Symptom
Possible Causes
Solution
The serial port
console has no output
or outputs illegible
characters.
The serial port connected to the switch
does not match that opened by the
configuration software.
The serial port is not configured
correctly.
Change the serial port opened by the configuration
software to be the one connected to the switch.
Check that the parameter configuration of the serial
port matches that specified in the instructions.
The RJ45 port is not in
connectivity or it is
erroneous in
receiving/transmitting
frames.
The connected twisted pair cable is
faulty.
The length of the cable exceeds 100 m.
The port has special configuration that
has no common working mode with the
connected switch.
Replace the twisted pair cable.
Check that the port configuration has the common
working mode with the connected switch.
The fiber port cannot
be connected.
The Rx and Tx ends are connected
reversely.
The interconnected optical module type
does not match.
The fiber type is not correct.
The length of the optical fiber exceeds
that rated of the optical module.
Switch the Rx and Tx ends of the optical fiber.
Replace the optical module with one of the
matched type.
Replace the optical fiber with one of the
appropriate type.
Replace the optical fiber with one of the
appropriate length.
The PoE port cannot
be powered.
The PoE function is not enabled.
The connected twisted pair is faulty.
The PD (that is, the powered device,
for example, AP) connected to the port
does not comply with the 802.3af or
802.3at standard.
The serial port control terminal
connected to the PD is not properly
grounded.
The switch is not properly grounded.
Enter interface configuration mode and enable the
PoE function.
Replace the twisted pair.
Replace the current PD with a PD that complies
with the 802.3af or 802.3at standard. For the
RG-S2928G-12P/24P switch, you can enable the
PoE non-standard compatible function to power
the PD.
Ground the serial port control terminal properly and
ensure that the switch is properly grounded. For
the RG-S2928G-12P/24P switch, you can enable
the PoE non-standard compatible function to
power the PD.
Ground the switch properly.
The PoE port indicator
is yellow.
The PD is short-circuited or overloaded
and its power exceeds the power value
distributed to this port by the PoE
switch.
The total power of the PDs connected
to the switch exceeds the rated power
range provided by the PoE switch.
Check whether the rated power of the PD is within
the output power range of the switch. If yes, set the
power distributed to the port by the switch to a
larger value. If the problem persists after the
setting, the PD is damaged. In this case, replace
the PD.
Determine the total power of the PDs. To power a
certain port preferentially, set the priority of this
port to a higher value.
