Yesterday I shutdown my ubuntu 10.04 server running zimbra 7.1.2 because I had to restart the VM host, which is Windows 7. When I started my ubuntu server I saw "task java blocked for more than 120 seconds" messages and it was frozen. I shutdown the Ubuntu VM by stopping the VM. On restart I was getting errors about httpd.pid and "zimbra could not open pid lock cyrus-sasl". Google searches suggested to remove/rename the files and restart zimbra, which fixed it. Being a ubuntu/zimbra newguy I am interested on what happened, how to avoid it and what do those files do?