apache挂掉的奇怪问题

环境为AS 4+apache 2.0+php+mysql，最近一段时间经常apache会无规律地挂掉，但手工重启立刻又可以提供服务，下面是error_log记录的出错信息，请各位帮我想想办法解决这个问题：

注：xxnet.cn是网站的域名，被我替换了

[Sun Dec 24 13:44:11 2006] [error] [client 220.181.19.178] File does not exist: /usr/local/apache/htdocs/resource
[Sun Dec 24 13:44:15 2006] [warn] child process 11853 still did not exit, sending a SIGTERM
[Sun Dec 24 13:44:17 2006] [warn] child process 11853 still did not exit, sending a SIGTERM
[Sun Dec 24 13:44:19 2006] [warn] child process 11853 still did not exit, sending a SIGTERM
[Sun Dec 24 13:44:21 2006] [error] child process 11853 still did not exit, sending a SIGKILL
[Sun Dec 24 13:44:22 2006] [notice] SIGHUP received.  Attempting to restart
[Sun Dec 24 13:44:23 2006] [notice] Digest: generating secret for digest authentication ...
[Sun Dec 24 13:44:23 2006] [notice] Digest: done
[Sun Dec 24 13:44:49 2006] [alert] (EAI 2)Name or service not known: mod_unique_id: unable to find IPv4 address of "xxnet.cn"
Configuration Failed

/etc/hosts
里面加上：
服务器ip xxnet.cn