Sunday, May 10, 2009

My struggle with VMWare server

Like so many of my fellow IT collegues I run VMWare server on my laptop to do tests. I had my laptop scratched by our internal IT a couple of days ago and when I installed the latest VMWare Server (2.0.1) it worked fine and suddenly I got this.

The first thing I got was this error message:
Failed to Connect
The connection was refused when attempting to contact :8333.
Though the site seems valid, the browser was unable to establish a connection.
* Could the site be temporarily unavailable? Try again later.
* Are you unable to browse other sites? Check the computer's network connection.
* Is your computer or network protected by a firewall or proxy? Incorrect settings
can interfere with Web browsing.

When I had a look at the services I noticed that the VMWare Host Agent service was down.
I tried to start it but no luck. It stayed down. In the Windows System Event log mentioned
"The VMware Host Agent service terminated with service-specific error 4294967295 (0xFFFFFFFF)." I googled it and found in the VM communities that my datastores.xml file was corrupted.

The way to repair this is to go to "C:\Documents and Settings\All Users\Application Data\VMware\VMware Server\hostd" and rename the old datastores.xml and make a copy of the datastores.xml.default and rename that copy to datastores.xml. I started the service and the service started without any problem.

But I was still not at the end of the tunnel. The error message in my browser was still the same. Next thing I tried was to change the computername by localhost. I got a message to tell me the SSL certificate was not installed. So I installed it and it loaded the login interface :).

The situation is now that I can open it through localhost but not via computername nor through the IP-address. Interestingly enough I tried the loopback IP address and got the message again that the certificate was not installed. I added my hostname to the hosts file with no success. So I wonder how the name resolution is done, I thought the first place where Windows looks to resolve a name is in the hosts file. I talked to a VMWare specialist at my job and although he is only familiar with ESX he thinks that I should look at the implementation of the tomcat. If anybody has a clue about this, please contact me.

On my linux box at home I run the same VMWare server and there I did not have the same problem since I made the shortcut in my browser myself and pointed it to localhost :). I guess there are just some bugs in it.

Tuesday, May 5, 2009

Quick format or regular format?

Yesterday I worked side by side with a collegue specialized in storage (SAN) and when he presented the disks to the Windows Operating System I mounted the drives and told Windows to start formating.

After a while my collegue asked me how far the formatting was and when I said X %, he told me I should have taken quick format to go quicker. Always willing to learn something I asked him what the actual difference is. The guy said that when you do a quick format, you actually don't do a format but the formatting will be done when you need the space. Quick format only defines the beginning and the end of the partition. Whereas the full format does a real format and goes through every sector on the partition. By doing this you will gain I/O performance my storage specialist said. This is interesting since one of the classic bottlenecks is the disk I/O.

So, OK it takes time to format 300GB but if I gain some I/O performance and in the best of cases I can do it at night while sleeping it is worth I think considering it.