分类目录归档:Cloud-Common

[repost ]5 Ways To Make Cloud Failure Not An Option

original:http://highscalability.com/blog/2012/12/5/5-ways-to-make-cloud-failure-not-an-option.html

With cloud SLAs generally being worth what you don’t pay for them, what can you do to protect yourself? Sean Hull in AirBNB didn’t have to fail  has some solid advice on how to deal with outages:

  1. Use Redundancy. Make database and webserver tiers redundant using multi-az or alternately read-replicas.
  2. Have a browsing only mode. Give users a read-only version of your site. Users may not even notice failures as they will only see problems when they need to perform a write operation.
  3. Web Applications need Feature Flags. Build in the ability to turn off and on major parts of your site and flip the switch when problems arise.
  4. Consider Netflix’s Simian. By randomly causing outages in your application you can continually test your failover and redundancy infrastructure.
  5. Use multiple clouds. Use Redundant Arrays of Inexpensive Clouds as a way of surviving outages in any one particular cloud.

None of these are easy and it’s worth considering that your application may not need them at all. Life will almost always go on anyway.

Sean has many more details in AirBNB didn’t have to fail.

[repost ]Are We Seeing The Renaissance Of Enterprises In The Cloud?

original:http://highscalability.com/blog/2012/11/5/are-we-seeing-the-renaissance-of-enterprises-in-the-cloud.html

A series of recent surveys on the subject seems to indicate that this is indeed the case:

Research conducted by HPclip_image001 found that the majority of businesses in the EMEA region are planning to move their mission-critical apps to the cloud. Of the 940 respondents, 80 percent revealed plans to move mission-critical apps at some point over the next two to five years.

A more recent survey, by research firm MeriTalkclip_image001[1] and sponsored by VMware and EMC (NYSE:EMCclip_image001[2]), showed that one-third of respondents say they plan to move some mission-critical applications to the cloud in the next year. Within two years, the IT managers said they will move 26 percent of their mission-critical apps to the cloud, and in five years, they expect 44 percent of their mission-critical apps to run in the cloud.

The Challenge – How to Bring Hundreds of Enterprise Apps to the Cloud

The reality is that cloud economics only start making sense when there are true workloads that utilize the cloud infrastructure.

If the large majority of your apps fall outside of this category, then you’re not going to benefit much from the cloud. In fact, you’re probably going to lose money, rather than save money.

The Current Approach

  • Focus on building IaaS - Current cloud strategies of many enterprises has been centered on making the infrastructure cloud ready. This basically means ensuring that they are able to spawn machines more easily than they were before. A quick look at many initiatives of this nature shows that there is still only a small portion of enterprises whose applications run on such new systems.
  • Build a new PaaS - PaaS has been taught as the answer to run apps on the cloud. The reality however, is that most of the existing PaaS solutions only cater to new apps and quite often the small, and “non” mission-critical share of our enterprise applications, which still leaves the majority of our enterprise workload outside of our cloud infrastructure.
  • App Migration as a One Off Project - The other approach for migrating applications to the cloud has been to select a small group of applications, and then migrate these one by one to the cloud. Quite often the thought behind this approach has been that application migration is a one-off project. The reality is that applications are more of a living organism – things fail, are moved, or need to be added and removed over time. Therefore it’s not enough to move apps to the cloud using some sort of virtualization technique, it’s critical that the way they’re run and maintained will also fit the dynamic nature of the cloud.

Why is This not Going to Work?

Simple math shows that if you apply this model to the rest of your apps, it’s probably going to take years of effort to migrate all your apps to the cloud. The cost of doing so is going to be extremely high, not to mention the time to market issue which can be even an even greater risk in the end, as it will reflect on cost of operation, profit margins and even the ability to survive in this an extremely competitive market, if it is too long.

What’s missing?

What we’re missing is a simple and systematic way to brings all these hundreds and thousands of apps to the cloud.

Moving Enterprise Workloads to the Cloud at a Massive Scale

Instead of thinking of cloud migration as a one-off thing, we need to think of cloud migration on a massive scale.

Thinking in such terms drives a fairly different approach.

In this post, I outlined what i believe should be the main principles for moving enterprise application at such a scale.

Read full post:http://www.cloudifysource.org/2012/10/30/moving_enterprise_workloads_to_the_cloud_on_a_massive_scale.html