Allied Telesis AlliedWare Plus GS980MX Series Installation Manual page 241

Problem 5: The SHOW STACK command is not displaying all the
switches in the stack.
Solutions: If you are using 10Gbps ports for the stack trunk, try the
following:
Verify that the stacking ports are properly cabled. Refer to

Chapter 10, "Cabling the Networking Ports" on page 231.
If you are using SFP+ transceivers for the stack trunk, verify that

they are fully inserted into the transceiver ports.
If you are using SPI0TW direct connect twinax cables, verify that

they are from Allied Telesis. The trunk will not work with cables
from other network equipment manufacturers.
Verify that VCStack is activated on the switches. For instructions,

refer to Chapter 7, "Building the Trunk with the Default 10Gbps
Stacking Ports" on page 141.
Problem 6: The GS980MX/10HSm, GS980MX/18HSm, GS980MX/
28PSm or GS980MX/52PSm switch is not providing power to a PoE
device.
Solutions: Try the following:
Check the port's PoE LED. If the LED is flashing amber, the switch

has reached its maximum power budget and cannot support any
additional PoE devices.
Review the powered device's documentation to verify that it is

compatible with the switch. Refer to "Powered Device Classes" on
page 45 and"Wiring Implementation" on page 47.
Use the SHOW SYSTEM ENVIRONMENT command to confirm

that both power supplies are operating normally.
Use the management software to determine whether the switch

has reached its maximum power budget and cannot support any
further powered devices. The maximum power budget is:
– GS980MX/10HSm: 500W with one power supply
– GS980MX/18HSm: 720W with one power supply
– GS980MX/28PSm: 370W with one power supply
– GS980MX/52PSm: 370W with one power supply
Verify that you are using the appropriate category of twisted-pair

cable by referring to "Cable Requirements" on page 34.
Use the management software on the switch to determine whether

PoE is enabled on the port. The default setting for PoE is enabled.
Use the management software on the switch to determine whether

the PoE power setting for the port has been reduced to a value
below the power requirements of the device.
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