Storage Explained: NFS:FCoE:SAN:FC

Recently while attending yet another storage course I came accross a reasonably common question...
Something that most storage administrators struggled with at some stage...

Why would I use NFS on my Storage Array?

Warning: This might get a bit technical, but bear with me.

This seemingly simple question has a lot of factors to consider.
First thing to keep in mind is that NFS is a network protocol, thus adding further overhead to your stack. The only true storage protocol is SCSI, all storage is contained in this protocol for system purposes. So, keeping that in mind... The positive side to NFS is that face that it can run over ethernet, which in todays standards can go up to 10Gbps, as opposed to the max of 8Gbps that FC provides, but how does an FC packet compaire to a NFS packet... The payload (data) in your storage packet is contained in SCSI headers (take this as a given). An FC packet encapsulated the whole SCSI packet in another set of headers (the FC headers). When it comes to NFS it changes slightly... Fistly the SCSI packet gets encapsulated into ethernet headers to form the ethernet (layer 2)packet, this packet now gets encapsulated into IP headers to form the IP (layer3) packet, which allows routing to take place. After all of this the IP packet (which now contains the ethernet packet, which contains the SCSI packet, which contains the data) gets yet another set of headers... The layer4 headers for NFS. This is a lot of overhead! So in the end your performance gain is probably closer to 0.

Lets look at other factors...
SAN switching, and HBA's are quite expensive, and can cost a bundle, but so does a propper 10Gbps network switch, and propper 10Gbps NICs and SFPs. Also NFS is usually a licensed feature by your storage provider. So these costs in the real world would definately be the deciding factor here.

Which brings us to the alternative... FCoE. I've posted a write up on this in th past, and there's good reason why I prefer this. Note, this is only my opinion. FCoE takes your payload (contained in the SCSI packet), and adds the FC headers to it, and the Ethernet headers. That's it. So eventhough there's more to it than an FC packet it's still a lot lighter than an NFS packet, since you dont need the layer3 and 4 headers. So here the 10Gbps vs 8Gbps really comes to play. Another factor that makes this even more appealing is that you can run your normal network, and your storage over the same cable, thus saving costs. Downside though is that you need expensive switches for this.

All in all the question really has more to do with what you're planning for your environment than simply weighing up the pros and cons, but keeping all things in mind, and making an informed decision never hurt anyone.

Cloud Computing Explained

Cloud computing is a general term for anything that involves delivering hosted services over the Internet. These services are broadly divided into three categories: Infrastructure-as-a-Service (IaaS), Platform-as-a-Service (PaaS)and Software-as-a-Service (SaaS). The name cloud computing was inspired by the cloud symbol that's often used to represent the Internet in flowcharts and diagrams.

A cloud service has three distinct characteristics that differentiate it from traditional hosting. It is sold on demand, typically by the minute or the hour; it is elastic -- a user can have as much or as little of a service as they want at any given time; and the service is fully managed by the provider (the consumer needs nothing but a personal computer and Internet access). Significant innovations in virtualization and distributed computing, as well as improved access to high-speed Internet and a weak economy, have accelerated interest in cloud computing.

A cloud can be private or public. A public cloud sells services to anyone on the Internet. (Currently, Vodacom Business Services is the largest public cloud provider in Africa.) A private cloud is a proprietary network or a data center that supplies hosted services to a limited number of people. When a service provider uses public cloud resources to create their private cloud, the result is called a virtual private cloud. Private or public, the goal of cloud computing is to provide easy, scalable access to computing resources and IT services.

Infrastructure-as-a-Service like Vodacom Cloud Manager provides virtual server instance API) to start, stop, access and configure their virtual servers and storage. In the enterprise, cloud computing allows a company to pay for only as much capacity as is needed, and bring more online as soon as required. Because this pay-for-what-you-use model resembles the way electricity, fuel and water are consumed, it's sometimes referred to as utility computing.

Platform-as-a-service in the cloud is defined as a set of software and product development tools hosted on the provider's infrastructure. Developers create applications on the provider's platform over the Internet. PaaS providers may use APIs, website portals or gateway software installed on the customer's computer. Force.com, (an outgrowth of Salesforce.com) and GoogleApps are examples of PaaS. Developers need to know that currently, there are not standards for interoperability or data portability in the cloud. Some providers will not allow software created by their customers to be moved off the provider's platform.

In the software-as-a-service cloud model, the vendor supplies the hardware infrastructure, the software product and interacts with the user through a front-end portal. SaaS is a very broad market. Services can be anything from Web-based email to inventory control and database processing. Because the service provider hosts both the application and the data, the end user is free to use the service from anywhere.

Videos:

http://www.youtube.com/watch?v=ae_DKNwK_ms

http://www.youtube.com/watch?v=eOqlApm73NE

http://www.youtube.com/watch?v=uYGQcmZUTaw&feature=related

FlipIT, lets talk about DaaS...

What is DaaS?
Desktop as a Service (DaaS) is coming, and it's bound to take the ICT market by storm.
Since the early days of VDI (Virtual Desktop Infrastructure) there has been talks about getting this service into the cloud, and leveraging it off the global network that is the Internet. Traditionally this was just a dream, as bandwidth was just too expensive, things have changed, in terms of bandwidth costs, and new protocols, making this far more cost effective.

Why host your desktop in the cloud?


Essentially, DaaS is a Virtual Machine loaded with a Desktop (workstation) Operating System, that is being hosted in a datacenter at an ISP. The Management interface of the environment will have a public IP address, and a Public URL. To access this desktop you will use a Thin-client, which is essentially just a device with Internet connection that has a screen, keyboard and mouse connected to it. The image below is an example.



So you connect to your Windows XP (or Windows 7) over the Internet using this Thinclient... Your user experience remains the same, but there are huge benefits... A few examples would be: You can now have as many different "PCs" (with different specs) as you want (One for work, one for the kids, one for your wife, etc), and connect to them via the same Thinclient, determined by login credentials! Also, note these can not be stolen either!!! If someone steals your Thinclient, simply get a new one, your desktops still remain unchanged, and unaffected! Also upgrading to more disk space, more memory, or processing power couldn't be easier... Traditionally you would phone a techie, who would charge for the labor, and part, and then it still took a couple of hours at least to have it done, with this platform upgrading is as easy as phoning the ISP, and requesting, after the phone call you reboot your machine, and it upgraded!!!! Same goes with software, you need a software package, you request it online, log off, and log back on, and it's there, instantly! No more waiting, no more software conflicts, no more expensive technical people!

Unique Partnership between Vodacom Business and NIL.

Vodacom Business is now exploring the DaaS opportunities South Africa has to offer, partnering with Professional Services company NIL, who specialises in Cisco Professional Services, and Virtualization. NIL has developed a unique portal for provisioning onto the VDI platform, and together with their years of network experience, they have developed a solution to the tedious, and complex VDI provisioning process.

The product is called FlipIT, and it's designed to literally Flip IT and traditional ways of doing things around. It is fully multitenated, and integrates into every aspect of provisioning, from the network switches, to the firewalls, and storage arrays. By the click of a button you create a hosted company, while in the background VLANs are added, firewall rules are implemented, Fileservers, and LDAP servers are created, and users are loaded! All of this in the span of just 15 minutes, and you have a working IT environment, with Internet, an IP phone and an Email address, and the best part is that it's securely hosted, and managed in the cloud!!!

I had the fortunate experience of being involved with this project from the start, and it's now coming to completion with production rollout expected early in Q2 2011. Working with NIL has been a great experience, they are a very professional company with rock solid technical skills to back them. There were a number of successfully proof-of-concepts conducted by major companies, and every single one were satisfied, and excited about this new venture. What they liked most was the seamless, and effortless manner in which software could be added, and removed from the desktop through the user friendly portal. The fact that using the new PCoIP protocol makes this work perfectly even over a 3G connection is also a major plus point. Another very exciting feature is the integrated monitoring tool (NIL Monitor), which monitors everything, but this I would have to write about separately, as in itself this is a truly brilliant product on its own.

PCoIP?

As the abbreviation states... PCoIP (PC over Internet Protocol), this new revolutionary protocol was designed to be ably to run your PC (Virtual Desktop in this case) over an Internet connection. It is a very compressed protocol that is designed to only send through the changed pixels on your screen over the network as opposed to traditional RDP which sends updates on the whole desktop through the link, by doing this PCoIP massively reduces the amount of bandwidth needed for desktop streaming, and this makes DaaS possible over cloud computing. With new developments on mobile clients such as Wyse's Pocketcloud, you can now even connect to your desktop from a cellphone.

In summary:

DaaS is going to be big, and it's coming. Basically you can connect to your hosted Virtual Desktop from just about any device with an Internet connection, be it a ThinClient, Cellphone, iPad, laptop, or an Internet cafe, the sky is the limit, and it all sits securely, and safely in the cloud, meaning it can't break, get lost, of get stolen!

Additional resources (Videos):

Cloud Computing Explained

Wyse Pocket Cloud

Technology Progression

FCoE anyone? Cisco Nexus 5000, FCoE

There's quite a hype around the new Cisco Nexus 5000 series switches...


Packed full of quite interesting new features like FCoE (Fibre Channel over Ethernet), VPC (Virtual Port Channel), NPV (N-Port Vitalisation) support, etc there is little wonder why!

I want to do a quick rundown of FCoE, as in my mind this is a great and useful feature!
 
Firstly, what is FCoE?
To understand this concept we'll have understand what makes up a FCoE frame...
 

Note that a basic frame/packet consists of 2 things, namely the payload (data), and the header (addressing, checksum, etc).

In this image note that the data portion is referred to as the "Payload", and the rest is just protocol headers.

The Fibre Channel Payload is encapsulated in the FC (Fibre Channel) header this makes up the FC frame. The whole FC frame is encapsulated in a FCoE header, thus the FC frame becomes the Payload in a FCoE frame, and gets a new set of headers around it. Last step is basically where the whole FCoE frame gets encapsulated in yet another set of headers, the Ethernet headers.

In lamens terms the packets being sent from the switch is ethernet packets, but instead of sending ethernet data it sends encapsulated FC data in the payload.

Ehternet and FC traffic differs in the type of data it's used for. Essentially an FC frame is just a SCSI frame encapsulated in an FC header. So basicall FC traffic is data, nomally sent from a SAN (Storage Area Network) switch... It's DATA. Whereas ethernet is as we all know network data... Connecting the the web via network for instance is ethernet.

The Nexus 5000 is one of only a few switches in the market that bridged the gap between Ethernet and FC, using FCoE we are now able to have our SAN connectivity and our Ethernet connectivity through 1 (one) single network port known as a CNA (Converged Network Adaptor). This is typically 10 Gigabit Ethernet connectivity, and looks similar to a FC port, but the card, port and cable does differ from FC.

Config...

The nicest thing about this technology is that Cisco made the config quite easy!

Just a few quick steps, and you're off!

The first step in the process is to enable the FCoE feature.

nex01-lab# conf t

Enter configuration commands, one per line. End with CNTL/Z.
nex01-lab(config)# feature fcoe
FC license checked out successfully
fc_plugin extracted successfully
FC plugin loaded successfully
FCoE manager enabled successfully
FC enabled on all modules successfully
nex01-lab(config)#

Now create your VSAN
nex01-lab(config)# vsan database
nex01-lab(config-vsan-db)# vsan 3777 name FCoE
nex01-lab(config-vsan-db)# exit
nex01-lab(config)#


Next step is to create your FCoE VLAN (to correspond the your VSAN)
nex01-lab(config)#
nex01-lab(config)# vlan 3777
nex01-lab(config-vlan)#
 
Next step is where you enable FCoE for the VLAN and map it to a VSAN
nex01-lab(config-vlan)#
nex01-lab(config-vlan)# fcoe vsan 3777
nex01-lab(config-vlan)#

Now you create a VFC (Virtual Fibre Channel) port, and bind it to a physical interface.
nex01-lab(config)# inter vfc 1
nex01-lab(config-if)# bind interface ethernet 1/10
nex01-lab(config-if)# no shutdown
nex01-lab(config-if)# exit
nex01-lab(config)#

Now you have to add your VFC to the VSAN database.
nex01-lab(config)#
nex01-lab(config)# vsan database
nex01-lab(config-vsan-db)# vsan 3777 interface vfc 1
nex01-lab(config-vsan-db)# exit
nex01-lab(config)#

Easy as that!
Now verify connectivity with the following commands:
show interface brief
show flogi database
show fcns database

If all is well your ports should be up and connected!

I hope this has been informative.

Virtualisation is taking over the IT world!

It's been a long time coming, but Virtualisation is in full swing in South Africa now.
It's about time server, and desktop virtualisation kicked off!
The networking guys have been boasting virtualisation for years now in terms of VPN (Virtual Private Network), VLANs (Virtual Local Area Networks), and switch contexts. Now finally server and desktop virtualisation is getting into maturity in South Africa.

With server virtualisation flavours like VirtualBox (free), Zen, MS HyperV, and the market leaders VMware we are sure to see lots of interesting new ventures.

I recently had the fortune of creating a VDi solution for Vodacom Business using VMware View, on Cisco UCS blades connected to a Cisco Nexus 5k ethernet switch, and an MDS9513 Firbre switch, and must admit, it's the most fun I had in ages, having to configure Fibre Channel over Ethernet, dynamic WWNs and MACs.

Cisco is definitely way ahead of the competitors with regards to solutions around Virtualisation technology. All their products fit together seamlessly, and the only downside one might argue is the pricetag. With Cisco's Unified Computing Solutions server redundancy is the norm where everything is dynamically configurable, including SID, MAC, and WWN, this together with boot from SAN the hardware almost becomes irrelevant. If you find a server blade has failed, all you need to do is swap it with a new one, assign the service profile, and you're up and running again... A matter of minutes! Even better than that though... Using a VMware HA cluster means that your server (virtual... of course) flips over to the other server blades while maintenance happens, meaning ZERO... That's right... NO DOWNTIME WHATSOEVER!!! Now in my mind that's a world class solution!

Like I said... If you're in IT, you might as well start skilling up on this, as it's coming to take over the world!

The day it all started.

Today, after having an extremely slow.... Boring day at work, I decided to start this blog.
I'm not planning too much for this, all I really want to try and get out of it, is a place to blow off steam, and maybe every now and then post something interesting or funny.