The link checker is flagging all internal links as having connection issues, 'Connection Failed'.
The logs show:
1. Log : couldn't connect to host [Error #7]
=== (No response) ===
Link is broken.
...with the same response time for EVERY link: # Response time : 3.003 seconds
This seems to be happening with every internal link on the site, but external links are checked fine.
We increased max. execution time and timeout. Server load sits at .34, max set at 4.