HP Jetdirect 250M User Manual page 210

10/100 link OK? (10 light or 100 light ON
solid green?)
The link lights -- the 10 light and the 100 light -- indicate whether the
print server can establish a network link at the right speed with your hub,
switch, or router. One of the link lights -- either the 10 light or the 100
light -- should be ON solid green (bright green in color and glowing
continuously, not blinking) to indicate a valid link with the
hub/switch/router. If there is not a valid link, then both the 10 and 100
lights will be off.
If one of the print server's link lights is ON solid green, click on
the Yes button below to return to the Troubleshooting Overview page and
continue with the next step in the troubleshooting procedure.
If neither of the print server's link lights is ON solid green, or if
you are not sure what to look for, click on the No button below to
start evaluating the link status of the print server. Clicking the No button
will also give you information on where to find the link lights, what they
look like, and what the correct network connection looks like.