© Al Taylor 26th April 2013

Getting eCommerece strategy right has never been more challenging. Customers expect every website they visit to be as fast as Google, if the prize is worth fighting for then they may hang about (London 2012 tickets anyone?) but for online consumers, time matters.

For obvious reasons, no one really knows how much online trade is lost in ‘checkout dropout’ – the point where a potential customer fills their basket but the checkout takes so long to process they can’t be bothered to wait any longer and leave without completing the purchase. I’ve done it, maybe you have too. All the time, effort and money getting visitors to the site is wasted, so there’s always a balancing act of capacity over budget in the back of every decision - too much capacity could lead to trouble with massive costs crippling the business, not enough capacity is lost revenue which can have similar consequences.

Christmas is the obvious time of the year for many online retailers but the same applies for all organisations with seasonal peaks in traffic - 9 or so months of steady volumes of visits to the site with a spike around peak time that all the infrastructure needs to be provisioned for.

The ability to increase capacity isn’t new but rather than adding more appliances to manage the additional traffic, licence key upgrades to existing appliances provide an interesting alternative. The ability to take a 10Mbps virtual appliance up to 200Mbps or a 2Gb hardware appliance up to 6Gb with a licence key can keep the costs in check during steady business growth but there’s still the problem of spiky traffic which is exactly where the 90 day burst licence comes in.

NetScaler burst licences allow smaller appliances to be provisioned throughout the quite times of the year but at the point where things start to get busy, a capacity increase can be applied for 90 days - bringing an elastic quality to the delivery mechanism and helping keep the balance of capacity vs budget with a flexible deployment to suit the revenue potential.

Sorted? Getting there but where does all the extra content and merchant service coming from? Temporary deployment of more servers is the usual method but this leads to other issues. Where are the servers coming from – buy them? Rent them? Licencing? Network considerations? Power? Christmas – Bah humbug!

Keeping an eye on the costs, it’s a given that most organisations wish to deploy the smallest possible of additional tin. Other posts in this blog go through server offload either as a solution concept or a basic technical overview but to summarise, utilising a NetScaler appliance will reduce the number of servers deployed to provide the content, particularly with the AppCache feature. Still need to add more servers but fewer of them…

So on site capacity works for some but what about those data centres that are already bursting at the seams?

Cloud platforms that offer IaaS are a genuine alternative – renting additional infrastructure from a trusted 3rd party is a very flexible way of keeping the cost/balance spot on which brings the next problem – how to manage the traffic between cloud provider and the on site resource? Easier said than done? In some cases yes but the post on Cloud Bridge could be well worth a read…

Right so the data centre  now has the content & capacity to deliver enough visitors to maximise revenue - how’s it all going? Analytic capabilities are next on the list as ‘you can’t manage what you can’t measure’….

Application Delivery Controllers (ADCs) are in the ideal position in the traffic stream to understand realtime performance – they see every part of the delivery from the server to the end point.  NetScaler App Flow (for use with 3rd party analysis tools) & Insight (currently in beta but due Q4) are invaluable in spotting everything from customer trends to poor performance and bringing this information to the hands of those that need it to make informed decisions. So that just leaves security…

If there are card transactions then PCI compliance is a must, everything else is reputation and/or revenue damaging and hackers are getting clever. Keep it safe and keep it stable often involves additional products all with their own implications on cost and complexity but again,  protection against malicious attack can be a function of the ADC – the AppFirewall post looks into typical existing production deployments and the level of security achieved while maintaining impressively simplified management overhead.

All of the above can be achieved by embarking on a mammoth mission with countless vendors to deploy various point products all of which need to be researched, trialed, procured, powered, cooled, managed and maintained. A big ask for a department that’s looking to do more with less.

If a single device can provide all of the above functionality, and more, then it needs to have the pedigree to give IT decision makers the confidence to trust it to keep their revenue streams open and the virtual checkouts ringing. NetScaler made a name for itself with the web monsters like Amazon & eBay and provides dynamic, scalable solutions which handle millions of transactions a day. The popular misconception is that NetScaler is only in the enterprise market and comes with a substantial price tag which is true if it’s delivering an enterprise level service. At the other end of the scale, virtual appliances are the perfect fit for those with more modest traffic levels, offering the same level of features with a price tag less than a top end MacBook. The smallest start-up company with big growth plans, or established brands with big customer bases and shareholders to please, Citrix have covered all bases.

Capacity costs money and keeping costs down is crucial in competitive markets, so it makes sense to look at ways of providing the right amount of infrastructure for the demand, no more, no less – e(lastic)Commerce could catch on - Al

© Al Taylor 28th Sept 2012

Scaling upMPX appliances has its limitations due to the actual hardware. Once an MPX7500 (1GB) has been upgraded to an MPX9500 (3GB) there’s no where else to go as 3Gb of throughput is the maximum capacity of the tin. Each of the physical appliances shared across the range has computational and resource limitations to enable the pricing to remain competitive. If an organisation needs more than 3GB in this example then the only option is a rip out and replace with a bigger appliance or the ‘forklift’ upgrade as it’s affectionately known.

Version 10 firmware which was released earlier in the year offers TriScale Clustering – the ability to cluster up to 32 NetScaler appliances together to work as one. In the smallest example, 2 VPX10 appliances could be clustered to offer a 20Mbps capacity or at the other end of the scale, 32 of the big MPX21550s could happily manage a combined total of a touch over one and half terabytes of throughput from a single management console. The use cases between the two examples are many and varied but there’s also the ever-present high availability (HA) pair ‘elephant in the room’ to consider.

After saving for months or committing to high monthly finance payments it’s hard to imagine a customer completing the paperwork at a BMW dealership and being presented with their shiny new pride and joy along with another identical one for when the first one breaks down but this is exactly what thousands of organisations have with their IT infrastructure and the HA pair. A production appliance to look after things and another one sitting there ready to take over but actually doing nothing. IT savvy Finance Directors hate HA pairs. The money has to be spent for infrequent benefit so applying a cluster licence to a HA pair in current production would allow greater capacity for peak/growth traffic but still maintain a service in times of an appliance going offline.

Feedback from the frontline however favors the ability to run a number of smaller appliances in a cluster with a single backup appliance (n+1 config). When traffic volumes are small, fewer appliances can be applied to the stack but when demand dictates, more appliances can be added on the fly to increase capacity and maintain SLAs.

Have a look at the TriScale Clustering post for more use cases- Al

© Al Taylor 26th Sept 2012

If you’re not familiar with the difference between MPX & SDX very simply MPX offers a single NetScaler in a physical appliance. SDX offers multiple NetScalers in a single physical appliance.

As organisations grow and look to support greater numbers of users, their infrastructure obviously needs to grow too. There’s a general rule of thumb that bigger environments with greater numbers of users have higher levels of service and as a result, sharing delivery mechanisms accross multiple appliacations is no longer an option. Enterprise organisations can’t afford to let end point performance drop on application A because application B is extremely busy and taking all the delivery resource. These larger use cases require individual app delivery controllers (ADCs) for each application silo to ensure the SLAs are maintained across the infrastructure. Multiple ADCs need more rack space, power, maintenance and management to look after so the NetScaler SDX is an alternative as it offers the SLA management of the stand alone method but with the various cost savings of deploying far fewer physical appliances in the data centre.

Each NetScaler SDX physical appliance ships with a licence key that allows 5 individual NetScaler images(refered to as instances) to be run on the hardware. Each of these instances can be configured as a stand alone appliance with further packs of 5 instances available to add by licence key should more applications require delivery managment. It’s possible to have up to 40 individual instances running on a single physical appliance which really starts to push the boundaries of application delivery controllers, as a result, Citrix refer to the SDX appliances as Service Delivery Controllers (SDCs)

Adding more insatances in a single physical appliance – Scale In – Al

© Al Taylor 26th Sept 2012

As the name suggests, TriScale offers three methods of scaleability for organisations that have deployed NetScaler in to their infrastructure. There are a couple of caveats based around the type and specification of the original appliance so add a comment or drop me a mail if you need to find out the options for a specific requirement….

Scale Up - Capacity increase by licence key – applies to VPX, MPX & SDX appliances.

NetScaler data sheets show a range of 39 hardware appliances available at the time of writing, namely the MPX & SDX platforms. There are however only a handful of physical boxes produced by the vendor, the rest of the product choice being dictated by the licence key applied to the hardware. As an example, the popular MPX7500 1GB appliance is the exact same piece of tin used by the MPX9500 3GB appliance only with a different licence key applied.

If an organisation starts out with an MPX 7500 appliance they can therefor apply an upgrade licence key to increase the capacity of the device to and turn it in to the MPX9500 with 3x system throughput, in other words, scale the appliance up. If the increase in capacity is required on a permanent basis, no problem but some organisations find they have to seasonal peaks in traffic which they have to provision for. Classic example would be an eCommerce site that has steady traffic volumes throughout the year but massive spikes around the Christmas & New Year sales.

Historically, these organisations need to over provision their infrastructure to cope with peak volumes of visits but Citrix have boxed this off quite nicely with their 90 Burst licence. Apply a 90 day burst licence to an MPX7500 and for a touch under three months you have an MPX 9500 with 3GB worth of capacity to keep those virtual checkouts ringing. Best bit though is that on day 91 the appliance reverts back to a 1GB capacity MPX7500 – why’s that the best bit? Because an organisation can keep the costs down in low season and make hay while the sunshines. Take it a step further with the Cloud Bridge feature opening a back door from the data centre in to AWS or similar for additional compute power and ker-ching! Massively under utilised in the UK from my past experience- Al

For more on NetScaler Triscale have a look at Up, In and Out….Scale In & Up In & Out…..Scale Out

© Al Taylor 26th Sept 2012

• AjF
• DJ $ Bill
• DJ Al-D
• DJ Chip
• DJ Rinzy
• DJ Sisler
• DJ the DJ
• Groova Scape
• Jerry Wimmer
• Karaoke
• Open Mic Night
• Triscale

For all of the information you need on these shows, check out Today’s Calendar on RoanokeNights.com. If you have any additions or updates, please leave a comment below. Enjoy your Thursday!

• Bebop Hoedown
• Corey Hunley
• DJ $ Bill
• DJ Chip
• DJ Rinzy
• DJ the DJ
• DJ Todd
• Karaoke
• Lazy Man Dub Band
• My Radio
• Pool Tournaments
• The Pop Rivets
• Triscale

Looks to be a good night, if you have any updates/additions please leave comments below. Enjoy your Saturday!

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