Understanding network problem (syslog)

I am running a lubuntu 14.04 server and its always worked well, except for the last couple of days it keeps dropping off the LAN. I am using a couple of powerlink adapters to connect it up as WiFi was never very solid on it.

Anyway, I plugged a screen and mouse/keyboard into it to try to work out whats up with it, and I tailed the syslog. Here is an excerpt: http://ift.tt/1B2DNFU

Can someone please give me any clues to what might the problem be? Or any tips on how to track down the issue.

I have uplugged the ethernet cable from my router and rebooted it all, to no avail.

Many thanks, Chris