From the many posts around the Internet and our own experience worker_processes value is recommended to be set to the number of cores your server has.
For example, if you have two dual core CPU you should set worker_processes 4;

Original worker_processes help from Nginx page:

worker_processes 4;

nginx has the ability to use more than one worker process for several reasons:

1. to use SMP
2. to decrease latency when workers blockend on disk I/O
3. to limit number of connections per process when select()/poll() is used

The worker_processes and worker_connections from the event sections allows

… Read the rest of this entry »

Are you looking forward to balance HTTP or HTTPS traffic to multiple back-end servers? Nginx is one of the best choices – it’s very lightweight, requires less resources and it’s completely free.

You need to compile the nginx (there are many resources and howto’s) and add the following lines to your nginx.conf file:

upstream webcluster {
server 10.10.10.1;
server 10.10.10.2
server 10.10.10.3;
}

location / {
proxy_pass http://webcluster;
break;
}

Where 10.10.10.1, 10.10.10.2, 10.10.10.3 are the back-end web servers located in internal network defined in upstream settings above. The location /… Read the rest of this entry »

On November 19, 2009 Vmware has released a new and updated list of new guest OS support and it’s been great news! Now vSphere 4.0 U1 fully supports Windows Server 2008 R2 Enterprise, Standard, Datacenter, and Web Server Editions.

The following new guest OS support has been added with vSphere 4.0 U1 (Update 1):

Windows 7 Enterprise, Professional, Ultimate and Home Premium Editions
Ubuntu 9.10 Server and Desktop
Debian 5.0.1, 5.0.2, and 5.0.3
FreeBSD 7.2

Good job Vmware!

Vsphere is a perfect choice for consolidating servers and to better utilize the hardware. We currently use HP DL585 G5 AMD powered workhorses powered by Vsphere 4.0 ESXi and Virtual Center reports hardware alert (under the tab Hardware Status):

1 Warning: System Board 8 ProcHot out of 111 sensors.

In vSphere 3.5 we easily solved the problem by installing HP ESXi CIM providers for Vmware 3.5. I went to the HP site and found HP ESXi providers for vSphere 4 (file name: hp-esxi4.0uX-bundle-1.1.zip). I downloaded and used vihostupdate.pl to update the server. Remember that you need to put it in… Read the rest of this entry »

Not the first time  I see the following error:  An error occurred during operation: CheckAndAllocateCache when performing fresh Vsphere host update using Host Update Utility. You should ignore the error and rescan the host and patch the host again. Sometimes it works with the second try, sometimes, you have to reboot the box and it will work.

A complete log is attached below:

Patching 10.10.0.2

The patch operation has failed with this error: An error occurred during operation: CheckAndAllocateCache

Patching 10.10.0.2

Start uploading files to host

Metadata and binaries have been successfully uploaded

Scanning the host completed

Start installing patches

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Quite a few folks are running Vmware Vsphere behind the corporate firewalls. We do the same and experienced some problems with Host update utility.

It was quite hard to figure out how to specify the proxy settings so that our Host Update utility can easily check Vmware update servers (for folks who want to open direct access the update server name is hostupdate.vmware.com ) for latest patches.  So we finally figured it out and here are the necessary steps:

Open the VIUpdate folder (in our case: C:Program FilesVMwareInfrastructureVIUpdate 4.0 ) and find file named settings.conf

Open it in text editor… Read the rest of this entry »

It’s been very recommended to upgrade BIOS 4 to BIOS  7 if you are migrating your Virtual Infrastructure 3.5 servers to Vsphere 4. You will experience much better performance using Vsphere 4 and don’t forget to upgrade BIOS. You can do it by shutting down virtual machine and right-click the mouse on the machine name in the inventory. You will notice a new menu appearing “Upgrade virtual hardware”. You can click it and upgrade BIOS in a few seconds, BUT REMEMBER TO TAKE A SNAPSHOT before doing it or there is no way to return the virtual BIOS to version… Read the rest of this entry »