Recently one of our web servers httpd stopped working and I haven't been able to find the problem. Today I sat down and went through every directory in the httpd.conf and have found an issue. the /var/run/httpd.pid is missing from the folder. All other files are there and seem to be fine. I cannot create a new file with the same name in vi and I have no idea what could have caused this. I imagine it was caused by a cold reboot at some stage as no other extraordinary processes have been run on this server at the time it went down. I am running CentOS 3. How can I reinstate this file?