Description
This article provides some technical specs on the 'Self-Loopback' cable mentioned in HQIP hardware tests.
The details below should help to use the proper cable.
Scope
FortiGate.
Solution
The Self-loopback cable is a special wired cable where the TX lane and RX lanes are 'looped' as illustrated below:
For the regular cabling (Cat5, 100Mbps).
- Orange and Orange/White are often used to transmit data and may be referred to as transmit pairs.
- Green and Green/White are often used to transmit data and may be called receive pairs.
- Brown and Blue ones are used for other purposes (signal mirroring/noise correction).
For the Gigabit standard over regular cabling (Cat5, 1000Mbps).
- All 4 of the wire pairs are used for data transmission.
- The difference is in signal level (4 levels: 00/01/10/11, instead of the regular 2: 0/1) and clock rate.
During HQIP Tests, it may be required to plug a 'SELF-LOOPBACK' into interfaces so they can be tested, and in the example below, the HA port should receive a self-loopback cable while the other ports should be plugged into each other as described.
dia hardware test network
Network Interface Loopback Test - Please connect ethernet cables:
[HA - SELF-LOOPBACK] [MGMT - Any of PORT1...PORT16] [PORT17 - PORT18] ... [PORT23 - PORT24] [X1 - X2] [x3 - x4]
Do you want to continue this test? (y/n) (default is n) y
If it is necessary to plug a self-loopback cable during the HQIP test, use a cable with the technical specifications above.
The HQIP test checks the ports at 1000Mbps speed. If this speed is not achieved, ensure the loopback connection has all 4 wire pairs connected.
The LED will only start to blink during the 'Network Interface Detection' test. This phenomenon is normal.
... ==> Network Interface Detection
Interface MAC Linkage CurrentSpeed CurrentDuplex SettingSpeed Default(Supported)
--------------------------------------------------------------------------------------
dmz 90:6C:AC:00:00:01 Linked 1000 FULL auto (1000baseT_Full)
ha1 90:6C:AC:00:00:02 Linked 1000 FULL auto (1000baseT_Full)
ha2 90:6C:AC:00:00:03 Linked 1000 FULL auto (1000baseT_Full)
lan1 90:6C:AC:00:00:04 Not linked HALF auto (1000baseT_Full)
Fortinet does not include a self-loopback cable in the product box.
Usually, only one such cable is needed for the models with the odd number of ports.
Include the output of 'get system status' with the HQIP results.
Related article:
Hardware troubleshooting with built-in FortiOS hardware diagnostic commands
