
3
6
RX+
RX–
À Á
Â
Ã