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Unsure whether a switch port is working: how do you read the LEDs?

Switch LEDs tell you in 5 seconds whether the issue is in the cable or in software.

Try this first

  1. 1Light off with cable plugged in? Then there is no link. Try another cable or another port.
  2. 2Light blinking orange or yellow? Often that is 100 Mbit instead of 1 Gbit. Not broken, but half speed.
  3. 3Steady green or blue? Link is fine; the issue is higher up (DHCP, firewall, software).
  4. 4Lights flashing wildly on all ports at once? Possibly a loop in your network. Pull suspect cables and see if it stops.

When to bring us in

An unknown loop on your network calls for spanning-tree settings or port filters. Do not experiment during office hours. Call us; usually fixed in 30 minutes.

See also

None of the above fits?

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