{"id":3339,"date":"2011-10-28T12:55:19","date_gmt":"2011-10-28T17:55:19","guid":{"rendered":"http:\/\/jianmingli.com\/wp\/?p=3339"},"modified":"2012-07-09T20:24:30","modified_gmt":"2012-07-10T01:24:30","slug":"weblogic-11g-clustering-cluster-architectures","status":"publish","type":"post","link":"https:\/\/jianmingli.com\/wp\/?p=3339","title":{"rendered":"WebLogic 11g Clustering: Cluster Architectures"},"content":{"rendered":"
\n

Contents<\/h2>\n
    \n\t
  1. \n\t\tWeb Application Tiers<\/a>\n\t<\/li>\n\t
  2. \n\t\tRecommended Basic Architecture<\/a>\n\t<\/li>\n\t
  3. \n\t\tRecommended Multi-Tier Architecture<\/a>\n\t\t
      \n\t\t\t
    1. \n\t\t\t\tConfiguration considerations<\/a>\n\t\t\t<\/li>\n\t\t<\/ol>\n\t
    2. \n\t\tRecommended Proxy Architectures<\/a>\n\t<\/li>\n\t
    3. \n\t\tTwo-Tier Proxy Architecture<\/a>\n\t<\/li>\n\t
    4. \n\t\tMulti-Tier Proxy Architecture<\/a>\n\t<\/li>\n\t
    5. \n\t\tSecurity Options for Cluster Architectures<\/a>\n\t<\/li>\n\t
    6. \n\t\tReferences<\/a>\n\t<\/li>\n<\/ol>\n<\/ol>\n<\/div>\n
       <\/div>\n

      Web Application Tiers<\/h2><\/span>\n

      * Web tier: provides static web content, e.g. HTML pages.
      \n* Presentation tier: provides dynamic web content, e.g. Servlets and JSPs.
      \n* Object tier: provides Java objects, e.g. EJBs and RMI classes, and their associated business logic.<\/p>\n

      Recommended Basic Architecture<\/h2><\/span>\n

      * Combined tier architecture: all tiers of web application are deployed to the same WebLogic Server cluster.<\/p>\n

      \"\"<\/a><\/h6><\/span>\n

      * Pros:
      \n– Easy administration with a single cluster.
      \n– Flexible load balancing with load balancer in front of WebLogic server cluster.
      \n– Robust security with firewall in front of load balancer.
      \n– Optimal performance for applications where most presentation tier access object tier.
      \n* Cons:
      \n– Single point load balancing at web tier.<\/p>\n

      Recommended Multi-Tier Architecture<\/h2><\/span>\n

      * Uses two separate clusters:
      \n– One for static HTTP content and clustered servlets
      \n– One for clustered EJBs<\/p>\n

      \"\"<\/a><\/h6><\/span>\n

      * Pros:
      \n– EJB methods are load balanced.
      \n– More server load balancing options. For example, if most client accesses are HTTP and Servlets instead of EJB, you can use bigger machines for web\/presentation cluster. On the other hand, if most computing is done at EJB, then you can use bigger machines for object cluster.
      \n– Higher availability due to fewer single-points of failure.
      \n– More security options. For example, you can firewall the object layer to protect it more.<\/p>\n

      * Cons:
      \n– No collocation optimization for object calls.<\/p>\n

      Configuration considerations<\/h3><\/span>\n

      * More IP sockets usages:
      \n– one socket for replicating HTTP session sstates between primary and secondary servers.
      \n– one socket for each WebLogic server in EJB cluster, for accessing remote objects.
      \n* Hardware load balancers need to maintain sticky <\/em>connection to the client’s point-of-contact server in order to support in-memory session state replication.
      \n* Firewall Restrictions
      \n* Must bind all servers in the object cluster to public DNS names, rather than IP addresses.
      \n* If internal and external DNS names of ra WebLogic Server instance are not identical, set ExternalDNSName <\/em>to server’s external DNS name.<\/p>\n

      Recommended Proxy Architectures<\/h2><\/span>\n

      * Pros:
      \n– Utilizing existing web server hardware.
      \n– Familiar firewall policies.
      \n* Cons:
      \n– Additional administration (web server not in WebLogic domain structure. Need to install plug-ins).
      \n– Limited Load balancing options (unlike load balancer, round robin only).
      \n* Load balancer advantages:
      \n– No need to maintain proxy servers.
      \n– No need to install proxy plug-ins.
      \n– More load balancing strategies (proxy plug-ins support only round robin).<\/p>\n

      Two-Tier Proxy Architecture<\/h2><\/span>\n

      * Similar to recommended basic architecture except that static HTTP servers are hosted on a bank of web servers.
      \n* Web Layer cluster: servers only static HTTP content.
      \n– WebLogic Server with the HttpClusterServlet.
      \n– Apache with WebLogic Server apache Server (proxy) plug-in.
      \n– Netscape Enterprise Server with the WebLogic NSAPI proxy plug-in.
      \n– Microsoft IIS with WebLogic Server IIS proxy plug-in.<\/p>\n

      \"\"<\/a><\/h6><\/span>\n

      Multi-Tier Proxy Architecture<\/h2><\/span>\n

      * Similar to recommended multi-tier architecture except that static HTTP servers are hosted on a bank of web servers.<\/p>\n

      \"\"<\/a><\/h6><\/span>\n

      Security Options for Cluster Architectures<\/h2><\/span>\n

      * Place a firewall in front of load balancer or proxy server to provide first line of defense.
      \n* Optionally, place a second firewall in front of database to provide database security.<\/p>\n

      References<\/h2><\/span>\n

      * Cluster Architectures<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

      Web Application Tiers * Web tier: provides static web content, e.g. HTML pages. * Presentation tier: provides dynamic web content, e.g. Servlets and JSPs. * Object tier: provides Java objects, e.g. EJBs and RMI classes, and their associated business logic. … Continue reading →<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_exactmetrics_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[104],"tags":[588,558,157,590],"class_list":["post-3339","post","type-post","status-publish","format-standard","hentry","category-weblogic11g","tag-11g","tag-architecture","tag-cluster","tag-weblogic"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p8cRUO-RR","_links":{"self":[{"href":"https:\/\/jianmingli.com\/wp\/index.php?rest_route=\/wp\/v2\/posts\/3339","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/jianmingli.com\/wp\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/jianmingli.com\/wp\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/jianmingli.com\/wp\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/jianmingli.com\/wp\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3339"}],"version-history":[{"count":5,"href":"https:\/\/jianmingli.com\/wp\/index.php?rest_route=\/wp\/v2\/posts\/3339\/revisions"}],"predecessor-version":[{"id":5063,"href":"https:\/\/jianmingli.com\/wp\/index.php?rest_route=\/wp\/v2\/posts\/3339\/revisions\/5063"}],"wp:attachment":[{"href":"https:\/\/jianmingli.com\/wp\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3339"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/jianmingli.com\/wp\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3339"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/jianmingli.com\/wp\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3339"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}