What are VSAN's

Hi Karthik,

Not sure whether you have already received the required information you were looking for. However, since there was no reply to this thread here, my little effort to help you out.

Are you referring to VSAN in terms of Cisco Switches? Typically, VSAN will be meant for Virtual SAN - and if you are familiar with VLAN (Virtual LAN) fundamentals - it is very similar to it. VSAN was designed by Cisco modeled after their VLAN concept - but later it has been widely used and deployed in a complex SAN technology.

In a Storage Area Network - where all devices are interconnected in a switched (fabric) environment, you may create a virtual fabric out of the same physical SAN - the devices in a VSAN will be restricted to see and talk to the other devices in the same VSAN.

By definition, A virtual storage area network (VSAN) is a collection of ports from a set of connected Fibre Channel Switches, that form a virtual fabric. Ports within a single switch can be partitioned into multiple VSANs, despite sharing hardware resources. Conversely, multiple switches can join a number of ports to form a single VSAN.

Based on what exactly you are looking for and what you plan on doing - you may find a number of technical documents and manuals from different vendors.

Happy to be of any little help here,

Thanks,
Sandip

VSAN is something like logical splitting of a physical fabric. It is a collection of ports from a set of connected Fibre Channel switches, that form a virtual fabric.

Hello Karthik,

VSANs are similar in many ways to VLANs. MDS-series switches allow physical switches to be carved into several virtual fabrics called VSANs (Virtual SANS). VSANs have the following features:

• Physical Topology - A physical topology may be partitioned into one or more logical fabrics called VSANs. Each VSAN has Fabric services and Domain Identifiers the same as if they were each a single switch(domain).
  
• Zoning - Zoning is created and assigned per VSAN.  Each VSAN (except the isolated VSAN) may have one active zoneset configured at a time.
  
• Ports - VSAN membership is assigned on a port-by-port basis.  By default each port belongs to the default VSAN. VSAN membership can be edited through the CLI or GUI.
  

When creating VSANs, multiple switches are not required, a VSAN can be created on one switch, however the use of TE_Ports allows VSAN traffic to flow across ISLs in the fabric. VSANS can be created using the CLI, Fabric Manager or Device Manager. The major difference is that with the Fabric Manager GUI is that VSAN can be created on all switches in one step.  With the CLI or Device Manager, VSANs must be created in each switch separately.

• Default VSAN - The factory settings for the MDS-Series have only the default VSAN (VSAN 1) enabled and all ports are assigned to the default VSAN.  If more than  one VSAN is not needed, use this default VSAN as the implicit parameter during configuration.  If no VSANs are configured, all devices in the fabric are considered part of the default VSAN.  Note that VSAN 1 cannot be deleted.  It can, however, be suspended.
  
• Isolated VSAN - VSAN 4094 is the isolated VSAN.  All non-trunking ports are transferred to this VSAN when the VSAN to which they belong is deleted. This avoids an implicit transfer of ports to the default VSAN or to another configured VSAN.  All ports in the deleted VSAN are isolated (disabled). Ports may be configured into VSAN 4094. However, when a port is moved to VSAN 4094, that port is immediately isolated.
  

This information is from the EMC SAN Management course. more information on VSANs can be found in the Advanced SAN Implementation course (for implementers) and the Advanced SAN Design course (for architects) available through the EMC education website http://education.emc.com

Hope this helps,

   Mike Warner
   Senior Technical Education Consultant
   EMC Education Services
   EMC² Corporation
   55 Constitution Blvd.
   Franklin, Massachusetts 02038

Thanks Sandip..

That was definitely helpful.. and simple..

Cheers..

Karthik

VSAN  (virtual storage area network) is a collection of ports from a connected Fibre Channel switches, that form a virtual fabric. Ports within a single switch can be partitioned into multiple VSANs, despite sharing hardware resources. Multiple switches can join a number of ports to create a single VSAN. VSANs can also be configured separately and independently.

VSAN is the feature of CISCO MDS Switches, Brocade switches have the same feature called LSAN.