Minimum H/W requirements for VMware vCenter Server 4.x and 5.x

VMware vCenter Server 4.x

Hardware	Requirement
Processor	Intel or AMD x86 (64-bit if installing vCenter Server 4.1) processor with two or more logical cores, each with a speed of 2GHz.
Memory	3GB RAM. RAM requirements may be higher if your database runs on the same machine. VMware VirtualCenter Management WebServices requires 128Mb to 1.5GB of memory which is allocated at startup.
Disk storage	2GB. Disk requirements may be higher if your database runs on the same machine. Microsoft SQL Server 2005 Express requires up to 2GB free disk space to decompress the installation archive.
Networking	1Gbit recommended

VMware vCenter Server 5.x

vSphere 5.1 introduced the vCenter Single Sign-On (SSO) component as part of the vCenter Server management infrastructure. This change affects vCenter Server installation. Authentication by vCenter Single Sign-On makes the VMware cloud infrastructure platform more secure by allowing the vSphere software components to communicate with each other through a secure token exchange mechanism.

Let us see the different parameters required for the installation of VMware vCenter Server

Minimum hardware requirements for vCenter Server

Hardware	Requirement
CPU	Two 64-bit CPUs or one 64-bit dual-core processor.
Processor	2.0GHz or faster Intel 64 or AMD 64 processor. Processor requirements might be higher if the database runs on the same machine. NOTE: The Itanium (IA64) processor is not supported.
Memory	The amount of memory needed depends on your vCenter Server configuration. If vCenter Server is installed on a different host machine than vCenter Single Sign On and vCenter Inventory Service, 4GB of RAM are required. If vCenter Server, vCenter Single Sign On and vCenter Inventory Service are installed on the same host machine (as with vCenter Simple Install), 10GB of RAM are required. NOTE: Memory requirements are higher if the vCenter Server database or vCenter Single Sign On database runs on the same machine as vCenter Server.
Disk storage	The amount of disk storage needed for the vCenter Server installation depends on your vCenter Server configuration. If vCenter Server is installed on a different host machine than vCenter Single Sign On and vCenter Inventory Service, 4GB are required. If vCenter Server, SSO, and vCenter Inventory Service are installed on the same host machine (as with vCenter Simple Install), at least 40-60GB of free disk space are required after installation, depending on the size of your inventory. 100GB are recommended, to allow for future growth of your inventory.
Microsoft SQL Server 2008 R2 Express disk	Up to 2GB free disk space to decompress the installation archive. Approximately 1.5GB of these files are deleted after the installation is complete.
Network speed	1Gbit connection recommended.

System recommendations for performance based on deployment size

Medium deployment of up to 50 hosts and 500 powered-on virtual machines

Product	Cores	Memory	Disk
vCenter Server	2	4GB	5GB

Large deployment of up to 300 hosts and 3,000 powered-on virtual machines

Product	Cores	Memory	Disk
vCenter Server	4	8GB	10GB

Extra-large deployment of up to 1,000 hosts and 10,000 powered-on virtual machines

Product	Cores	Memory	Disk
vCenter Server	8	16GB	10GB

Hardware requirements for vSphere Web Client server component

Hardware	Requirement
Memory	At least 2GB. of which 1GB is for the Java heap and 1GB for The resident code The stack for Java threads Global/bss segments for the Java process
CPU	2.00 GHz processor with at least 2 or more cores
Disk storage	At least 2GB free disk space
Networking	1Gbit recommended

Hardware requirements for VMware vCenter Server Appliance

Hardware	Requirement
Disk storage on the host machine	The vCenter Server Appliance requires at least 7GB of disk space, and is limited to a maximum size of 80GB. The vCenter Server Appliance can be deployed with thin-provisioned virtual disks that can grow to the maximum size of 80GB. NOTE: If the host machine does not have enough free disk space to accommodate the growth of the vCenter Server Appliance virtual disks, vCenter Server might cease operation, and you will not be able to manage your vSphere environment.
Memory in the VMware vCenter Server Appliance	Very small inventory (10 or fewer hosts, 100 or fewer vms): at least 4GB. Small inventory (10-100 hosts or 100-1000 virtual machines): at least 8GB. Medium inventory (100-400 hosts or 1000-4000 virtual machines): at least 16GB. Large inventory (More than 400 hosts or 4000 virtual machines): at least 24GB.

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