VERITAS Cluster Server Agent 1.0 for IBM HTTP Server

Transcription

1 VERITAS Cluster Server Agent 1.0 for IBM HTTP Server Installation and Configuration Guide Solaris February 2003

2 Disclaimer The information contained in this publication is subject to change without notice. VERITAS Software Corporation makes no warranty of any kind with regard to this manual, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose. VERITAS Software Corporation shall not be liable for errors contained herein or for incidental or consequential damages in connection with the furnishing, performance, or use of this manual. Copyright Copyright VERITAS Software Corporation. All Rights Reserved. VERITAS is a registered trademark of VERITAS Software Corporation in the U.S. and other countries. The VERITAS logo and VERITAS Cluster Server are trademarks of VERITAS Software Corporation. All other trademarks or registered trademarks are the property of their respective owners. VERITAS Software Corporation 350 Ellis Street Mountain View, CA USA Phone (650) Fax (650) VCS Agent for IBM HTTP Server: Installation and Configuration Guide 2

3 Table of Contents Table of Contents... 3 Preface... 4 Technical Support... 4 Conventions... 4 Introduction... 5 Version Numbers and Operating Systems... 5 About the Agent... 5 Prerequisites... 6 Installing the Agent Software... 6 Adding the Agent With Cluster Manager... 7 Configuring an HTTP Resource... 8 VProIBMHTTP Resource Type... 8 Type Definition Sample Configuration Sample Service Group Configuration Binding the HTTP Server to an IP and Port Removing the Agent Software VCS Agent for IBM HTTP Server: Installation and Configuration Guide 3

4 Preface This document provides instructions for installing and configuring the VERITAS Cluster Server (VCS) Agent for IBM HTTP Server. For information about VERITAS Cluster Server, refer to the VERITAS Cluster Server User s Guide. Technical Support For assistance with this VERITAS product, or for information regarding VERITAS service packages, contact Technical Support at (800) (U.S. and Canada). You may also contact Technical Support via at support@veritas.com. For Customers Outside U.S. and Canada From Europe, the Middle East, or Asia, visit the Technical Support Web site at for a list of each country s contact information. Conventions Typeface courier courier (bold) italic Usage Computer output, files, attribute names, device names, and directories User input and commands, keywords in grammar syntax New terms, titles, emphasis italic Variables Symbol Usage % C shell prompt $ Bourne/Korn shell prompt # Super user prompt (for all shells) VCS Agent for IBM HTTP Server: Installation and Configuration Guide 4

5 Introduction Welcome to the VERITAS Cluster Server (VCS) Agent for IBM HTTP Server. This guide describes the agent, its modes of operation, and its attributes. It also describes how to install and configure the agent. The guide assumes the reader understands the primary components and basic functionality of VCS. It also assumes a basic understanding of the IBM HTTP Server architecture and configuration process. Version Numbers and Operating Systems VCS Agent 1.0 for IBM HTTP Server has been tested with VCS 3.5 on Solaris 8. Development and testing of this agent was performed using IBM HTTP Server Although not formally tested, this agent should function properly with VCS 2.0. The IBM HTTP Server agent was developed using the VPro Agent Framework. The VPro Agent Framework, developed by VERITAS, is a set of libraries that contain common, reusable functions such as process identification, logging, system calls, and many others. The VPro Agent Framework is included and installed with VCS 3.5; thus, the agent can be used immediately after it is installed in a VCS 3.5 environment. The VPro Agent Framework is not included with VCS 2.0. To use this agent with VCS 2.0, contact VERITAS Enterprise Consulting Services to obtain a copy of the VPro Agent Framework. About the Agent The VCS Agent for IBM HTTP Server consists of resource type declarations and agent scripts. They are described below. IBM HTTP Server Agent: VProIBMHTTP Description Operations Brings an HTTP server online, monitors the processes, and brings the HTTP server offline. Online: Starts an HTTP server by executing the script RootDir/bin/apachectl with the argument start. The script is created during the HTTP Server installation process. If a file is specified by attribute EnvFile, it will be sourced before executing apachectl. Offline: Stops an HTTP server by executing the script RootDir/bin/apachectl with the argument stop. The script is created during the HTTP Server installation process. If a file is specified by attribute EnvFile, it will be sourced before executing apachectl. Monitor: Monitors the state of an HTTP server by first checking if the processes exist and then performing an optional, secondary state check. Clean: Removes HTTP server system resources that may remain after an unsuccessful attempt to online or offline an HTTP server. These resources include the parent HTTP daemon and all child HTTP daemons. VCS Agent for IBM HTTP Server: Installation and Configuration Guide 5

6 Detecting Application Failure The agent provides two methods to evaluate the state of an IBM HTTP Server instance. The first state check is mandatory and the second is optional. The first check determines the state of the HTTP server by searching for the existence of the parent HTTP daemon (owned by root) and for at least one child HTTP daemon. If the parent process and at least one child do not exist, VCS reports the resource as offline. If they do exist, and if the agent attribute SecondLevelMonitor is set to true (1), then a socket connection is established with the HTTP server using the values specified by agent attributes Host and Port. Once connected, the agent issues an HTTP request to the server to test its ability to respond. If the HTTP server responds with a return code between 0 and 408, the agent considers the server online. If the server fails to respond or returns any other code, the agent considers the server offline. Prerequisites Install and configure VCS. If necessary, review the VERITAS Cluster Server Installation Guide. Install and configure one or more IBM HTTP Server instances. Carefully review the configuration requirements and suggestions explained in the remaining sections of this document. Verify that all systems have enough resources to run the IBM HTTP Server instances. Installing the Agent Software Perform the following steps on each system in the cluster. 1. Log in as root. 2. Copy the agent installation file to a temporary directory. 3. Change to the temporary directory created in the previous step, extract the contents of the installation file, and then change to the pkgs directory. # cd /temp_directory # uncompress file_name.tar.z # tar xvf file_name.tar # cd pkgs 4. Install the package. Follow the package-add prompts and select the package labeled VCS Agent for IBM HTTP Server. Ignore other displayed packages. # pkgadd d. The following packages are available: 1 VRTSvcsht VERITAS VCS Agent for IBM HTTP (optional) 1.0 Select package(s) you wish to process (or 'all' to process all packages). (default: all) [?,??,q]: 1 Processing package instance <VRTSvcsht> from </tmp/http> VERITAS VCS Agent for IBM http (optional) 1.0 Copyright(C) VERITAS Software Corporation. All Rights Reserved VCS Agent for IBM HTTP Server: Installation and Configuration Guide 6

7 ## Processing package information. ## Processing system information. ## Verifying package dependencies. ## Verifying disk space requirements. ## Checking for conflicts with packages already installed. ## Checking for setuid/setgid programs. This package contains scripts which will be executed with super-user permission during the process of installing this package. Do you want to continue with the installation of <VRTSvcsht> [y,n,?] y Installing VERITAS VCS Agent for IBM HTTP as <VRTSvcsht> ## Installing part 1 of 1. /etc/vrtsvcs/conf/sample_vproibmhttp/vproibmhttptypes.cf /etc/vrtsvcs/conf/sample_vproibmhttp/main.cf /opt/vrtsvcs/bin/vproibmhttp/vproibmhttpagent <symbolic link> /opt/vrtsvcs/bin/vproibmhttp/clean <symbolic link> /opt/vrtsvcs/bin/vproibmhttp/monitor /opt/vrtsvcs/bin/vproibmhttp/offline <symbolic link> /opt/vrtsvcs/bin/vproibmhttp/online <symbolic link> /opt/vrtsvcs/lib/perl5/.vcsagntfw/lib/vproibmhttp.pm /opt/vrtsvcs/messages/en/vrtsvcssunvproibmhttp.bmc [ verifying class <none> ] ## Executing postinstall script. bmcmap:10005:bmc map created Installation of <VRTSvcsht> was successful. The following packages are available: 1 VRTSvcsht VERITAS VCS Agent for IBM HTTP (optional) 1.0 Select package(s) you wish to process (or 'all' to process all packages). (default: all) [?,??,q]: q Adding the Agent With Cluster Manager To use the IBM HTTP Server agent without stopping and restarting VCS, import the VProIBMHTTPTypes.cf file into the VCS engine by performing the following steps in Cluster Manager (the VCS graphical user interface). 1. Start Cluster Manager. 2. Click on the File menu and select Import Types. 3. In the Import Types dialog box, select the following file: /etc/vrtsvcs/conf/sample_vproibmhttp/vproibmhttptypes.cf 4. Click the Import button. 5. Save the VCS configuration. At this point, the IBM HTTP Server types have been imported to the VCS engine. HTTP Server resources may now be created. For detailed information about using the VCS Cluster Manager, refer to the VERITAS Cluster Server User s Guide. VCS Agent for IBM HTTP Server: Installation and Configuration Guide 7

8 Configuring an HTTP Resource After installing the agent package and importing the configuration file, a HTTP Server resource can be created and configured by using VCS Cluster Manager. Before you configure a resource, review the following table that describes the HTTP Server resource type and its attributes. The resource type definition file and a sample main.cf configuration are also shown for reference. VProIBMHTTP Resource Type Attribute ActivationKey Definition Type: String-scalar Description: License key that enables the use of the agent for each resource. Obtain the key from your VERITAS sales representative. The agent will not function properly without a valid key. Example: A Default Value: No default value EnvFile Type: String-scalar Description: Full path and file name of the file that is sourced prior to executing RootDir/bin/apachectl. VERITAS recommends using EnvFile to establish desired environment variables rather than relying on user root s profile. Specifying this attribute is optional. If EnvFile is specified, the login shell for user root must be either Bourne or Korn. Example: /web1/ibmhttp/bin/setenv Default Value: No default value Host Type: String-scalar Description: Virtual host name assigned to the HTTP Server instance. The host name is used in second-level monitoring to establish a socket connection with the HTTP server. Specifying this attribute is required only if SecondLevelMonitor is set to 1 (true). Example: web1.veritas.com Default Value: No default value MonitorGetTimeout Type: Integer Description: Number of seconds the agent waits for the second-level monitor program (HTTP GET) to return before timing-out and canceling its execution. The agent evaluates the resource as offline if the second-level monitor program times-out; thus, the value should be sufficiently high to allow second-level monitoring enough time to complete, but the value should also be less than the value specified by the agent s MonitorInterval attribute. Specifying this attribute is required. Example: 30 Default Value: 30 VCS Agent for IBM HTTP Server: Installation and Configuration Guide 8

9 Attribute Port Definition Type: Integer Description: Port number on which the HTTP Server instance is listening. The port number is used in second-level monitoring to establish a socket connection with the HTTP server. Specifying this attribute is required only if SecondLevelMonitor is set to 1 (true). Example: 80 Default Value: 80 RootDir Type: String-scalar Description: Identifies the HTTP Server instance root installation directory. RootDir is used to locate the script apachectl, which starts and stops an HTTP instance. RootDir is also used to uniquely identify an instance s processes, which requires RootDir to be unique compared to RootDir for all other HTTP instances in the cluster. The value specified by RootDir may not be longer than 60 characters. Specifying this attribute is required. Example: /web1/ibmhttp Default Value: No default value SecondLevelMonitor Type: Boolean Description: Enables second-level monitoring for the resource. Second-level monitoring is a deeper, more thorough state check of the IBM HTTP Server performed by issuing an HTTP GET request on the web server s root directory. Valid attribute values are 1 (true) and 0 (false). Specifying this attribute is required. Example: 0 Default Value: 0 VProLogLevel Type: String-scalar Description: Controls the logging detail performed by the agent for a specific instance of a resource. Valid values are as follows: ERROR WARN INFO TRACE Only error level messages are logged. Error and warning level messages are logged. Error, warning, and informational level messages are logged. Error, warning, informational, and trace level messages are logged. Trace logging is very verbose and should only be used during initial configuration or to facilitate troubleshooting. Example: INFO Default Value: INFO VCS Agent for IBM HTTP Server: Installation and Configuration Guide 9

10 Type Definition type VProIBMHTTP ( static str ArgList[] = { VProLogLevel, ActivationKey, State, IState, RootDir, EnvFile, MonitorGetTimeout, Host, Port, SecondLevelMonitor } NameRule = "" str VProLogLevel = INFO str ActivationKey str RootDir str EnvFile int MonitorGetTimeout = 30 str Host int Port = 80 boolean SecondLevelMonitor = 0 ) Sample Configuration The following is an excerpt from a main.cf file that included an HTTP Server resource. The activation key is only an example; it will not enable the HTTP Server resource. VProIBMHTTP Web1_http ( ActivationKey = A RootDir = "/web1/ibmhttp" Host = "web1.veritas.com" Port = 80 MonitorGetTimeout = 30 SecondLevelMonitor = 1 ) VCS Agent for IBM HTTP Server: Installation and Configuration Guide 10

11 Sample Service Group Configuration Figure 1 depicts a service group that supports a single IBM HTTP server. At a minimum, the service group will require disk and network resources to support the HTTP server resource. The disk group is the VERITAS Volume Manager disk group that contains the volume and the file system (mount resource) that will house the HTTP server installation files (i.e. the files in RootDir). The disk group is created from shared disk so that it can be imported into any system in the cluster. In non-clustered configurations, an HTTP server is commonly installed on internal system disks, which couples the instance to one system and prevents the HTTP server from being started on another system. Installing the HTTP server on shared disk decouples the instance and allows it to run on any system in the cluster. This flexibility is important when clustering an application. Prior to IBM HTTP Server version , the installation program automatically installed the HTTP server in the directory /opt/ibmhttpd, which normally placed the install files on an internal system disk. Beginning with IBM HTTP Server , the installation directory is a configurable option when performing a custom installation. Use this option to install the HTTP server on shared disk. The network interface resource is the network card through which the HTTP server communicates. The virtual IP is the IP address dedicated to the HTTP server. External services, programs, and clients use this address to communicate with this HTTP server instance; thus, the HTTP server must be configured to bind to this virtual IP address. IBM HTTP Server Virtual IP Mount Network Interface Disk Group Figure 1 - Service group supporting an IBM HTTP server Binding the HTTP Server to an IP and Port To prevent communication conflicts if multiple HTTP server instances are running on the same system, configure each HTTP server instance to bind to a unique IP address and port number (i.e. to listen on a unique IP address and port). This can be achieved by configuring a Listen property in the HTTP server configuration file RootDir/conf/httpd.conf. Syntax: Listen VirtualIPAddress:Port Example: Listen :8080 Also, be sure to set the property ServerName in the configuration file to the virtual IP host name assigned to the HTTP server. VCS Agent for IBM HTTP Server: Installation and Configuration Guide 11

12 Syntax: ServerName VirtualIPHostname Example: ServerName web1.veritas.com Refer to the IBM HTTP Server documentation for more information about these entries in httpd.conf. Removing the Agent Software Follow the steps below to remove the IBM HTTP Server agent from VCS. These steps must be performed while the cluster is started. 1. Remove all resources from the cluster that use the IBM HTTP Server agent. 2. Set the VCS configuration mode to read/write by typing the following command from any system in the cluster (must be logged in as user root): # haconf -makerw 3. Remove the agent from the VCS configuration by typing the following command from any system in the cluster. This will remove the include statement for the agent from main.cf, but the agent s type file will not be removed. # hatype -delete VProIBMHTTP 4. Set the VCS configuration mode to read-only by typing the following command from any system in the cluster: # haconf dump -makero 5. On each node in the cluster, use the package remove program to uninstall the VCS agent. # pkgrm VRTSvcsht The following package is currently installed: Removal of <VRTSvcsht> was successful. VCS Agent for IBM HTTP Server: Installation and Configuration Guide 12