MACROMEDIA COLDFUSION MX-CLUSTERCATS Use Manual Download

Page: 19 / 156

CHAPTER 2

Scalability and Availability Overview

This chapter describes the concepts involved in achieving scalable and highly available
web applications.

Contents

•

What is scalability? ................................................................................................ 10

•

Successful scalability implementations ................................................................... 13

•

What is website availability?................................................................................... 23

•

Creating scalable and highly available sites............................................................. 28

Summary of Contents for COLDFUSION MX-CLUSTERCATS

Page 1: ...macromedia Using ClusterCATS...

Page 2: ...ames of Macromedia Inc or other entities and may be registered in certain jurisdictions including internationally This product includes code licensed from RSA Data Security This guide contains links t...

Page 3: ...ty and Availability Overview 9 What is scalability 10 Performance 10 Load management 12 Successful scalability implementations 13 Designing and coding scalable applications 13 Avoiding common bottlene...

Page 4: ...ating clusters in UNIX 60 Removing clusters 62 Adding cluster members 63 Adding cluster members in Windows 63 Adding cluster members in UNIX 64 Removing cluster members 65 Removing cluster members in...

Page 5: ...110 Changing active passive settings 111 Changing active passive settings in Windows 111 Changing active passive settings in UNIX 112 Changing restricted unrestricted settings 113 Restricting unrestr...

Page 6: ...CATS dynamic IP addressing 133 Setting up maintenance IP addresses 133 Enabling ClusterCATS dynamic IP addressing 135 Using server failover 137 Static versus ClusterCATS dynamic IP addressing 137 Wind...

Page 7: ...bes how to use ClusterCATS the clustering technology that provides load balancing and failover services to assure high availability for your web servers Contents Developer resources viii About Macrome...

Page 8: ...macromedia com coldfusion Information on JRun Detailed product information on JRun and related topics http www macromedia com products jrun JRun Support Center Professional support programs that Macro...

Page 9: ...Portable Document Format PDF files The PDF files are included on the product CDs and are installed in the docs directory although they are an optional part of the installation JRun Developer Resource...

Page 10: ...626 0554 Web http www macromedia com Technical support Macromedia offers a range of telephone and web based support options Go to http www macromedia com support for a complete description of technic...

Page 11: ...ent of web server resources A cluster consists of two or more web servers located on a LAN or across a WAN Web servers included in a cluster operate as a single entity to provide rapid and reliable ac...

Page 12: ...cluster is a group of website resources including web servers files applications databases and even the network that act in unison providing reliable and rapid user access These resources can be clust...

Page 13: ...failover Provides seamless failover of a web server because of a hardware software or network connection to another member in the cluster ClusterCATS shields users from unplanned or planned server fa...

Page 14: ...ecific URL Distributed operations ClusterCATS uses a distributed operations model eliminating traffic bottlenecks and maximizing performance While other hardware and software load balancing solutions...

Page 15: ...rprise Server ColdFusion and JRun load manager Configurable load thresholds Real time load monitor Session state management server level HTTP server monitor and auto restart Real time web server avail...

Page 16: ...Explorer Windows only on page 48 and ClusterCATS Web Explorer UNIX only on page 49 The following table shows which components ClusterCATS installs on each platform You must run the installation progr...

Page 17: ...ions see Configuring DNS servers on page 34 Note ClusterCATS Server does not run on Windows 98 or Windows 95 Sun Solaris system requirements for ClusterCATS Server Sun SPARC workstation 100 MB of free...

Page 18: ...CATS Server Its system requirements are as follows Intel Pentium 200 Mhz or greater CPU 100 MB of free disk space 64 MB of RAM 128 MB recommended Windows NT Service Pack 5 or greater if running Window...

Page 19: ...chapter describes the concepts involved in achieving scalable and highly available web applications Contents What is scalability 10 Successful scalability implementations 13 What is website availabil...

Page 20: ...ce Following the construction and tuning efforts quality assurance testers should test and measure an application s performance prior to deployment to establish acceptable quality benchmarks If these...

Page 21: ...s to scale linearly relative to constraining resources For example when a processor is added to a single processor server the operating system incurs extra overhead in synchronizing threads and resour...

Page 22: ...round robin Internet DNS or third party clustering packages Hardware and software combinations Each option has distinct merits Most load balancing solutions today manage traffic based on IP packet flo...

Page 23: ...artitioning on page 15 Application session and state management As you create web applications you will probably create specific variables that you intend to carry across multiple interactions between...

Page 24: ...man Resources web application on a company intranet The HR Generalist adds two new employee records to the HR database by filling out a web form because two new employees have been hired The Generalis...

Page 25: ...s An example of a business service is an algorithm that automatically calculates shipping and handling charges for an order based on the total cost of the order In JRun this logic is contained within...

Page 26: ...perform poorly Instituting industry best practices such as coding standards design reviews and code walkthroughs can significantly help to alleviate this problem Processor capacity even a well archite...

Page 27: ...ces on a TCP IP network that allows network users to use hierarchical natural language names rather than computer IP addresses when searching for computer hosts servers on a network DNS is used extens...

Page 28: ...your web applications are to work well with DNS Zones and domains on page 18 DNS record types server aliases and round robin distribution on page 19 Zones and domains A Domain Name System is composed...

Page 29: ...address mapping where the natural language name is the primary name representing the IP address PTR Record contains the IP address to host name mapping This is the reverse lookup of the A record in wh...

Page 30: ...o perform load testing Load testing is important to your website s success because it lets you test its capacities before you deploy it so you can find and fix problems before they are exposed to your...

Page 31: ...s on the market including Segue s SilkPerformer Mercury Interactive s LoadRunner and RSW s e LOAD Each of these packages provides substantial Web enabled software testing solutions that help you effec...

Page 32: ...hy they occur The number of possibilities would be too large Minimize distributed environment load testing load testing in a distributed environment can be problematic if the network on which you perf...

Page 33: ...runtled customers who will look to your competitors for goods and services This section defines and describes website availability and failover Availability and reliability on page 23 Common failures...

Page 34: ...common than software failures hardware failures do occur and can include crashed hard drives blown processors and corrupted network cards Diagnosing and fixing these issues can be a lengthy endeavor...

Page 35: ...causing you to lose significant business Although the application provided many useful features and capabilities customers could not access them because the site s performance degraded to the point th...

Page 36: ...ons Unlike the primary backup scheme the multiple servers in a parallel scheme are considered peers and are grouped as a single entity to support one or more applications You can use identical cloned...

Page 37: ...gers real time Web based alerts and so on to the appropriate administrator for prompt attention Besides notifying the administrator that a problem has occurred you also want your failover solution to...

Page 38: ...for a website Clustering for scalability works by distributing load among servers in the cluster load balancing using an unintelligent but regular distribution sequence round robin DNS and routers or...

Page 39: ...nsidered semi intelligent devices because they can detect a server failure and redirect requests to other servers If a web server fails or stops responding the router stops sending packets to the unre...

Page 40: ...server in a cluster so it cannot effectively manage load to prevent failures Software based clustering solutions There are several kinds of software based clustering solutions on the market As with ha...

Page 41: ...servers in the cluster No single point of failure by distributing the load balancing and failover capabilities among multiple servers in a cluster or multiple clusters as opposed to relying on only a...

Page 42: ...r more comprehensive coverage Having the flexibility to integrate hardware with software means that your organization won t necessarily have to absorb a capital loss on a previous technology investmen...

Page 43: ...of your website Use the first section in this chapter to guide you through the decision making process When you have installed ClusterCATS read the last section in this chapter for important informat...

Page 44: ...forward lookup host name to address translation and reverse lookup address to host name translation be registered with your DNS server For evaluation purposes you can use host files but this is not re...

Page 45: ...DNS server s table However if a user enters a URL for a site that the browser on that computer has never visited the local DNS server must access the primary DNS server on the Internet to resolve the...

Page 46: ...requests a name translation Round robin DNS and ClusterCATS work well together You should not rely on just round robin DNS for distributing load for your business critical sites because DNS functiona...

Page 47: ...tes effectively with round robin DNS For example for a single location server cluster consisting of four servers you must configure round robin DNS across all four servers for the domain name and indi...

Page 48: ...m Windows If your IP address for the local system is the same as the IP of your web server setting up your site for ClusterCATS dynamic IP addressing can involve reinstalling your web server software...

Page 49: ...ation in a distributed setting and server to client communication Note You must open both ports on all affected firewalls These ports include the following Port 9123 for TCP and UDP access opening por...

Page 50: ...ication each web server in a cluster must participate as a member NT server in a domain Do not set a server in your cluster as the primary domain controller PDC ClusterCATS Server failover will interf...

Page 51: ...setup exe file from Windows Explorer or the Run dialog box 2 Accept the default installation directory or click Browse to select a different directory and click Next In this manual the installation d...

Page 52: ...The names types and install directories of the web servers you will be clustering The directory where JRun is installed Note The procedures in this section assume you have installed JRun ClusterCATS s...

Page 53: ...config file Enter Apache installation directory usr local apache Enter location of Apache config file httpd conf usr local apache conf Netscape You are prompted to enter the location of Netscape s ro...

Page 54: ...tscape only Enter all to provide failover support to all members of this server s cluster Enter subset to explicitly define the cluster members for which this server will provide failover support Ente...

Page 55: ...ent the server from reaching the peak threshold For more information see Server load thresholds on page 66 Email addresses for alarm recipients ClusterCATS generates alarm notifications for several ev...

Page 56: ...46 Chapter 3 Installing ClusterCATS...

Page 57: ...lusterCATS Administration 48 Creating clusters 54 Removing clusters 62 Adding cluster members 63 Removing cluster members 65 Server load thresholds 66 Session aware load balancing 72 Persistent sessio...

Page 58: ...r is the heart of the clustering and load balancing of ClusterCATS It must be installed on each server in your cluster The server monitors the status of all other web servers in a cluster and tracks a...

Page 59: ...uration clusters servers monitors and probes is represented by a unique icon You can manipulate the icons in much the same manner as you expand and collapse directory trees in the Windows Explorer For...

Page 60: ...a port other than 80 and password protect access to it Netscape considerations By default Netscape Enterprise Server assigns your web server a random six digit communication port number You can eithe...

Page 61: ...To open the Web Explorer 1 Open a web browser 2 Enter the following URL in the browser s address field For Netscape Enterprise Server v3 x http server name admin port admin serv btweb default html For...

Page 62: ...from each server in your cluster The Server Administrator lets you Change installation settings Add and remove the ClusterCATS filter from the web server service Stop and start the ClusterCATS service...

Page 63: ...ClusterCATS Web Explorer which lets you administer your entire cluster from one central computer you must use btadmin from each server in your cluster btadmin lets you Add and remove the ClusterCATS...

Page 64: ...p Wizard This section describes how to create clusters in both ways Creating clusters with the Cluster Setup Wizard on page 54 Manually creating clusters on page 59 Creating clusters with the Cluster...

Page 65: ...r dialog box appears 3 Enter a name for your cluster and click Next Make your cluster names logically consistent with their purpose For example Sales Web Customer Support Web and so on The List of Web...

Page 66: ...et the maintenance support option only when creating a cluster or adding a cluster member to a cluster You cannot configure or modify this option after you have created and added the cluster member to...

Page 67: ...Click Next The Alert Notification dialog box appears 13 Enter the name of your outbound SMTP mail server in the SMTP mail server field and the e mail address for a recipient of cluster alerts in the E...

Page 68: ...ts a site that must maintain persistent state on the same web server during a user session select Yes to enable session aware load balancing Otherwise select No and click Next The Load Balancing Devic...

Page 69: ...a new cluster using the fields as described in the following table Field Description Cluster Name Enter a unique name for the cluster Make cluster names logically consistent with their purpose For exa...

Page 70: ...onfigured with a maintenance IP address Using maintenance support requires that your cluster support ClusterCATS dynamic IP addressing For more information see ClusterCATS dynamic IP addressing Window...

Page 71: ...s logically consistent with their purpose for example Sales Web or Customer Support Web Web Server Name Enter the fully qualified host name for example doc macromedia com for the first server you want...

Page 72: ...uster icon and select Configure Administration The cluster s Properties dialog box opens displaying the Administration tab The server designated as the Admin Manager is the active entry in the drop do...

Page 73: ...me field enter the fully qualified host name of the web server for example doc macromedia com 4 If you use the ClusterCATS dynamic IP addressing scheme and the maintenance IP address is not bound to y...

Page 74: ...ers To add a cluster member to a cluster 1 Open the ClusterCATS Web Explorer if it is not already open 2 Click the Add Server link The Add Server page appears 3 Enter the fully qualified host name for...

Page 75: ...t click the server name and select Delete The selected cluster member is deleted from the cluster you selected Removing cluster members in UNIX Use the ClusterCATS Web Explorer to remove cluster membe...

Page 76: ...e Gradual redirection threshold the point at which HTTP requests begin to be redirected to other less loaded members in a cluster so the server s performance does not degrade or become unavailable By...

Page 77: ...e first Load Management field This is referred to as the peak load threshold In the example above the peak load threshold is set to 90 5 Enable the Gradual Redirection check box 6 Enter a new value in...

Page 78: ...ou selected The load monitor shows three lines Top line red Peak load threshold Middle line yellow Gradual Redirection load threshold Bottom line green JRun ColdFusion server load Adjusting load thres...

Page 79: ...adual Redirection check box 5 Drag the Gradual Redirection load threshold yellow to adjust it accordingly 6 Close the dialog box to apply the load threshold settings you configured Configuring load th...

Page 80: ...an Error Server cluster_member_name could not be found ensure that you used the correct fully qualified server name and that the server is running 4 Click the Server Attributes link The Connect To Ser...

Page 81: ...hange the peak load threshold enter a new numeric value less than 100 in the Standard Load Threshold field 9 Enable the Gradual Redirection check box if it is not already enabled 10 To change the Grad...

Page 82: ...oad balancing guarantees that users will not get bumped from the server on which they start their session until the session is complete regardless of the load thresholds that have been defined for tha...

Page 83: ...Member List page appears 4 Click the Administration link under Cluster Attributes The Cluster Administration page appears 5 Select the Enable session aware load balancing check box 6 Click OK to enabl...

Page 84: ...h the ClusterCATS session aware load balancing feature This ensures that multiple servers do not have concurrent access to the same session data For more information see Session aware load balancing o...

Page 85: ...all 7 Repeat this procedure for every server in the cluster Using shared files for session swapping To use file swapping the JRun server s local properties file should contain the following propertie...

Page 86: ...on persistence jdbc JDBCConnectionURL jdbc odbc JRunSessions session persistence jdbc JDBCSessionTable sessions session persistence jdbc JDBCSessionIDColumn id session persistence jdbc JDBCSessionData...

Page 87: ...ied string in the page accessed ClusterCATS restricts that server and redirects requests to other available servers in the cluster ClusterCATS continues to test the restricted server when the probe re...

Page 88: ...terCATS Explorer and select a server 2 Select Server New Monitor Alternatively you can right click the server and select New Monitor The New Monitor dialog box appears 3 Enter a name to assign to this...

Page 89: ...ctual URL of the site you want the probe to access and replace success string with a text string that appears on a page on the site you are probing Tips Be sure to include a space between the URL and...

Page 90: ...that restart web applications should be configured to run no more frequently than the time it takes to stop and restart ColdFusion This time is highly site specific because it depends on the system re...

Page 91: ...ring ColdFusion probes in UNIX This section describes the following Adding ColdFusion probes on page 81 Editing and removing ColdFusion probes on page 83 Adding ColdFusion probes To add a new ColdFusi...

Page 92: ...probe to automatically restart the ColdFusion Server upon detecting a failure However if you do not want ClusterCATS to automatically restart the ColdFusion Server upon detecting a failure replace RES...

Page 93: ...obe in the Web Server Name field 4 Click OK The Cluster Member List page appears 5 Click the Server Attributes link The Connect To Server page appears 6 Select the server that hosts the probe in the W...

Page 94: ...not return the user specified string in the page accessed ClusterCATS restricts that server and redirects requests to other available servers in the cluster ClusterCATS continues to test the restrict...

Page 95: ...r and select a server 2 Select Server New Monitor or right click the server and select New Monitor The New Monitor dialog box appears 3 Enter a name to assign to this probe s monitor in the Name field...

Page 96: ...OG URL enter the actual URL of the page you want the probe to test By default this is http your_server btauxdir jrunprobe jsp The probe opens the page and searches for the success_string success_strin...

Page 97: ...ct an actual failure on the JRun server Frequency sec Enter a time to indicate how often the probe checks the JRun server Probes that restart web applications should be configured to run no more frequ...

Page 98: ...e probe 6 Close all open dialog boxes An icon for the new probe appears under the Monitor Manager in the ClusterCATS Explorer Removing JRun probes To remove a JRun probe 1 Open the ClusterCATS Explore...

Page 99: ...er List page appears 4 Click the Server Attributes link The Connect To Server page appears 5 Select a server to add a probe to from the Web Server Name list box 6 Click OK The selected server s Proper...

Page 100: ...u want the probe to test By default this is http your_server btauxdir jrunprobe jsp The probe opens the page and searches for the success_string success_string enter a text string that appears at the...

Page 101: ...the JRun probe 10 To edit the probe click Edit A page with all the available probes appears 11 Edit the fields corresponding to the probe that you want to change and click Register Frequency sec Ente...

Page 102: ...or using the ClusterCATS Explorer on Windows only Note You must use Cisco LocalDirector Version 3 1 4 software or later Before configuring ClusterCATS with LocalDirector you must configure LocalDirect...

Page 103: ...installation and configuration Ensure that you have defined an IP address for LocalDirector and that the LocalDirector network interfaces are configured correctly You can use the ping utility to test...

Page 104: ...uster Properties or Configure Administration Both menu selections display the Cluster Properties dialog box as the following figure shows 8 Click the Load Balance tab and choose Cisco LocalDirector fr...

Page 105: ...server www yourcompany com you created in step 3 LocalDirector IP Address Enter the IP address of Cisco LocalDirector DFP Agent Listen Port Enter the port number on which the cluster s DFP agent shou...

Page 106: ...en the ClusterCATS Explorer and select a cluster 3 Select Configure Administration or right click the cluster and select Configure Configure The Cluster Properties dialog box displays 4 Click the Load...

Page 107: ...th ClusterCATS To integrate ClusterCATS with a third party load balancing device 1 In ClusterCATS Web Explorer click the Show Cluster link 2 Enter the fully qualified host name of a server to integrat...

Page 108: ...TS Explorer select a cluster 2 Select Configure Alarm Notification or right click the cluster and select Configure Alarm Notification The Alarm Notification dialog box displays 3 Select an event for w...

Page 109: ...ame field 3 Click OK The Cluster Member List page appears 4 Click the Alarm Notification link The Alarm Notification page appears 5 Enter the e mail address of the person you want to be notified about...

Page 110: ...to Macromedia s Technical Support team that contains basic configuration information about your cluster This information enables Macromedia to provide optimal support by understanding your environment...

Page 111: ...ield 3 Click OK The Cluster Member List page appears 4 Click the Support link The Cluster Support page appears Field Description SMTP gateway Enter the name of the server through which outgoing e mail...

Page 112: ...Enter the e mail address of a person in your organization to receive a copy of the nightly technical support e mail If more than one person should receive the e mail separate e mail addresses with com...

Page 113: ...ation Windows NT Only you may want to use this security setting if your organization is fairly large and contains many distributed administrator groups that need to access your server clusters To use...

Page 114: ...ver ClusterCATS Explorer will display user name and password prompts upon each attempt to access the servers from the ClusterCATS Explorer 2 In ClusterCATS Explorer select a cluster 3 Select Configure...

Page 115: ...ist in which NT domain by communicating with any Windows NT domain controller for the domain You can view the list of servers that exist in the Windows NT domain with the Network Neighborhood Windows...

Page 116: ...only if security is not a concern for example in a development or QA environment By default ClusterCATS administrator security is disabled However if you have previously configured the security mode f...

Page 117: ...nable local user authentication 6 Select Disabled to disable authentication 7 If using local user authentication enter a valid user name and password and click OK ClusterCATS requires you to enter a v...

Page 118: ...108 Chapter 4 Configuring Clusters...

Page 119: ...te some time However at some point you may need to update software and content or perform general maintenance tasks that are beyond the typical cluster creation and configuration activities Contents U...

Page 120: ...balancing and availability In passive state HTTP requests are passed directly to the web server without ClusterCATS Server interception For more information see Changing active passive settings on pag...

Page 121: ...t to a server that is in the passive state are passed directly to the web server without ClusterCATS Server processing Changing active passive settings in Windows To change a cluster member s state 1...

Page 122: ...Attributes link under Other The Connect To Server page appears 5 Select a server to connect to from the Web Server Name drop down box 6 Click OK The selected server s Properties page appears 7 Click t...

Page 123: ...113 Restricting unrestricting servers in UNIX on page 114 Restricting unrestricting servers in Windows To change restriction settings for a cluster member 1 Open the ClusterCATS Explorer and select a...

Page 124: ...ink under Other The Connect To Server page appears 5 Select a server to connect to from the Web Server Name drop down box 6 Click OK The selected server s Properties page appears 7 Click the Administr...

Page 125: ...ce mode the servers that temporarily assumed the restricted server s IP address and HTTP traffic return the IP address to the affected server so it can receive and process HTTP requests Note Macromedi...

Page 126: ...erties dialog box appears for the selected cluster member with the Load tab active 3 Change the peak load threshold to 0 so any additional HTTP requests will be redirected to other servers in the clus...

Page 127: ...ce mode 1 Physically go to the server and open the ClusterCATS Server Administrator by selecting Start Programs Macromedia ClusterCATS Server Administrator The ClusterCATS Server Administrator appears...

Page 128: ...e server in maintenance mode using the instructions in Using maintenance mode Windows only on page 115 2 Make your updates to the inactive server 3 Open a web browser on the cluster member and enter t...

Page 129: ...9 Click OK 10 In ClusterCATS Explorer right click a cluster member and select Monitor Load The Server Load monitor appears 11 Observe your cluster member at low usage levels until you are satisfied th...

Page 130: ...r the following reasons Using ClusterCATS Explorer to delete cluster members from a cluster does not delete the server s ClusterCATS configuration which is stored in the server s registry Running the...

Page 131: ...command line utilities for configuring administering and troubleshooting ClusterCATS clusters This chapter describes these utilities Contents Using btadmin 122 Using bt start server and bt stop serve...

Page 132: ..._install_directory directory If you run btadmin on Red Hat Linux the ksh shell must be installed The syntax for btadmin is btadmin start stop restart daemon btadmin enable disable add delete config op...

Page 133: ...r For Apache web servers enter https hostname Daemon Description appmgr Application manager daemon dfp Cisco LocalDirector s Dynamic Feedback Protocol daemon failover Failover daemon ipaliasd ClusterC...

Page 134: ...eset Use the reset option to reinitialize cluster configuration settings on the current server For more information see Resetting cluster members on page 120 help Use the help option to get a list of...

Page 135: ...rver that is bound to the ClusterCATS Server This command starts or stops either the Netscape Enterprise Server or Apache Web Server bt start server and bt stop server are invoked from the command lin...

Page 136: ...hows how btcfgchk displays configuration information for a system with one network adapter and two IP addresses btcfgchk FQHN is hartford brighttiger com El90x1 PRIMARY hartford brighttiger com 192 16...

Page 137: ...ress Use the ifconfig a command to see information about your adapter Name lookup for hostname failed btcfgchk was not able to determine the IP address for the specified host Your DNS server may be do...

Page 138: ...the system s main fully qualified host name The problem is either The host name maps to the wrong IP address The IP address that the host name maps to does not have an entry in the DNS table for the r...

Page 139: ...Sample output The following sample output from the hostinfo utility provides information about a set of round robin DNS host names hostinfo macromedia com Information for host macromedia com FQHN macr...

Page 140: ...ss BTBcastAddress BTMcastAddress BTLocalAddress BTSendSize BTRecvSize BTConsole BTLogFile BTSystem Press keys at run time d dump sniff configuration information H display this and more help h display...

Page 141: ...vides enhanced capabilities that let you customize your ClusterCATS implementation This chapter describes some of these options Contents ClusterCATS dynamic IP addressing Windows only 132 Using server...

Page 142: ...your network interface card NIC You must also ensure that the websites static IP addresses that reside on the web server on this computer are removed from the IP stack also with the Network icon in th...

Page 143: ...resses Setting up a maintenance IP address ensures that you have one static IP address on the system that is not assigned to a web server virtual server or website This address often referred to as th...

Page 144: ...ed Do not change the Domain field on this tab Note The computer name on the Identification tab should only be a NetBIOS name not a fully qualified host name FQHN For example support1 macromedia com is...

Page 145: ...addressing 1 Verify that you can access your server by its maintenance address If not assign one to the server using the procedure described in Setting up maintenance IP addresses on page 133 2 Config...

Page 146: ...IP Protocol and click Properties Click Advanced 7 Unbind the IP addresses from the web server s NIC by selecting each IP address in the IP Addresses region and clicking Remove This step removes the I...

Page 147: ...t when a server fails its IP address es can be assigned to other servers When the failed over server comes back online ClusterCATS returns the IP addresses to it without conflict On Windows clusters y...

Page 148: ...e upper threshold of performance at which a server is declared busy for load balancing purposes When a server reaches this critical threshold ClusterCATS redirects further service requests away from t...

Page 149: ...nerates three significant output variables that are sent in response to the probe agent s HTTP query CCLOADVALUE the load calculated by getsimpleload jsp getsimpleload cfm using one of the available l...

Page 150: ...it processes getsimpleload jsp you may have installed ClusterCATS before installing JRun In this case verify that the following is true JRunMetricThread class file is located in jrun lib ext The virt...

Page 151: ...g on UNIX 106 configuring on Windows 103 disabling 106 domain 105 local user 103 NT Domain 105 availability and reliability common failures 24 defined 23 elements of 23 failover considerations 25 samp...

Page 152: ...m port on web server 50 common failures 24 concurrency 14 creating clusters 54 in UNIX 60 in Windows 54 manually 59 Windows 54 with hardware solutions 29 with software solutions 30 D databases concurr...

Page 153: ...cs 138 session aware 72 session aware on UNIX 72 session aware on Windows 72 software based 30 third party devices in UNIX 97 third party devices in Windows 96 using a hardware solution 29 using round...

Page 154: ...IX 114 Windows 113 ROUND_TRIP_TIME 139 round robin DNS 30 configuration 37 LocalDirector 92 reverse entries 37 tables example 37 using with ClusterCATS 37 round trip request time 138 routers 92 Cisco...

Page 155: ...ancing metrics 140 sniff 130 troubleshooting DNS btcfgchk 126 hostinfo 129 U unrestricted mode 110 updating cluster members 118 upgrading servers 115 V virtual servers hardware based clustering 29 W W...

Page 156: ...146 Index...

Search results

Summary of Contents for COLDFUSION MX-CLUSTERCATS

Reviews:

Related manuals for COLDFUSION MX-CLUSTERCATS

Brands by name

Popular brands

MACROMEDIA COLDFUSION MX-CLUSTERCATS, Use Manual

Search results

Summary of Contents for COLDFUSION MX-CLUSTERCATS

Reviews:

Related manuals for COLDFUSION MX-CLUSTERCATS

Brands by name

Popular brands