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Oracle® Clusterware Administration and Deployment Guide
11g Release 2 (11.2)

Part Number E16794-06
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B Oracle Clusterware Resource Reference

This appendix is a reference for Oracle Clusterware resources. It includes descriptions and usage examples of all resource attributes and a detailed description and examples of action scripts.

This appendix includes the following topics:


Resource Attributes

This section lists and describes attributes used when you register applications as resources in Oracle Clusterware. Use these attributes with the crsctl add resource command, as follows:

$ crsctl add resource resource_name -type resource_type
{[-attr "attribute_name='attribute_value', attribute_name='attribute_value'
, ..."] | [-file file_name]}

List attribute-value pairs in a comma-delimited list after the -attr flag and enclose the value of each attribute in single quotation marks (''). Some resource attributes you cannot configure and are read only.

Alternatively, you can create a text file that contains the attribute-value pairs. For example:

PLACEMENT=favored
HOSTING_MEMBERS=node1 node2 node3
RESTART_ATTEMPTS@CARDINALITYID(1)=0
RESTART_ATTEMPTS@CARDINALITYID(2)=0
FAILURE_THRESHOLD@CARDINALITYID(1)=2
FAILURE_THRESHOLD@CARDINALITYID(2)=4
FAILURE_INTERVAL@CARDINALITYID(1)=300
FAILURE_INTERVAL@CARDINALITYID(2)=500
CHECK_INTERVAL=2
CARDINALITY=2

This section includes the following topics:


Configurable Resource Attributes

This section describes the following resource attributes that you can configure when registering an application as a resource in Oracle Clusterware:

Note:

Values for the all attributes must be in lowercase. Attribute names must be in uppercase.

ACL

Defines the owner of a resource and the access privileges granted to various operating system users and groups. The resource owner defines the operating system user of the owner and its privileges. You configure this optional attribute when you create a resource. If you do not configure this attribute, then the value is based on the identity of the process creating a resource. You can change the value of the attribute if such a change is allowed based on the existing privileges of the resource.

In the string:

By default, the identity of the client that creates a resource is the owner. Also by default, root, and the user specified in owner have full privileges. You can grant required operating system users and operating system groups their privileges by adding the following lines to the ACL attribute:

user:user_name:rwx
group:group_name:rwx

Usage Example

ACL=owner:user_1:rwx,pgrp:osdba:rwx,other::r-

ACTION_SCRIPT

An absolute file name that includes the path and file name of an action script. The agent specified in the AGENT_FILENAME attribute calls the script specified in the ACTION_SCRIPT attribute.

Usage Example

ACTION_SCRIPT=fully_qualified_path_to_action_script

ACTIVE_PLACEMENT

When set to 1, Oracle Clusterware uses this attribute to reevaluate the placement of a resource during addition or restart of a cluster server. For resources where PLACEMENT=favored, Oracle Clusterware may relocate running resources if the resources run on a non-favored server when a favored one joins the cluster.

Usage Example

ACTIVE_PLACEMENT=1

AGENT_FILENAME

A fully qualified file name of an agent program that a resource type uses to manage its resources. Every resource type must have an agent program to manage its resources. Resource types use agent programs by either specifying a value for this attribute or inheriting it from their base resource type. There are two script agents included with Oracle Clusterware 11g release 2 (11.2): application and scriptagent. Oracle Clusterware uses the application script agent for resources of the deprecated application resource type. The default value for this attribute is scriptagent.

Usage Example

AGENT_FILENAME=%Grid_home%/bin/application

AUTO_START

Indicates whether Oracle Clusterware automatically starts a resource after a cluster server restart. Valid AUTO_START values are:

CARDINALITY

The number of servers on which a resource can run, simultaneously. This is the upper limit for resource cardinality.

Usage Example

CARDINALITY=1

CHECK_INTERVAL

The time interval, in seconds, between repeated executions of the check action. Shorter intervals enable more frequent checks but also increase resource consumption if you use the script agent. Use an application-specific agent to reduce resource consumption.

Usage Example

CHECK_INTERVAL=60

DEGREE

The number of instances of a cluster resource that can run on a single server.

Usage Example

DEGREE=1

DESCRIPTION

Enter a description of the resource you are adding.

Usage Example

DESCRIPTION=Apache Web server

ENABLED

Oracle Clusterware uses this attribute to manage the state of the resource. Oracle Clusterware does not attempt to manage a disabled (ENABLED=0) resource either directly or because of a dependency to another resource. A disabled resource cannot be started but it can be stopped.

Oracle Clusterware does not actively monitor disabled resources, meaning that Oracle Clusterware does not check their state. However, when Oracle Clusterware starts, it does query the state of disabled resources.

Usage Example

ENABLED=1

FAILURE_INTERVAL

The interval, in seconds, during which Oracle Clusterware applies the FAILURE_THRESHOLD attribute. If the value is zero (0), then tracking of failures is disabled.

Usage Example

FAILURE_INTERVAL=30

FAILURE_THRESHOLD

The number of failures detected within a specified FAILURE_INTERVAL for a resource before Oracle Clusterware marks the resource as unavailable and no longer monitors it. If a resource fails the specified number of times, then Oracle Clusterware stops the resource. If the value is zero (0), then tracking of failures is disabled. The maximum value is 20.

Usage Example

FAILURE_THRESHOLD=3

HOSTING_MEMBERS

A space-separated, ordered list of cluster server names that can host a resource. This attribute is required only when using administrator management, and when the value of the PLACEMENT attribute is set to favored or restricted. When registering applications as Oracle Clusterware resources, use the SERVER_POOLS attribute, instead.

Note:

For resources of application type, Oracle Clusterware places servers listed in the HOSTING_MEMBERS attribute in the Generic server pool.

See Also:

"Understanding Server Pools" for more information about the Generic server pool

To obtain a list of candidate node names, run the olsnodes command to display a list of your server names.

Usage Example

HOSTING_MEMBERS=server1 server2 server3

LOAD

Oracle Clusterware interprets the value of this attribute along with that of the PLACEMENT attribute. When the value of PLACEMENT is balanced, the value of LOAD determines where best to place a resource. A nonnegative, numeric value that quantitatively represents how much server capacity an instance of a resource consumes relative to other resources. Oracle Clusterware attempts to place resources on servers with the least total load of running resources.

Usage Example

LOAD=1

NAME

A case-sensitive alphanumeric string that names the resource. Oracle recommends a naming convention that starts with an alphanumeric prefix, such as sky1, and complete the name with an identifier to describe it. A resource name can contain any platform-supported characters except the exclamation point (!) and the tilde (~). A resource name cannot begin with a period (.) nor with the string ora.

Usage Example

NAME=myApache

OFFLINE_CHECK_INTERVAL

Controls offline monitoring of a resource. The value represents the interval (in seconds) that Oracle Clusterware monitors a resource when its state is OFFLINE. Monitoring is disabled if the value is 0.

Usage Example

OFFLINE_CHECK_INTERVAL=30

PLACEMENT

Specifies how Oracle Clusterware selects a cluster server on which to start a resource. Valid values are balanced, favored, or restricted.

If you set the PLACEMENT attribute to favored or restricted, then you must also assign values to the SERVER_POOLS and HOSTING_MEMBERS attributes. If you set the value of the PLACEMENT attribute to balanced, then the HOSTING_MEMBERS attribute is not required.

See Also:

"Application Placement Policies" for more information about the PLACEMENT attribute

Usage Example

PLACEMENT=favored

RESTART_ATTEMPTS

The number of times that Oracle Clusterware attempts to restart a resource on the resource's current server before attempting to relocate it. A value of 1 indicates that Oracle Clusterware only attempts to restart the resource once on a server. A second failure causes Oracle Clusterware to attempt to relocate the resource. A value of 0 indicates that there is no attempt to restart but Oracle Clusterware always tries to fail the resource over to another server.

Usage Example

RESTART_ATTEMPTS=2

SCRIPT_TIMEOUT

The maximum time (in seconds) for an action to run. Oracle Clusterware returns an error message if the action script does not complete within the time specified. The timeout applies to all actions (start, stop, check, and clean).

Usage Example

SCRIPT_TIMEOUT=45

SERVER_POOLS

This attribute creates an affinity between a resource and one or more server pools regarding placement, and is dependent on the value of the PLACEMENT attribute.

If a resource can run on any server in a cluster, then use the default value, *, unless the resource is a cluster_resource type, in which case, the default value for the SERVER_POOLS attribute is empty. Only cluster administrators can specify * as the value for this attribute. Otherwise, you must specify in the SERVER_POOLS attribute a space-separated list of the server pools to which a particular resource can belong.

See Also:

"Understanding Server Pools" for more information about server pools and "Role-Separated Management" for more information about cluster administrators

Usage Example

SERVER_POOLS=pool1 pool2 pool3

START_DEPENDENCIES

Specifies a set of relationships that Oracle Clusterware considers when starting a resource. You can specify a space-separated list of dependencies on several resources and resource types on which a particular resource can depend.

Syntax

START_DEPENDENCIES=dependency(resource_set) [dependency(resource_set)] [...]

In the preceding syntax example the variables are defined, as follows:

See Also:

"Start Dependencies" for more details about start dependencies

START_TIMEOUT

The maximum time (in seconds) in which a start action can run. Oracle Clusterware returns an error message if the action does not complete within the time specified. If you do not specify a value for this attribute or you specify 0 seconds, then Oracle Clusterware uses the value of the SCRIPT_TIMEOUT attribute.

Usage Example

START_TIMEOUT=30

STOP_DEPENDENCIES

Specifies a set of relationships that Oracle Clusterware considers when stopping a resource.

Syntax

STOP_DEPENDENCIES=dependency(resource_set) [dependency(resource_set)] ...

In the preceding syntax example the variables are defined, as follows:

See Also:

"Stop Dependencies" for more details about stop dependencies

STOP_TIMEOUT

The maximum time (in seconds) in which a stop or clean action can run. Oracle Clusterware returns an error message if the action does not complete within the time specified. If you do not specify this attribute or if you specify 0 seconds, then Oracle Clusterware uses the value of the SCRIPT_TIMEOUT attribute.

Usage Example

STOP_TIMEOUT=30

TYPE

The type of resource indicated when you create a resource. This attribute is required when creating a resource.

Usage Example

crsctl add resource resource_name -type resource_type

See Also:

"Resource Type" for details of resource types

UPTIME_THRESHOLD

The value for UPTIME_THRESHOLD represents the length of time that a resource must be up before Oracle Clusterware considers the resource to be stable. By setting a value for the UPTIME_THRESHOLD attribute, you can indicate the stability of a resource.

Enter values for this attribute as a number followed by a letter that represents seconds (s), minutes (m), hours (h), days (d), or weeks (w). For example, a value of 7h represents an uptime threshold of seven hours.

After the time period you specify for UPTIME_THRESHOLD elapses, Oracle Clusterware resets the value for RESTART_COUNT to 0. Oracle Clusterware can alert you when the value for RESTART_COUNT reaches the value that you set for RESTART_ATTEMPTS.

Note:

Oracle Clusterware writes an alert to the clusterware alert log file when the value for RESTART_COUNT reaches the value that you set for RESTART_ATTEMPTS.

Read-Only Resource Attributes

You can view these attributes when you run the crsctl status resource command on a particular resource. Oracle Clusterware sets these attributes when you register resources.

ACTION_FAILURE_EVENT_TEMPLATE

This is an internally-managed attribute that you can view only when you run the crsctl status resource command on an ora resource. You cannot edit this attribute.

INTERNAL_STATE

An internally managed, read-only attribute that describes what, if any, action the policy engine is currently executing on the resource. Possible values and their meanings are as follows:

LAST_SERVER

For cluster_resource-type resources, this is an internally managed, read-only attribute that contains the name of the server on which the last start action for the resource succeeded.

For local_resource-type resources, this is the name of the server to which the resource instance is pinned.

LAST_STATE_CHANGE

An internally managed, read-only attribute that describes when the policy engine registers the current state of the resource. Note that this may either be the timestamp of when state of the resource changed or when the policy engine discovered the state, as occurs when crsd restarts.

PROFILE_CHANGE_EVENT_TEMPLATE

This is an internally-managed attribute that you can view only when you run the crsctl status resource command on an ora resource. You cannot edit this attribute.

RESTART_COUNT

The Oracle Clusterware daemon counts the number of attempts to restart a resource, starting from zero up to the value specified in the RESTART_ATTEMPTS attribute.

STATE

An internally managed attribute that reflects the current state of the resource as reported by Oracle Clusterware. The state of a resource can be one of the following:

STATE_CHANGE_EVENT_TEMPLATE

This is an internally-managed attribute that you can view only when you run the crsctl status resource command on an ora resource. You cannot edit this attribute.

STATE_DETAILS

An internally managed, read-only attribute that contains details about the state of a resource.

The four resource states—ONLINE, OFFLINE, UNKNOWN, and INTERMEDIATE—may map to different resource-specific values, such as mounted, unmounted, and open. Resource agent developers can use the STATE_DETAILS attribute to provide a more detailed description of this mapping, resource to the resource state.

Providing details is optional. If details are not provided, then Oracle Clusterware uses only the four possible resource states. Additionally, if the agent cannot provide these details (as may also happen to the value of the resource state), then Oracle Clusterware sets the value of this attribute to provide minimal details about why the resource is in its current state.

TARGET

An internal, read-only attribute that describes the desired state of a resource. Using the crsctl start resource_name or crsctl stop resource_name commands, however, can affect the value of this attribute.


Third-Party Applications Using the Script Agent

This section includes examples of third-party applications using script agents.

Example B-1 shows an action script that fails over the Apache Web server.

Example B-1 Apache Action Script

#!/bin/sh

HTTPDCONFLOCATION=/etc/httpd/conf/httpd.conf
WEBPAGECHECK=http://<MyVIP>:80/icons/apache_pb.gif

case $1 in
'start')
    /usr/sbin/apachectl -k start -f $HTTPDCONFLOCATION
   RET=$?
    ;;
sleep(10)
    ;;
'stop')
    /usr/sbin/apachectl -k stop
   RET=$?
    ;;
'clean')
    /usr/sbin/apachectl -k stop
   RET=$?
    ;;
'check')
    /usr/bin/wget -q --delete-after $WEBPAGECHECK
   RET=$?
    ;;
*)
   RET=0
    ;;
esac
# 0: success; 1 : error
if [ $RET -eq 0 ]; then
exit 0
else
exit 1
fi

Example B-2 shows the xclock script, which is a simple action script using xclock available as a default binary on all Linux and UNIX platforms.

Example B-2 xclock Action Script

#!/bin/bash
# start/stop/check script for xclock example
# To test this change BIN_DIR to the directory where xclock is based
# and set the DISPLAY variable to a server within your network.

BIN_DIR=/usr/X11R6/bin
LOG_DIR=/tmp
BIN_NAME=xclock
DISPLAY=yourhost.domain.com:0.0
export DISPLAY
exit_code=0

if [ ! -d $BIN_DIR ]
then
        echo "start failed"
        exit 2
fi

PID1=`ps -ef | grep $BIN_NAME | grep -v grep | grep -v xclock_app | awk '{ print $2 }'`
case $1 in
'start')
        if [ "$PID1" != "" ]
        then
           status_p1="running"
        else
           if [ -x $BIN_DIR/$BIN_NAME ]
           then
             umask 002
             ${BIN_DIR}/${BIN_NAME} & 2>${LOG_DIR}/${BIN_NAME}.log
             status_p1="started"
           else
             echo `basename $0`": $BIN_NAME: Executable not found"
             exit_code=1
           fi
        fi

         echo "$BIN_NAME: $status_p1"
         exit $exit_code
        ;;

'stop')
        if [ "${PID1}" != "" ]
        then
           kill -9 ${PID1} && echo "$BIN_NAME daemon killed"
        else
           echo "$BIN_NAME: no running Process!"
        fi
        exit $exit_code
        ;;
'check')
        if [ "$PID1" != "" ]
        then
           echo "running"
           exit 0
        else
           echo "not running"
           exit 1
        fi
        ;;*)
        echo "Usage: "`basename $0`" {start|stop|check}"
        ;;
esac

Example B-3 shows an example of a shell script for an agent to monitor a file. When the agent is started, it creates the file (which is specified through an attribute) and when it is stopped, it deletes the file. The CHECK action consists of merely checking if the file exists or not. The variables with the _CRS_ prefix are attribute values that are provided to the script in its environment.

Example B-3 Action Script Example

#!/bin/sh
TOUCH=/bin/touch
RM=/bin/rm
PATH_NAME=/tmp/$_CRS_NAME

#
# These messages go into the CRSD agent log file.
echo " *******   `date` ********** "
echo "Action script '$_CRS_ACTION_SCRIPT' for resource[$_CRS_NAME] called for action $1"
#

case "$1" in
  'start')
     echo "START entry point has been called.."
     echo "Creating the file: $PATH_NAME"
     $TOUCH $PATH_NAME
     exit 0
     ;;

  'stop')
     echo "STOP entry point has been called.." 
     echo "Deleting the file: $PATH_NAME"
     $RM $PATH_NAME
     exit 0
     ;;

  'check')
    echo "CHECK entry point has been called.."
    if [ -e $PATH_NAME ]; then
        echo "Check -- SUCCESS"
        exit 0
    else
        echo "Check -- FAILED"
        exit 1
    fi
    ;;

  'clean')
     echo "CLEAN entry point has been called.."
     echo "Deleting the file: $PATH_NAME"
     $RM -f $PATH_NAME
     exit 0
     ;;

esac