meaning of if_snd full

[Mike Pearlman]

Recently, a diskless 3/60 has been hanging. Upon inspection, /usr/adm/messages
contains a stream of

	nd: output error 55
	le0: WARNING: if_snd full

Can someone explain what these messages mean. The server is showing no
problems. These messages have just started appearing and there have been
no major changes to the network in the recent past. Please, reply directly
to me so that I can take care of the problem. I will summarize to
sun-spots.

thanks

michael pearlman <canuck at rice.edu>