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class="vector-toc-numb">5</span> <span>Further reading</span> </div> </a> <ul id="toc-Further_reading-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" title="Table of Contents" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Toggle the table of contents" > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span 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class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><style data-mw-deduplicate="TemplateStyles:r1251242444">.mw-parser-output .ambox{border:1px solid #a2a9b1;border-left:10px solid #36c;background-color:#fbfbfb;box-sizing:border-box}.mw-parser-output .ambox+link+.ambox,.mw-parser-output .ambox+link+style+.ambox,.mw-parser-output .ambox+link+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+style+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+link+.ambox{margin-top:-1px}html body.mediawiki .mw-parser-output .ambox.mbox-small-left{margin:4px 1em 4px 0;overflow:hidden;width:238px;border-collapse:collapse;font-size:88%;line-height:1.25em}.mw-parser-output .ambox-speedy{border-left:10px solid #b32424;background-color:#fee7e6}.mw-parser-output .ambox-delete{border-left:10px solid #b32424}.mw-parser-output .ambox-content{border-left:10px solid #f28500}.mw-parser-output .ambox-style{border-left:10px solid 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src="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/50px-Question_book-new.svg.png" decoding="async" width="50" height="39" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/75px-Question_book-new.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/100px-Question_book-new.svg.png 2x" data-file-width="512" data-file-height="399" /></a></span></div></td><td class="mbox-text"><div class="mbox-text-span">This article <b>needs additional citations for <a href="/wiki/Wikipedia:Verifiability" title="Wikipedia:Verifiability">verification</a></b>.<span class="hide-when-compact"> Please help <a href="/wiki/Special:EditPage/VMScluster" title="Special:EditPage/VMScluster">improve this article</a> by <a href="/wiki/Help:Referencing_for_beginners" title="Help:Referencing for beginners">adding citations to reliable sources</a>. Unsourced material may be challenged and removed.<br /><small><span class="plainlinks"><i>Find sources:</i> <a rel="nofollow" class="external text" href="https://www.google.com/search?as_eq=wikipedia&q=%22VMScluster%22">"VMScluster"</a> – <a rel="nofollow" class="external text" href="https://www.google.com/search?tbm=nws&q=%22VMScluster%22+-wikipedia&tbs=ar:1">news</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?&q=%22VMScluster%22&tbs=bkt:s&tbm=bks">newspapers</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?tbs=bks:1&q=%22VMScluster%22+-wikipedia">books</a> <b>·</b> <a rel="nofollow" class="external text" href="https://scholar.google.com/scholar?q=%22VMScluster%22">scholar</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.jstor.org/action/doBasicSearch?Query=%22VMScluster%22&acc=on&wc=on">JSTOR</a></span></small></span> <span class="date-container"><i>(<span class="date">July 2016</span>)</i></span><span class="hide-when-compact"><i> (<small><a href="/wiki/Help:Maintenance_template_removal" title="Help:Maintenance template removal">Learn how and when to remove this message</a></small>)</i></span></div></td></tr></tbody></table> <p>A <b>VMScluster</b>, originally known as a <b>VAXcluster</b>, is a <a href="/wiki/Computer_cluster" title="Computer cluster">computer cluster</a> involving a group of computers running the <a href="/wiki/OpenVMS" title="OpenVMS">OpenVMS</a> operating system. Whereas <a href="/wiki/Multiprocessing#Processor_coupling" title="Multiprocessing">tightly coupled multiprocessor</a> systems run a single copy of the <a href="/wiki/Operating_system" title="Operating system">operating system</a>, a VMScluster is <a href="/wiki/Multiprocessing#Processor_coupling" title="Multiprocessing">loosely coupled</a>: each machine runs its own copy of OpenVMS, but the disk storage, <a href="/wiki/Distributed_lock_manager" title="Distributed lock manager">lock manager</a>, and security domain are all cluster-wide, providing a <a href="/wiki/Single_system_image" title="Single system image">single system image</a> abstraction. Machines can join or leave a VMScluster without affecting the rest of the cluster. For enhanced availability, VMSclusters support the use of dual-ported disks connected to two machines or storage controllers simultaneously. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Initial_release">Initial release</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=VMScluster&action=edit&section=1" title="Edit section: Initial release"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p><a href="/wiki/Digital_Equipment_Corporation" title="Digital Equipment Corporation">Digital Equipment Corporation</a> (DEC) first announced VAXclusters in May 1983. At that stage, clustering required specialised communications hardware, as well as some major changes to low-level subsystems in the VMS operating system. The software and hardware were designed jointly. VAXcluster support was first added in VAX/VMS V4.0, which was released in 1984. This version only supported clustering over DEC's proprietary <i>Computer Interconnect</i> (CI). </p><p>At the center of each cluster was a <a href="/wiki/Star_coupler" title="Star coupler">star coupler</a>, to which every <i>node</i> (computer) and <a href="/wiki/Magnetic_disk" class="mw-redirect" title="Magnetic disk">data storage device</a> in the cluster was connected by one or two pairs of <i>CI cables</i>. Each pair of cables had a transmission rate of 70 megabits per second, a high speed for that era. Using two pairs gave an aggregate transmission rate of 140 megabits per second, with redundancy in case one cable failed; the star couplers also had redundant wiring for better availability. </p><p>Each CI cable connected to its computer via a <i>CI Port</i>, which could send and receive <a href="/wiki/Packet_(information_technology)" class="mw-redirect" title="Packet (information technology)">packets</a> without any CPU involvement. To send a packet, a CPU had only to create a small data structure in memory and append it to a "send" queue; similarly, the CI Port would append each incoming message to a "receive" queue. Tests showed that a VAX-11/780 could send and receive 3000 messages per second, even though it was nominally a 1-<a href="/wiki/Million_instructions_per_second" class="mw-redirect" title="Million instructions per second">MIPS</a> machine. The closely related <a href="/wiki/Mass_Storage_Control_Protocol" title="Mass Storage Control Protocol">Mass Storage Control Protocol</a> (MSCP) allowed similarly high performance from the mass storage subsystem. In addition, MSCP packets were easily transported over the CI allowing remote access to storage devices. </p><p>VAXclustering was an early clustering system to achieve commercial success (along with AT&T, <a href="/wiki/Tandem_Computers" title="Tandem Computers">Tandem Computers</a>,<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> and <a href="/wiki/Stratus_Computer" class="mw-redirect" title="Stratus Computer">Stratus Computers</a><sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup>), and was a major selling point for VAX systems. </p> <div class="mw-heading mw-heading2"><h2 id="Later_developments">Later developments</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=VMScluster&action=edit&section=2" title="Edit section: Later developments"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In 1986, DEC added VAXclustering support to their <a href="/wiki/MicroVAX" title="MicroVAX">MicroVAX</a> minicomputers, running over <a href="/wiki/Ethernet" title="Ethernet">Ethernet</a> instead of special-purpose hardware. While not giving the <a href="/wiki/High-availability_cluster" title="High-availability cluster">high-availability</a> advantages of the CI hardware, these <i>Local Area VAXclusters</i> (LAVc) provided an attractive expansion path for buyers of low-end minicomputers. LAVc also allowed <a href="/wiki/Diskless_node" title="Diskless node">diskless <i>satellite nodes</i></a> to bootstrap over the network using the system disk of a <i>bootnode</i>. </p><p>Later versions of OpenVMS (V5.0 and later) supported "mixed interconnect" VAXclusters (using both CI and Ethernet), and VAXclustering over DSSI (<a href="/wiki/Digital_Storage_Systems_Interconnect" title="Digital Storage Systems Interconnect">Digital Systems and Storage Interconnect</a>), <a href="/wiki/SCSI" title="SCSI">SCSI</a> and <a href="/wiki/FDDI" class="mw-redirect" title="FDDI">FDDI</a>, among other transports. Eventually, as high-bandwidth wide area networking became available, clustering was extended to allow satellite data links and long-distance terrestrial links. This allowed the creation of <i>disaster-tolerant clusters</i>; by locating the single VAXcluster in several diverse geographical areas, the cluster could survive infrastructure failures and natural disasters. </p><p>VAXclustering was greatly aided by the introduction of <a href="/wiki/Terminal_server" title="Terminal server">terminal servers</a> using the <a href="/wiki/Local_Area_Transport" title="Local Area Transport">LAT</a> protocol. By allowing ordinary serial terminals to access the host nodes via Ethernet, it became possible for any terminal to rapidly and easily connect to any host node. This made it much simpler to accomplish <a href="/wiki/Fail_over" class="mw-redirect" title="Fail over">fail over</a> of the user terminals from one node of the cluster to another. </p><p>Support for clustering over TCP/IP was added in OpenVMS version 8.4, which was released in 2010. With <a href="/wiki/Gigabit_Ethernet" title="Gigabit Ethernet">Gigabit Ethernet</a> now common and <a href="/wiki/10_Gigabit_Ethernet" title="10 Gigabit Ethernet">10 Gigabit Ethernet</a> being introduced, standard networking cables and cards are quite sufficient to support VMSclustering. </p> <div class="mw-heading mw-heading2"><h2 id="Features">Features</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=VMScluster&action=edit&section=3" title="Edit section: Features"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>OpenVMS supports up to 96 nodes in a single cluster, and allows mixed-architecture clusters, where VAX and Alpha systems, or Alpha and Itanium systems can co-exist in a single cluster (Various organizations have demonstrated triple-architecture clusters and cluster configurations with up to 150 nodes, but these configurations are not officially supported). </p><p>Unlike many other clustering solutions, VMScluster offers transparent and fully distributed read-write with record-level locking, which means that the same disk and even the same file can be accessed by several cluster nodes at once; the locking occurs only at the level of a single record of a file, which would usually be one line of text or a single record in a database. This allows the construction of high-availability multiply redundant database servers. </p><p>Cluster connections can span upwards of 500 miles (800 km), allowing member nodes to be located in different buildings on an office campus, or in different cities. </p><p>Host-based volume shadowing allows volumes (of the same or of different sizes) to be shadowed (mirrored) across multiple controllers and multiple hosts, allowing the construction of disaster-tolerant environments. </p><p>Full access into the <a href="/wiki/Distributed_lock_manager" title="Distributed lock manager">distributed lock manager</a> (DLM) is available to application programmers, and this allows applications to coordinate arbitrary resources and activities across all cluster nodes. This includes file-level coordination, but the resources and activities and operations that can be coordinated with the DLM are completely arbitrary. </p><p>With the supported capability of rolling upgrades and multiple system disks, cluster configurations can be maintained on-line and upgraded incrementally. This allows cluster configurations to continue to provide application and data access while a subset of the member nodes are upgraded to newer software versions.<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-cluster-docs_5-0" class="reference"><a href="#cite_note-cluster-docs-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> Cluster uptimes are frequently measured in years with the current longest uptime being at least sixteen years.<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=VMScluster&action=edit&section=4" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text">"Tandem History: An Introduction". <i>Center</i> magazine, vol 6 number 1, Winter 1986, a magazine for Tandem employees.</span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.fundinguniverse.com/company-histories/tandem-computers-inc-history/">"History of TANDEM COMPUTERS, INC. – FundingUniverse"</a>. <i>www.fundinguniverse.com</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2024-10-12</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.fundinguniverse.com&rft.atitle=History+of+TANDEM+COMPUTERS%2C+INC.+%E2%80%93+FundingUniverse&rft_id=https%3A%2F%2Fwww.fundinguniverse.com%2Fcompany-histories%2Ftandem-computers-inc-history%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AVMScluster" class="Z3988"></span></span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFCovi1992" class="citation journal cs1">Covi, K. R. (July 1992). <a rel="nofollow" class="external text" href="https://dx.doi.org/10.1147/rd.364.0781">"Three-loop feedback control of fault-tolerant power supplies in IBM Enterprise System/9000 processors"</a>. <i>IBM Journal of Research and Development</i>. <b>36</b> (4): <span class="nowrap">781–</span>789. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1147%2Frd.364.0781">10.1147/rd.364.0781</a>. <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/0018-8646">0018-8646</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=IBM+Journal+of+Research+and+Development&rft.atitle=Three-loop+feedback+control+of+fault-tolerant+power+supplies+in+IBM+Enterprise+System%2F9000+processors&rft.volume=36&rft.issue=4&rft.pages=%3Cspan+class%3D%22nowrap%22%3E781-%3C%2Fspan%3E789&rft.date=1992-07&rft_id=info%3Adoi%2F10.1147%2Frd.364.0781&rft.issn=0018-8646&rft.aulast=Covi&rft.aufirst=K.+R.&rft_id=http%3A%2F%2Fdx.doi.org%2F10.1147%2Frd.364.0781&rfr_id=info%3Asid%2Fen.wikipedia.org%3AVMScluster" class="Z3988"></span></span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://vmssoftware.com/docs/VSI_OpenVMS_Cluster_Systems.pdf">"VSI OpenVMS Cluster Systems"</a> <span class="cs1-format">(PDF)</span>. August 2019.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=VSI+OpenVMS+Cluster+Systems&rft.date=2019-08&rft_id=https%3A%2F%2Fvmssoftware.com%2Fdocs%2FVSI_OpenVMS_Cluster_Systems.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AVMScluster" class="Z3988"></span></span> </li> <li id="cite_note-cluster-docs-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-cluster-docs_5-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://vmssoftware.com/products/clusters/">"VSI Products – Clusters"</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=VSI+Products+%E2%80%93+Clusters&rft_id=https%3A%2F%2Fvmssoftware.com%2Fproducts%2Fclusters%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AVMScluster" class="Z3988"></span></span> </li> <li id="cite_note-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-6">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20120203204940/http://uptimes-project.org/hosts/os_breakdown_list/OpenVMSClust">Uptimes Project breakdown for VMSclusters</a>.</span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="Further_reading">Further reading</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=VMScluster&action=edit&section=5" title="Edit section: Further reading"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li>Nancy P. Kronenberg, Henry M. Levy, William D. Strecker, <a rel="nofollow" class="external text" href="http://portal.acm.org/citation.cfm?id=214419.214421">"VAXcluster: a closely-coupled distributed system"</a>. <i>ACM Transactions on Computer Systems</i> <b>4</b> (2), 1986</li> <li><a rel="nofollow" class="external text" href="http://www.hpl.hp.com/hpjournal/dtj/vol3num3/toc.htm"><i>DIGITAL Technical Journal,</i> <b>3</b> (3), 1991</a> This issue was devoted to VAXclusters and FDDI networking. (Archived as PDF files.)</li></ul>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?useformat=desktop&type=1x1&usesul3=0" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" href="https://en.wikipedia.org/w/index.php?title=VMScluster&oldid=1276625514">https://en.wikipedia.org/w/index.php?title=VMScluster&oldid=1276625514</a>"</div></div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" class="mw-normal-catlinks"><a href="/wiki/Help:Category" title="Help:Category">Categories</a>: <ul><li><a href="/wiki/Category:Cluster_computing" title="Category:Cluster computing">Cluster computing</a></li><li><a href="/wiki/Category:OpenVMS" title="Category:OpenVMS">OpenVMS</a></li><li><a href="/wiki/Category:Hewlett-Packard" title="Category:Hewlett-Packard">Hewlett-Packard</a></li></ul></div><div id="mw-hidden-catlinks" class="mw-hidden-catlinks mw-hidden-cats-hidden">Hidden categories: <ul><li><a href="/wiki/Category:Articles_needing_additional_references_from_July_2016" title="Category:Articles needing additional references from July 2016">Articles needing additional references from July 2016</a></li><li><a href="/wiki/Category:All_articles_needing_additional_references" title="Category:All articles needing additional references">All articles needing additional references</a></li></ul></div></div> </div> </main> </div> <div class="mw-footer-container"> <footer id="footer" class="mw-footer" > <ul id="footer-info"> <li id="footer-info-lastmod"> This page was last edited on 19 February 2025, at 22:38<span class="anonymous-show"> (UTC)</span>.</li> <li id="footer-info-copyright">Text is available under the <a href="/wiki/Wikipedia:Text_of_the_Creative_Commons_Attribution-ShareAlike_4.0_International_License" title="Wikipedia:Text of the Creative Commons Attribution-ShareAlike 4.0 International License">Creative Commons Attribution-ShareAlike 4.0 License</a>; additional terms may apply. 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