The relevant line is:
[25/Apr/2017:04:31:18][2199.7fd523b08700][-driver:nssock_v4:0-] Error: Ns_SockBinderListen: sendmsg() failed: sent 53 bytes, 'Address already in use'^[[0m
to figure out, what's running on that port, use:
You can either stop the service using port 8000 on your machine, or you can alter the port, on which OpenACS is listening by modifying the config file
(look for "httpport"). As long the port is higher than 1024, changing this number is sufficient. For using privileged ports, one has to adjust the service file as well (look into the oacs-5-9.service file).