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Strany 1 - Using ClusterCATS

macromedia® Using ClusterCATS

Strany 2

x About This BookContacting MacromediaCorporate headquartersMacromedia, Inc.600 Townsend StreetSan Francisco, CA 94103Tel: 415.252.2000Fax: 415.62

Strany 3 - CONTENTS

90 Chapter 4 Configuring Clusters9 Configure the application probe settings as described in the following table: Field DescriptionStatus This is an

Strany 4

Using JRun probes 9110 Click Register to create the probe. ClusterCATS begins to test the selected server immediately.Editing and removing JRun probes

Strany 5 - C o n t e n t s v

92 Chapter 4 Configuring ClustersLoad-balancing devicesYou can configure ClusterCATS to work in conjunction with a third-party hardware load-balanc

Strany 6

Load-balancing devices 93LocalDirector dynamic-feedback command settingsUse the LocalDirector dynamic-feedback command options as described in this se

Strany 7 - ABOUT THIS BOOK

94 Chapter 4 Configuring Clusters7 Select Cluster > Properties or Configure > Administration. Both menu selections display the Cluster Proper

Strany 8 - Developer resources

Load-balancing devices 959 Edit the cluster properties as described in the following table: 10 Click OK.When configured, ClusterCATS automatically set

Strany 9 - Viewing online documentation

96 Chapter 4 Configuring ClustersUsing third-party load-balancing devices in WindowsTo integrate ClusterCATS with a third-party load-balancing devi

Strany 10 - Contacting Macromedia

Load-balancing devices 97Using third-party load-balancing devices in UNIXYou cannot take advantage of ClusterCATS support of Cisco LocalDirector with

Strany 11 - Before You Begin

98 Chapter 4 Configuring ClustersAdministrator alarm notificationsThe ClusterCATS alarm notification feature provides instant feedback about critic

Strany 12 - ClusterCATS overview

Administrator alarm notifications 99Configuring administrator alarm notifications on UNIXTo configure administrator alarm notifications:1 In ClusterCA

Strany 13 - Detailed overview

1CHAPTER 1Before You BeginClusterCATS is a web server clustering technology that provides load-balancing and failover services that assure high availa

Strany 14 - • A user employs a bookmark

100 Chapter 4 Configuring ClustersAdministrator e-mail options The ClusterCATS administration e-mail support feature reports vital statistics about

Strany 15 - ClusterCATS overview 5

Administrator e-mail options 1013 Edit the e-mail support options as described in the following table: 4 Click OK to enable the ClusterCATS Report and

Strany 16 - ClusterCATS components

102 Chapter 4 Configuring Clusters5 Edit the e-mail support fields as described in the following table: 6 Click OK to enable the ClusterCATS Report

Strany 17 - System requirements

Administering security 103Administering securityWhen you enable ClusterCATS administration security for a cluster, only authorized users are able to a

Strany 18

104 Chapter 4 Configuring ClustersTo configure authentication modes for your clusters:1 Create a user account on each server within your cluster fo

Strany 19 - CHAPTER 2

Administering security 105Configuring Windows NT domain authenticationWindows NT Domain authentication lets ClusterCATS authenticate administrators wh

Strany 20 - What is scalability?

106 Chapter 4 Configuring Clusters10 Select NT Domain from the Mode drop-down box.11 Enter a valid user name and password that participates in the

Strany 21 - What is scalability? 11

Administering security 107The Cluster Authentication page appears:5 Select Local User from the Authentication drop-down box to enable local-user authe

Strany 22 - Load management

108 Chapter 4 Configuring Clusters

Strany 23

109CHAPTER 5Maintaining Cluster MembersAfter you have created your clusters, added servers to them, and configured them with load-balancing and high-a

Strany 24

2 Chapter 1 Before You BeginClusterCATS overviewThe ClusterCATS technology provides robust features for website availability, load balancing, and f

Strany 25

110 Chapter 5 Maintaining Cluster MembersUnderstanding ClusterCATS server modesClusterCATS lets you move cluster members into modes of operation de

Strany 26 - Avoiding common bottlenecks

Changing active/passive settings 111Changing active/passive settingsAll cluster members are added to a cluster with the ClusterCATS Server in active s

Strany 27 - • “What is DNS?” on page 17

112 Chapter 5 Maintaining Cluster MembersChanging active/passive settings in UNIXTo change a cluster member’s state:1 In ClusterCATS Web Explorer,

Strany 28 - Zones and domains

Changing restricted/unrestricted settings 113Changing restricted/unrestricted settingsClusterCATS lets you stop a cluster member from receiving HTTP r

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114 Chapter 5 Maintaining Cluster MembersRestricting/unrestricting servers in UNIXTo change restriction settings for a cluster member:1 In ClusterC

Strany 30

Using maintenance mode (Windows only) 115Using maintenance mode (Windows only)Putting a ClusterCATS Server in maintenance mode lets you remove a serve

Strany 31

116 Chapter 5 Maintaining Cluster MembersTo put a cluster member in maintenance mode:1 In ClusterCATS Explorer, select a cluster member to update.2

Strany 32

Using maintenance mode (Windows only) 1176 Click the BT Service Status button to display the Manage ClusterCATS Services dialog box:7 Select the Stopp

Strany 33 - What is website availability?

118 Chapter 5 Maintaining Cluster MembersUpdating a cluster member (Windows only)Periodically you will need to update software or content that resi

Strany 34 - Common failures

Updating a cluster member (Windows only) 1198 To initially limit the amount of HTTP traffic sent to the server, return to ClusterCATS Explorer and rec

Strany 35 - Failover considerations

ClusterCATS overview 3The following table introduces the ClusterCATS capabilities: Detailed overviewApplication and server load managementClusterCATS

Strany 36

120 Chapter 5 Maintaining Cluster MembersResetting cluster members ClusterCATS includes a utility for resetting cluster members to their precluster

Strany 37

121CHAPTER 6ClusterCATS UtilitiesClusterCATS ships with scriptable command-line utilities for configuring, administering, and troubleshooting ClusterC

Strany 38 - What is clustering?

122 Chapter 6 ClusterCATS UtilitiesUsing btadminbtadmin is a scriptable utility installed on each server in a cluster. It provides most of the func

Strany 39 - • It uses proven technology

Using btadmin 123The following sections describe each of these options.[start | stop | restart <daemon>]You can start, stop and restart the foll

Strany 40

124 Chapter 6 ClusterCATS UtilitiesYou can enable, disable, and configure the following ClusterCATS options using the btadmin utility: The followin

Strany 41

Using bt-start-server and bt-stop-server (UNIX only) 125Using bt-start-server and bt-stop-server (UNIX only)The bt-start-server and bt-stop-server uti

Strany 42

126 Chapter 6 ClusterCATS UtilitiesUsing btcfgchkThe btcfgchk utility is a network management tool that displays information about your IP and DNS

Strany 43 - Installing ClusterCATS

Using btcfgchk 127(PRT record) translates an IP address to its host name. ClusterCATS expects the mapping to be one-to-one (one host name to one IP ad

Strany 44 - Before you install

128 Chapter 6 ClusterCATS UtilitiesHost name not found in any reverse mappingProbable forward mapping misconfiguration for <hostname>For each

Strany 45

Using hostinfo 129Using hostinfoThe hostinfo utility is a network management tool that displays information about a domain name. Use it to analyze and

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4 Chapter 1 Before You BeginSession state management and failoverFor some applications, it is important that a user session is completed on one ser

Strany 47

130 Chapter 6 ClusterCATS UtilitiesUsing sniffThe sniff utility is a network management tool that displays the packets that a specific network inte

Strany 48 - Configuring firewalls

131CHAPTER 7Optimizing ClusterCATSClusterCATS provides enhanced capabilities that let you customize your ClusterCATS implementation. This chapter desc

Strany 49 - Analyzing web server content

132 Chapter 7 Optimizing ClusterCATSClusterCATS dynamic IP addressing (Windows only)This section describes how to enable ClusterCATS dynamic IP add

Strany 50

ClusterCATS dynamic IP addressing (Windows only) 133Benefits of ClusterCATS dynamic IP addressingThere are several benefits to your using ClusterCATS

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134 Chapter 7 Optimizing ClusterCATS5 Open the Advanced IP Addressing dialog box by right-clicking Network Neighborhood. Select Properties. On the

Strany 52

ClusterCATS dynamic IP addressing (Windows only) 13512 Reinstall products that are configured as part of IIS, including JRun/ColdFusion and ClusterCAT

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136 Chapter 7 Optimizing ClusterCATS6 Open the Advanced IP Addressing dialog box by right-clicking Network Neighborhood, and select Properties. On

Strany 54

Using server failover 137Using server failoverThe ability to fail over servers that have become unavailable to redundant servers is a cornerstone of a

Strany 55 - After you install

138 Chapter 7 Optimizing ClusterCATSConfiguring load-balancing metricsYou have the option to customize the load-balancing metrics of web servers cl

Strany 56

Configuring load-balancing metrics 139Load typesThe page ClusterCATS probes for load-balancing options, getsimpleload.jsp for JRun and getsimpleload.c

Strany 57 - Configuring Clusters

ClusterCATS overview 5ClusterCATS product configurationsClusterCATS includes a comprehensive core set of features and offers several add-on options fo

Strany 58 - ClusterCATS Server

140 Chapter 7 Optimizing ClusterCATSTroubleshooting the load-balancing metricsIf ClusterCATS gets an exception every time it processes getsimpleloa

Strany 59

141INDEXAA records 19absolute hyperlinks 72active mode 110active/passive modechanging 111changing in UNIX 112changing in Windows 111adding cluster mem

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142 Indexload thresholds 66maintenance mode 115maintenance support 60moving to cluster 120peak load threshold 66preclustered state 120probes and monit

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Index 143optimizing with dynamic IP addressing 133parallel servers 26persistent sessions 74static vs. dynamic IP addressing 137systems monitoring 26We

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144 Indexmonitoring load status 68monitors 77, 84adding new 78, 85removing in Windows 81, 88Nname servers 19Netscape, Web Explorer considerations 50NT

Strany 63

Index 145sniffsample output 130syntax 130using 130software-based clusteringadvantages 31considerations 31solutions 30state management 13static vs. dyn

Strany 65 - Creating clusters 55

6 Chapter 1 Before You BeginClusterCATS componentsClusterCATS consists of these primary components:• Server Resides on each computer in a cluster.

Strany 66

System requirements 7System requirementsThis section describes the platforms on which the ClusterCATS components run and their minimum system requirem

Strany 67 - Creating clusters 57

8 Chapter 1 Before You BeginClusterCATS Explorer and Web Explorer system requirementsYou can install the ClusterCATS Explorer or Web Explorer compo

Strany 68

9CHAPTER 2Scalability and Availability OverviewThis chapter describes the concepts involved in achieving scalable and highly available web application

Strany 69

TrademarksAfterburner, AppletAce, Attain, Attain Enterprise Learning System, Attain Essentials, Attain Objects for Dreamweaver, Authorware, Authorware

Strany 70 - Creating clusters in UNIX

10 Chapter 2 Scalability and Availability OverviewWhat is scalability?As an administrator, you probably hear about the importance of having web ser

Strany 71 - 3 Click OK

What is scalability? 11Linear scalabilityPerfect scalability — excluding cache initializations — is linear. Linear scalability, relative to load, mean

Strany 72 - Removing clusters

12 Chapter 2 Scalability and Availability OverviewLoad managementLoad management refers to the method by which simultaneous user requests are distr

Strany 73 - Adding cluster members

Successful scalability implementations 13Successful scalability implementationsAchieving scalable web servers is not a trivial task. There are various

Strany 74

14 Chapter 2 Scalability and Availability OverviewWeb developers must think through the user scenarios in which application session and state are a

Strany 75 - Removing cluster members

Successful scalability implementations 15Application partitioningThe way an application is partitioned and deployed dramatically affects its ability t

Strany 76 - Server load thresholds

16 Chapter 2 Scalability and Availability Overviewcleanly display all technologies, such as cascading style sheets (CSS), Java applets, and frames,

Strany 77 - Server load thresholds 67

Successful scalability implementations 17• Network connectivity and bandwidth — consider the type of network your application will run on (LAN/WAN/Int

Strany 78

18 Chapter 2 Scalability and Availability OverviewTo understand why, let’s look at the e-commerce example. Even if you have planned ahead and set u

Strany 79 - Server load thresholds 69

Successful scalability implementations 19The following figure shows these concepts:DNS servers store information about the domain name space and are r

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CONTENTSABOUT THIS BOOK . . . . . . . . . . . . . . . . . . . . . . . . . . . VIIDeveloper resources . . . . . . . . . . . . . . . . . . . . . . . . .

Strany 81 - Server load thresholds 71

20 Chapter 2 Scalability and Availability OverviewThe DNS entries would look like the following::To ensure that your site lookups and translations

Strany 82 - Session-aware load balancing

Successful scalability implementations 21hitting your web server. By using the software in conjunction with your defined benchmarks and formal test pl

Strany 83

22 Chapter 2 Scalability and Availability OverviewLoad-testing considerationsBefore starting your load testing, consider the following:• Define ben

Strany 84 - Session swapping overview

What is website availability? 23What is website availability?It is critical to design, develop, test, and deploy web applications so they can scale we

Strany 85

24 Chapter 2 Scalability and Availability OverviewFor JRun and ColdFusion web applications, it is particularly important that the servers remain as

Strany 86

What is website availability? 25Website availability scenarioImagine that you have just built a robust, interactive e-commerce website on which you pl

Strany 87 - Using ColdFusion probes

26 Chapter 2 Scalability and Availability OverviewHardware planningAs indicated in the availability example above, you must acquire all necessary h

Strany 88

What is website availability? 27However, before the analysis and repair can occur, the administrator must be notified. Whatever failover system you pu

Strany 89

28 Chapter 2 Scalability and Availability OverviewCreating scalable and highly available sitesWhen you understand the issues of scalability and ava

Strany 90

Creating scalable and highly available sites 29Hardware-based clustering solutionsA common and reliable hardware-based clustering solution is a packet

Strany 91 - To remove a ColdFusion probe:

iv Contents CHAPTER 3 Installing ClusterCATS . . . . . . . . . . . . . . . . . . . . . . . . 33Before you install . . . . . . . . . . . . . . . .

Strany 92

30 Chapter 2 Scalability and Availability Overview• There are no recurrent licensing fees• It is semi-intelligent; routers can load balance in a ro

Strany 93 - Using ColdFusion probes 83

Creating scalable and highly available sites 31AdvantagesThe following benefits make a software-based clustering solution attractive:• Relatively low

Strany 94 - Using JRun probes

32 Chapter 2 Scalability and Availability OverviewCombining hardware and software clustering solutionsInstead of having to choose either a hardware

Strany 95 - Using JRun probes 85

33CHAPTER 3Installing ClusterCATSBefore installing ClusterCATS, you must make many important decisions about the architecture of your website. Use the

Strany 96

34 Chapter 3 Installing ClusterCATSBefore you installBefore installing ClusterCATS and creating server clusters, you must perform the following pre

Strany 97

Before you install 35The primary DNS server contains tables of forward and reverse name translations. For example, forward translation entries (A reco

Strany 98 - To remove a JRun probe:

36 Chapter 3 Installing ClusterCATSThe following diagram shows this process:Configuring your primary DNS serverYou must configure DNS so the forwar

Strany 99 - To add a new JRun probe:

Before you install 37Using ClusterCATS with round-robin DNS For high-volume sites, you should use round robin DNS to initially distribute requests to

Strany 100

38 Chapter 3 Installing ClusterCATSRound-robin DNS distributes the initial domain-level requests across all four servers. Thereafter, ClusterCATS d

Strany 101

Before you install 39from behind another firewall, you must open both ports so the ClusterCATS Explorer can communicate with the cluster.The following

Strany 102 - Load-balancing devices

C o n t e n t s vLoad-balancing devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

Strany 103 - • dynamic-feedback -retry

40 Chapter 3 Installing ClusterCATSConsidering domain controllers (Windows NT only)If you use Windows NT Domain server authentication, each web ser

Strany 104 - Product drop-down list

Installing ClusterCATS 41Installing ClusterCATSClusterCATS is a separate installation package from the JRun server installation program. You must inst

Strany 105

42 Chapter 3 Installing ClusterCATSThe following table describes your options: 6 In the Server Fail-Over dialog box, to enable this server to assum

Strany 106

Installing ClusterCATS 433Review the license.txt file that is supplied with ClusterCATS. If you agree with the licensing terms, enter Yes at the promp

Strany 107 - Load-balancing devices 97

44 Chapter 3 Installing ClusterCATSIf you are configuring ClusterCATS with Netscape and selected Yes, you are prompted to decide which servers in t

Strany 108

After you install 45After you installWhen you have successfully installed ClusterCATS on all members of the cluster and any administrative computers,

Strany 109

46 Chapter 3 Installing ClusterCATS

Strany 110 - Administrator e-mail options

47CHAPTER 4Configuring ClustersWhen you have configured your website and installed ClusterCATS, use the procedures in this chapter to create and confi

Strany 111

48 Chapter 4 Configuring ClustersIntroduction to ClusterCATS AdministrationClusterCATS consists of these components:• ClusterCATS Server• ClusterCA

Strany 112

Introduction to ClusterCATS Administration 49Note: You can run the ClusterCATS Explorer from any server in the cluster, or you can run it remotely. Th

Strany 113 - Administering security

vi Contents CHAPTER 7 Optimizing ClusterCATS . . . . . . . . . . . . . . . . . . . . . . .131ClusterCATS dynamic IP addressing (Windows only) . . .

Strany 114

50 Chapter 4 Configuring Clusters• Monitor the load hitting the server via a graphical display; the server’s load statistics are only displayed tex

Strany 115 - Administering security 105

Introduction to ClusterCATS Administration 51 AuthUserFile /usr/local/apache/conf/users require user admin </D

Strany 116

52 Chapter 4 Configuring ClustersClusterCATS Server AdministratorThe ClusterCATS Server Administrator is a Windows-based utility that lets you perf

Strany 117 - Administering security 107

Introduction to ClusterCATS Administration 53btadminbtadmin is a scriptable utility that lets you perform server-specific maintenance activities for e

Strany 118

54 Chapter 4 Configuring ClustersCreating clustersIf you have performed the tasks described in “Before you install” on page 34 and you have success

Strany 119 - Maintaining Cluster Members

Creating clusters 55The Create New Cluster dialog box appears:3 Enter a name for your cluster and click Next.Make your cluster names logically consist

Strany 120

56 Chapter 4 Configuring Clusters4 Click Add to add available web servers to your cluster.The Add New Server to Cluster dialog box appears:5 Enter

Strany 121

Creating clusters 5710 To use the default load threshold settings, click Next and go to step 13. If you do not want to use the defaults, select the se

Strany 122

58 Chapter 4 Configuring Clustersmanually change the few recipients that are different. If there are multiple recipients for one alert event, separ

Strany 123

Creating clusters 59Manually creating clustersIf you do not want to create your clusters using the Cluster Setup Wizard, you can create them manually.

Strany 124

viiABOUT THIS BOOKUsing ClusterCATS describes how to use ClusterCATS, the clustering technology that provides load-balancing and failover services to

Strany 125

60 Chapter 4 Configuring Clusters4 Click OK.The cluster appears below the Cluster Manager icon in the ClusterCATS Explorer left pane. To manually a

Strany 126

Creating clusters 612 Add a cluster using the fields as described in the following table: 3 Click OK.ClusterCATS creates the cluster and displays its

Strany 127

62 Chapter 4 Configuring ClustersRemoving clustersTo delete a cluster, you must delete each member from the cluster individually, using the procedu

Strany 128

Adding cluster members 63Adding cluster membersYou can add servers to a cluster at any time. This section describes the following:• “Adding cluster me

Strany 129

64 Chapter 4 Configuring ClustersAdding cluster members in UNIXUse the ClusterCATS Web Explorer to add cluster members.To add a cluster member to a

Strany 130 - Resetting cluster members

Removing cluster members 65Removing cluster membersYou can remove servers from a cluster at any time. This section describes the following:• “Removing

Strany 131 - ClusterCATS Utilities

66 Chapter 4 Configuring ClustersServer load thresholdsClusterCATS ensures that your web applications remain available and running at optimum perfo

Strany 132 - Using btadmin

Server load thresholds 67The server’s Properties dialog box appears:3 Click the Load tab.4 Enter a numeric value (less than 100%) in the first Load Ma

Strany 133

68 Chapter 4 Configuring ClustersViewing a cluster’s load statusJRun/ColdFusion reports its load data directly to ClusterCATS. You can view the loa

Strany 134

Server load thresholds 69The Server Load dialog box appears:3 Use your mouse to drag the peak load threshold (red) up or down.As you move the line, th

Strany 135

viii About This BookDeveloper resourcesMacromedia, Inc. is committed to setting the standard for customer support in developer education, document

Strany 136 - Using btcfgchk

70 Chapter 4 Configuring Clusters3 Click OK.The Cluster Member List page appears. If you get an "Error: Server <cluster_member_name> cou

Strany 137

Server load thresholds 71The selected server’s Server Properties page appears:7 Click the Administration link under Server Attributes.The Server Admin

Strany 138

72 Chapter 4 Configuring ClustersSession-aware load balancingManaging a web application’s state in a clustered environment can be challenging. By d

Strany 139 - Using hostinfo

Session-aware load balancing 733 Click OK.The Cluster Member List page appears:4 Click the Administration link under Cluster Attributes.The Cluster Ad

Strany 140 - Using sniff

74 Chapter 4 Configuring ClustersPersistent session failover in JRun JRun can be configured to enable session persistence, meaning that all session

Strany 141 - Optimizing ClusterCATS

Persistent session failover in JRun 75To enable session swapping on Windows: 1 Edit the registry (using regedit) and open the following key: HKEY_LOCA

Strany 142

76 Chapter 4 Configuring ClustersUsing JDBC for session swappingTo use JDBC for session swapping, the JRun server's local.properties file shou

Strany 143

Using ColdFusion probes 77Using ColdFusion probesClusterCATS provides load-balancing and failover support for your web applications in two ways. First

Strany 144

78 Chapter 4 Configuring ClustersTo add a new monitor and ColdFusion probe:1 Open the ClusterCATS Explorer and select a server.2 Select Server >

Strany 145

Using ColdFusion probes 794 Click the New Probe button .The ColdFusion Web Application Probe settings dialog box appears:5 Configure the application

Strany 146

About Macromedia documentation ixAbout Macromedia documentationMacromedia documentation is designed to provide support for the complete spectrum of pa

Strany 147 - Using server failover

80 Chapter 4 Configuring Clusters6 Click Register to create the probe.7 Close all open dialog boxes.Icons for the monitor and probe appear under th

Strany 148 - Overview of metrics

Using ColdFusion probes 814 Click the New Probe button .The ColdFusion Web Application Probe settings dialog box appears:5 Configure the application

Strany 149 - Output variables

82 Chapter 4 Configuring Clusters9 To create a new probe, click New. The ColdFusion Application Probe page appears. If this is the first probe for

Strany 150

Using ColdFusion probes 8311 Click Register to create the probe. ClusterCATS begins to test the selected server immediately.Editing and removing ColdF

Strany 151

84 Chapter 4 Configuring ClustersUsing JRun probesClusterCATS provides load-balancing and failover support for your web applications in two ways. F

Strany 152 - 142 Index

Using JRun probes 85To add a new monitor and JRun probe:1 Open the ClusterCATS Explorer and select a server.2 Select Server > New Monitor or right-

Strany 153

86 Chapter 4 Configuring Clusters4 Click the New Probe button .The JRun Application Probe settings dialog box appears:5 Configure the application

Strany 154

Using JRun probes 876 Click Register to create the probe.7 Close all open dialog boxes.Icons for the monitor and probe appear under the Monitor Manage

Strany 155

88 Chapter 4 Configuring ClustersThe monitor’s Properties dialog box appears:3 Click the New Probe button .The JRun Application Probe settings dia

Strany 156 - 146 Index

Using JRun probes 89Adding JRun probesTo add a new JRun probe:1 In the ClusterCATS Web Explorer, click the Show Cluster link. The Show Cluster page ap

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