{"id":210,"date":"2013-06-17T12:37:08","date_gmt":"2013-06-17T10:37:08","guid":{"rendered":"http:\/\/e3mag.com\/?p=210"},"modified":"2019-04-01T10:57:52","modified_gmt":"2019-04-01T08:57:52","slug":"the-new-old-cluster","status":"publish","type":"post","link":"https:\/\/e3mag.com\/en\/das-neue-alte-cluster\/","title":{"rendered":"The new old cluster"},"content":{"rendered":"

We have been working for many years with the Protection<\/span> business-critical applications through clusters. Installation<\/span> and sale of complex Systems<\/span> is certainly the first stage of the life cycle.<\/p>\n

At this point, operation begins. A decisive parameter here is the Availability<\/span> the Application<\/span>.<\/p>

\"\"<\/a><\/div>\n

Well, we didn't discover that, but our colleagues already recognized it in the great age of the Unix<\/span>-operating systems.<\/p>\n

The legendary VMS Cluster, Veritas Cluster Server for Solaris or the True64 Cluster have set high standards in this area. Availability<\/span> set.<\/p>\n

LifeKeeper was also available as an in-house product for NCR's MP-RAS and was one of the first solutions to be ported to the x86 world.<\/p>\n

Microsoft Windows NT 3.5 became the preferred operating system basis - was that a coincidence?<\/p>\n

Troubleshooting<\/h3>\n

As is well known, the availability cluster consists of at least two Servers<\/span>to increase redundancy.<\/p>\n

With a well thought-out architecture, the resulting overall system should no longer contain a single point of failure (SPoF).<\/p>\n

The second and almost more important starting point for avoiding system failures is application monitoring.<\/p>\n

And this is where the products sometimes differ greatly.<\/p>\n

The more precise and flexible the monitoring of the Application<\/span> can be adapted to the respective application, the more Error<\/span> can be recognized.<\/p>\n

The<\/span> The best testing depth is usually achieved with solutions that Application<\/span> be supplied by the customer.<\/p>\n

However, if different cluster solutions are Application<\/span> the right way for data center operation and can all specific adjustments be made?<\/p>\n

There is no doubt that the overall failure of a cluster node brings clear conditions - but it is usually not so trivial. And without regular functionality checks, the expected result is not necessarily achievable in the event of an error.<\/p>\n

Besides Hardware<\/span> and the Application<\/span> of course, the Data<\/span> be protected.<\/p>\n

Virtualization as a solution<\/h3>\n

Since there are a number of points to consider when setting up and operating a cluster in order to achieve the desired goal, server virtualization with its possibilities seemed to be a welcome solution, which would also reduce theAvailability<\/span> the Systems<\/span> with increased.<\/p>\n

I would not dispute this, even though an additional virtualization layer has been introduced - in practice, however, this has proven to be stable.<\/p>\n

The<\/span> Possibility of virtualized Systems<\/span> simply moving from one hardware node to another is undoubtedly a wonderful thing.<\/p>\n

But how do I know when I need to do this, and will replacing the hardware solve the problem?<\/p>\n

The<\/span> Virtualization software detects both the failure of a Host<\/span>-system, but can also be the operating system of the guest system monitor<\/span>.<\/p>\n

The Application<\/span> remains outside<\/h3>\n

This is where our experience in application monitoring can be put to good use. It is certainly possible to implement a classic cluster as a virtualized system, provided certain conditions are met.<\/p>\n

However, the option of relying on experience with the Protection<\/span> of applications, and the switching of the Virtualization<\/span> to leave.<\/p>\n

In addition to the long-awaited simplifications, server virtualization has also (unintentionally) led to an enormous increase in the number of Systems<\/span> can lead to.<\/p>\n

Because the Application<\/span> cluster, increases the number of Systems<\/span> even further.<\/p>\n

The idea of the One Node Cluster was developed out of this need.<\/p>\n

Is it enough for many Error<\/span>the system or even just the Application<\/span> at monitor<\/span> and restart it if necessary?<\/p>\n

It certainly makes sense, but a nice name would have been part of it. One Node Cluster is like a single family - but we know in the IT<\/span> already know what we're talking about, at least most of the time.<\/p>\n

Maintaining an overview<\/h3>\n

To avoid introducing additional complexity and confusion into system administration, we pay attention to integrated Administration<\/span> application monitoring.<\/p>\n

It cannot be the goal of the Administration<\/span> the Virtualization<\/span> of the usually very many Systems<\/span> to think about which Systems<\/span> operated in the cluster or assigned to the various Host<\/span>-systems and so on.<\/p>\n

I already had this experience with one of our first cluster installations for the Protection<\/span> a Database<\/span> made.<\/p>\n

The Customer<\/span> wanted to use an offlineFuse<\/span> his Database<\/span> and held the Database<\/span> on the first node - offline still didn't work: right.<\/p>\n

Protection<\/h3>\n

With the ever-increasing dependence of almost all processes on the IT<\/span> the willingness to deal with the disaster is growing - slowly.<\/p>\n

The<\/span> not quite cheap perfection certainly consists in a Backup<\/span>-Data center<\/span> or computer room.<\/p>\n

Solutions are often offered that at least Data<\/span> replicate to a second location. Only: The<\/span> Data alone is just ones and zeros.<\/p>\n

The next step would therefore be to also have the applications ready in the event of a disaster.<\/p>\n

In addition to the possibilities offered by virtualization solutions, the cluster across data center boundaries - the so-called stretched cluster - is a good option.<\/p>\n

It also makes sense to configure applications on physical Servers<\/span> in the event of a fault with virtualized systems.<\/p>\n

With the right framework conditions, there is nothing to be said against the virtual Data center<\/span> in the Cloud, but native!<\/span>to protect against disaster.<\/p>\n

None of these solutions are as simple as the brochure suggests, as things usually turn out differently than expected. The technical basis is certainly the replication of the Data<\/span> into the Cloud, but native!<\/span>.<\/p>\n

After the Installation<\/span> the Application<\/span> is also the access of users to the Cloud, but native!<\/span>-Systems<\/span> the next challenge. A multiple Test<\/span> is an important success factor here.<\/p>\n

SAP<\/span>-Systems<\/span><\/h3>\n

We have not even considered the SAP<\/span>-Systems<\/span>. As highly business-critical Systems<\/span> they are naturally predestined for application protection.<\/p>\n

There is also enough SPoF on the individual system.<\/p>\n

As a commitment to application availability, the High AvailabilityCertification<\/span> which is supported by the LinuxLab of the SAP<\/span> was introduced last year.<\/p>\n

Up to this point, cluster solutions were classified as middleware and were not assigned to any Test<\/span> subjected to.<\/p>\n

But not only the technical test catalog is the subject of the SAP<\/span>-Certification<\/span> for cluster products.<\/p>\n

For us and our Customers<\/span> Particularly important was the Certification<\/span> In the event of a fault, the associated commitment to continue to operate in this environment without deactivating the cluster components Support<\/span> to perform.<\/p>\n

To this end, a defined support process, the definition of which is part of the Certification<\/span> is to integrate the providers of the availability solution into the support process.<\/p>\n

Another important component of cluster certification is the possibility of SAP<\/span>-clusters via SAP Adaptive Computing Controller (ACC) or Landscape Virtualization Management (LVM<\/span>) can be controlled.<\/p>\n

Together with our colleagues in St. Leon-Rot, we are currently investigating whether it makes sense and is practicable, SAP<\/span>-Systems<\/span> with a Cloud, but native!<\/span>-solution to protect against disaster.<\/p>\n

Conclusion<\/h3>\n

The emperor is dead - long live the emperor.<\/p>\n

No, I don't want to claim that clusters will continue to exist forever in the same way they were developed years ago.<\/p>\n

In addition to its importance for disaster protection, knowledge of application monitoring is increasingly becoming the focus for increasing the Availability<\/span>.<\/p>\n

However, it is also important that the availability solution can be integrated into management systems that Hardware<\/span> or virtualization environments monitor<\/span> and control. If you keep this in mind and try to master the complexity of the overall solution, clusters continue to be a good means of Fuse<\/span> the availability of applications.<\/p>\n

The modern emperor lives.<\/p>\n

 <\/p>","protected":false},"excerpt":{"rendered":"

Cluster - to some ears, the term sounds like a relic from years long gone. Why would we still need something like that in the age of cloud and virtualization?<\/p>","protected":false},"author":12,"featured_media":4163,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"pmpro_default_level":"","footnotes":""},"categories":[10,7,2538],"tags":[75,59],"coauthors":[24267],"class_list":["post-210","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-das-aktuelle-stichwort","category-meinung","category-mag1306","tag-cluster","tag-microsoft","pmpro-has-access"],"acf":[],"featured_image_urls_v2":{"full":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort.jpg",1000,431,false],"thumbnail":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort-150x150.jpg",150,150,true],"medium":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort.jpg",400,172,false],"medium_large":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort-768x331.jpg",768,331,true],"large":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort.jpg",1000,431,false],"image-100":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort-100x43.jpg",100,43,true],"image-480":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort-480x207.jpg",480,207,true],"image-640":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort-640x276.jpg",640,276,true],"image-720":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort-720x310.jpg",720,310,true],"image-960":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort-960x414.jpg",960,414,true],"image-1168":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort.jpg",1000,431,false],"image-1440":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort.jpg",1000,431,false],"image-1920":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort.jpg",1000,431,false],"1536x1536":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort.jpg",1000,431,false],"2048x2048":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort.jpg",1000,431,false],"trp-custom-language-flag":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort.jpg",18,8,false],"bricks_large_16x9":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort.jpg",1000,431,false],"bricks_large":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort.jpg",1000,431,false],"bricks_large_square":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort.jpg",1000,431,false],"bricks_medium":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort.jpg",600,259,false],"bricks_medium_square":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort.jpg",600,259,false],"profile_24":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort-24x24.jpg",24,24,true],"profile_48":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort-48x48.jpg",48,48,true],"profile_96":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort-96x96.jpg",96,96,true],"profile_150":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort-150x150.jpg",150,150,true],"profile_300":["https:\/\/e3mag.com\/wp-content\/uploads\/2016\/12\/Das-aktuelle-Stichwort-300x300.jpg",300,300,true]},"post_excerpt_stackable_v2":"

Cluster \u2013 der Begriff klingt in manchen Ohren wie ein Relikt aus l\u00e4ngst vergangenen Jahren. Wozu sollten wir in Zeiten von Cloud und Virtualisierung so etwas noch ben\u00f6tigen?<\/p>\n","category_list_v2":"Das aktuelle Stichwort<\/a>, Die Meinung der SAP-Community<\/a>, MAG 13-06<\/a>","author_info_v2":{"name":"Gerd Jelinek, CC","url":"https:\/\/e3mag.com\/en\/author\/gerd-jelinek\/"},"comments_num_v2":"0 comments","_links":{"self":[{"href":"https:\/\/e3mag.com\/en\/wp-json\/wp\/v2\/posts\/210","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/e3mag.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/e3mag.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/e3mag.com\/en\/wp-json\/wp\/v2\/users\/12"}],"replies":[{"embeddable":true,"href":"https:\/\/e3mag.com\/en\/wp-json\/wp\/v2\/comments?post=210"}],"version-history":[{"count":0,"href":"https:\/\/e3mag.com\/en\/wp-json\/wp\/v2\/posts\/210\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/e3mag.com\/en\/wp-json\/wp\/v2\/media\/4163"}],"wp:attachment":[{"href":"https:\/\/e3mag.com\/en\/wp-json\/wp\/v2\/media?parent=210"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/e3mag.com\/en\/wp-json\/wp\/v2\/categories?post=210"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/e3mag.com\/en\/wp-json\/wp\/v2\/tags?post=210"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/e3mag.com\/en\/wp-json\/wp\/v2\/coauthors?post=210"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}