When is iSCSI Preferable to a Mapped-Network Drive?
What’s the difference between iSCSI vs. Mapped-Network Drive? As an IT pro, when you find yourself tasked with the crucial decision of selecting a storage protocol for a project, the choice between iSCSI and mapped network can be make-or-break. Block level storage via iSCSI allows you to configure the raw space to meet your needs and is attractive when you need massive amounts of configurable storage space. Mapped network protocols can be flexible and versatile, just as iSCSI Storage-Area Network (SAN), but block level storage isn’t a fit for every application or data storage situation.
For mission-critical deployments, choosing between iSCSI and Network Attached Storage (NAS) is critical. For smaller companies that don’t have a large IT department or aren’t outsourcing their IT functionality, iSCSI protocols might be too complex to manage compared to mapped networks. If you’ve no experience administering block storage devices, it might be a challenge to get over the learning curve.
To administer an iSCSI set up, you must be equipped to effectively manage storage communications infrastructure, effectively manage RAID controller levels, effectively track drive performance to guarantee performance needs are met and manage and assign storage to each server. Conversely, managing a mapped network is comparatively simple plus Network Attached Storage (NAS) is typically more cost-effective than an iSCSI set-up.
In a perfect world, given no budgetary constraints and assuming no management or knowledge gaps, when would you choose iSCSI over mapped network or vice-versa?
The performance proclivities of an application might push you to iSCSI over NAS, or the reverse. Slower response times than anticipated might indicate you’d be better served by changing file storage protocols. When you’re looking to upgrade an application or make wholesale changes, such as migrating from one accounting package to another, researching performance based on storage protocol is wise.
In general, when looking at use case, iSCSI block-level shared storage is preferable (or mandatory) with:
- Microsoft Exchange as it does not allow file level or network-based storage, only block level storage.
- Applications that rely on databases, and clustered databases in particular.
- Target boot since you can rapidly boot up to 256 computers off one OS image and realize a greater than 90% storage savings by eliminating duplicate OS
images in favor of one master OS image.
- VMware even though it can use file level storage but is more commonly and effectively deployed via block level storage.
WORM Storage for Compliance
Compliance is increasingly a concern, particularly for larger firms or those in industries where archival storage is both critical and mandatory such as in the financial, legal, non-profit, and brokerage space. iSCSI setups offer cheaper long-term, high-volume storage solutions. WORM compliance mandates offsite redundancy, data security and data protection and is supported only at the file-level so is incompatible with iSCSI block-level storage.
iSCSI block storage is preferable as shared storage for a failover cluster (group of independent computers working together to increase scalability of clustered roles) in most cases.
Speed Versus Capacity
Two facets to consider are capacity and performance. If you have a great quantity of users that require screaming fast performance from your file storage or if the application itself demands it, then block level storage is more configurable for this purpose. File-level storage can perform well, depending on the application, but is better known for high-capacity than high-performance depending on the circumstances.
Ease of Use
File-level storage servers are easier to configure and use than block-level. You will have to go through additional steps to establish protocols for permissions, authentication, and back-ups, but these aren’t difficult to accomplish. A configuration tool can help you get everything set up to allow the access and security that you require. Mass file storage and VMware hosts to access storage can both be accomplished in a more cost-effective manner with mapped network file storage.
Depending on your needs, you may be best served by iSCSI storage, mapped network, or, more likely, a hybrid system that allows greater flexibility and scalability, particularly if you have a diverse array of applications running across your enterprise. When you’re ready to expand or upgrade your storage, QSAN’s XCube products offer the best of both worlds.
XCubeSAN and XCubeNAS devices are versatile hybrid storage device for complex network environments with self-encrypting (SED) technology to protect your data. Features include data deduplication functionality, SSD-ready, offer SSD caching, high IOPS, and dual controllers. Our XCubeSAN series supports iSCSI protocols while our XCubeNAS series are perfect for mapped network storage and WORM compliance.