Currently we have one 600GB LUN used for writecache drives in our VM's the storage is shared over a pool consisting of 4 XenServers and 10 VM's. A SAN is block-based storage, leveraging a high-speed architecture that connects servers to their logical disk units (LUNs). Since only the File Server computer has direct access to the physical disk, all servers computers connecting to these disks use the same File System (The File System of the NAS). In good old "copper" SCSI days, mapping a device on a port of the storage was the act that let the host see the device since each port of the storage was connected to a single host with a copper cable. SAN and NAS each have their own benefits and trade-offs. This tool uses JavaScript and much of it will not work correctly without it enabled. [1]:11 Potentially the data storage capacity that can be accessed by a single server through a SAN is infinite, and this storage capacity may also be accessible by other servers. Copyright © 2017 VMware, Inc. All rights reserved. Switches have the advantage over hubs that they allow all attached devices to communicate simultaneously, as a switch provides a dedicated link to connect all its ports with one another. Virtualizing Business Critical Applications. The ports of storage devices often have a WWN starting with 5, while the bus adapters of servers start with 10 or 21. Over-provisioning can be used to provide additional capacity to compensate for peak network traffic loads. Im trying to figure out if it would be better for performance if we split up in smaller volumes to optimize IO to the LUN. Analysis Services workload) I don't know if our SAN admin uses one partition per LUN. [1]:174 SAN management software will collect management data from all storage devices in the storage layer, including info on read and write failure, storage capacity bottlenecks and failure of storage devices. LUN expansion with Microsoft cluster server.
[1]:177 Management software applications are also available to configure SAN storage devices, allowing, for example, the configuration of zones and logical unit numbers (LUNs). Storage array usually have large storage capacity, we don't want one server to use the whole thing, so we divide it into logical units (LUN) is actually Logical Unit Number, so we get storage sliced into usable chunks, and present it to the server. Let us know, Discover What You Can Do with NetApp Cloud Services, Simplify and Automate Virtualized Workloads, Continuous Integration/Continuous Delivery (CI/CD) ›, Active IQ Predictive Analytics and Support, Performance Benefits of NVMe over Fibre Channel, Why NVMe Over Fibre Channel is Needed Today, Internet Small Computer System Interface (iSCSI), Non-Volatile Memory Express over Fibre Channel (FC-NVMe), Accelerate your SAN solutions with NetApp’s leading performance, Leverage the best cloud-connected infrastructure to flexibly move and protect your data across your hybrid cloud environment, Deliver the high availability (greater than six nines) that your business applications require.
Configuration C2 (iScsi with 1 Frs directory). Basic device management for SANs can also be achieved through the Storage Management Interface Specification (SMI-S), were CIM objects and processes are registered in a directory. [3]:34 When SANs were first built, Fibre Channel had to be implemented over copper cables, these days multimode optical fibre cables are used in SANs. A particular server, or a group of servers, may, for example, be only given access to a particular part of the SAN storage layer, in the form of LUNs. [2]:16–17, DAS was the first network storage system and is still widely used where data storage requirements are not very high. Software applications and subsystems can then draw on this directory. The simplest configuration : you have only one FRs (Input/Output) server. NFS datastores comprise another part of NAS data. SAS evolved from SCSI direct-attached storage. Using SAN storage QoS is in contrast to using disk over-provisioning in a SAN environment. This is not a fast method but it works, Configuration C1 (SAN with 1 Frs directory). Configuration B : 1 BO cluster (at least 2 computers) with only 1 FRS (Input/Output) server Enabled and Started, One FRS (Input/Output) server is Enabled and started, one FRS (Input/Output) server is Enabled and Stopped. LUNs are key to disk array configuration because disks are typically defined in sets of RAID groups to protect against failure; however, those RAID … A SAN is block-based storage, leveraging a high-speed architecture that connects servers to their logical disk units (LUNs). SAN expert Chris Poelker compares connecting a SAN with wavelength cabling and dark fiber and discusses the pros and cons of each. For instance, if you serve your SAN data using Fibre Channel Protocol, you have Fibre Channel switches and HBAs (host-based adapters) dedicated for this traffic. [3]:48 Every storage device, or even partition on that storage device, has a logical unit number (LUN) assigned to it. SAS and SATA devices can be networked using SAS Expanders.
By definition a SAN is not able to manage the lock / unlock of your FRs files.
[2]:22 In a NAS architecture data is transferred using the TCP and IP protocols over Ethernet.
I create my SAN vDisks and just one LUN per vDisk and then create mutiple VMDK files within that LUN for each individual datastore/drive for each VM in vSphere.