NAS vs SAN - Network Attached Storage vs Storage Area Network

What is the difference between a NAS (network attached storage) and a SAN (storage area network)?

What is a NAS?
What is a Storage Area Network?

#NAS #SAN #NETWORKATTACHEDSTORAGE

[ZenDragonJP]

I am a manager of a data center and love to ask this question on interviews. Enterprise NAS appliances are designed to be highly available, with redundant controllers, with dual power supplies, and dual network links (often arranged in LACP teams). NAS serves file systems (in the form of shared folders) to end points (typically end user devices) on a corporate network (the LAN). Now, if you want to use NAS for a non traditional workload (such as an NFS export for VMWare data stores), you'd typically devote switches to that use case to avoid the contention with typical end user LAN traffic (when using the same switches as your LAN) described in the video. The reason SAN is marketed as a faster technology has less to do with bandwidth of the different networks (there are 25, 40 and 100 Gb/s ethernet links as well) and more to do with the fundamental differences between NAS and SAN . SANs share raw disk "blocks" (from a storage "target") to endpoints (typically other servers, or storage initiators) commonly in the form of logical disks (LUNs). Block transactions are faster than filesystem transactions because they operate at a lower level and are overall more simple, so block transactions require less overhead. Filesystem transactions occur "on top of" block transactions. Meaning a simple file copy must be process at the file system level as well as at the block level. The filesystem (which is what the NAS serves) in a SAN environment is handled at each independent endpoint, so the SAN target doesn't have to do any of the file system overhead processing, such as tracking and updating filesystem metadata. The filesystem processing overhead is thereby distributed across each endpoint/server. But if you have a single storage target, you could be bottlenecked at the block level if you have several busy servers attached. If you are trying to compare a NAS to a SAN, realize you are comparing apples to oranges. If you want to make apple pie, the apples are probably a better ingredient. But if you want to make orange juice, you'll want to go with oranges. Similarly NAS is designed for some use cases, and SAN for others. Generally speaking - are you trying to share files with end users (NAS), or are you trying to share disks to servers (SAN)?

[cameroncowles]

I love how the simple nature of these videos never fails to attract the "Well, actually" tech-geniuses, that then proceed to spew a couple paragraphs of tech-jargon in order to show how smart they are.

[mikeshinoda]

Dude, this is the BEST video I can find on the Internet that explains NAS SAN clearly for a beginner. So many vids are focusing on all those terminologies which is a nightmare for the audience. Yours is straightforward and comes from real-world..

[AllHailAkemi]

I don't know how you manage to create videos about the exact things I need to know about. I am extremely thankful for the time you take to make your videos, the animations are fabulous and I can see a lot of time behind. Thank you very much, keep being awesome.

[chromerims]

I came back after several years to this video. I am appreciating how it condenses so well and so much good and correct information into just 4 minutes.
Thank you, PowerCert Animations 👍

[Gurianthe]

I just started working for Pure Storage and I am 100% sure that the trainer used this video to write her training material, literally word by word

[zyzzuschrist]

Dude I can’t tell you enough how much I love these animated videos. You helped me learn binary math

[Alex-bcxe]

I hated Network topics but your videos made me love it

[PlasmaJunkie]

I love how direct and to the point this channel's explanations are. Another great video. Thanks!

[hikgerguy]

Very nice, clear explanation. Good pace and clear voice. Nicely done and much appreciated!

[mort_brain]

You have the greatest videos: simple, yet not primitive, informative, yet not overwhelming.

[jonsku]

Dude. This channel is a very good find for me. It explains many tech-related topics and the animation style is amazing.

[DerekWright]

You are making some incorrect assumptions about these technologies. NAS is a single system dependent upon a traditional layer 3 ip packet switched network and requires a client implementation for presentation. A SAN is a layer 2+ technology that involves a multitude of systems for providing connectivity/switching across the network and presentation appears native to the OS due to encapsulated SCSI payloads. A NAS can be extremely fault tolerant and redundant and a SAN can be poorly implemented and unreliable. A SAN can be ethernet or fibre channel (note fibre channel is NOT fibre optics, its a protocol for encapsulation of SCSI frames). While this video IS simple, it is also misleading and neglects some finer details that are worth noting to actually clear confusion and get rid of propagating assumptions.

[atuldpatil]

Exactly how I wanted to know. Simply great explanation in just 4 minutes !

[AHAAAA]

Thanks for your concise, tidy video at the same time with informations enough to grasp the essence of the difference between the systems.

[Jormunguandr]

SAN is fun to play with. Bought some old IBM equipment, pcie SAS controller cards and cables from ebay. Used two debian servers with 40Gbps infiniband. 60 hours spent. worth it :D

[pummyy]

Can't explain simpler than this. Great video for anyone who wants to understand the basics.

[scottscott]

Excellent. Very well illustrated with clear, simple explanations. Thank you.

[anthonyholleran]

Out of plenty of IT traning videos I have seen or watched, your training videos, Sir, are right on point and your teaching style and animations, pictures, and explanations are comprehensive enough for a six year old to assimilate and understand! Please do not stop making these videos, keep 'em coming! Thank you Sir! ~Respectfully - Anthony

[tokyoneko]

Currently studying for my Network+ and this video was very helpful in explaining the differences between the two! Thanks for putting this kind of content out!