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Reference for Oracle Solaris Cluster 4.4

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Updated: August 2018
 
 

scha_cluster_get_zone (3HA)

Name

scha_cluster_open, scha_cluster_open_zone, scha_cluster_get, scha_cluster_get_zone, scha_cluster_close - access and obtain information about a cluster

Synopsis

cc [flags…] –I /usr/cluster/include file –L /usr/cluster/lib 
–l scha#include <scha.h>scha_err_t scha_cluster_open(
     scha_cluster_t *handle);
scha_err_t scha_cluster_open_zone(const char *cluster, 
     scha_cluster_t *handlep);
scha_err_t scha_cluster_get(scha_cluster_t handle, const char **
     tag, ...);
scha_err_t scha_cluster_get_zone(const char *cluster, 
     scha_cluster_t handlep, const char *cluster_tag, ...);
scha_err_t scha_cluster_close(scha_cluster_t handle);

Description

The scha_cluster_open(), scha_cluster_get(), and scha_cluster_close() functions are used together to obtain information about a cluster.

scha_cluster_open() initializes cluster access and returns an access handle to be used by scha_cluster_get(). The handle argument is the address of a variable to hold the value that is returned by the function call.

scha_cluster_get() accesses cluster information as indicated by the tag argument. The handle argument is a value that is returned from a prior call to scha_cluster_open(). The tag argument is a string value that is defined by a macro in the scha_tags.h header file. The arguments that follow the tag depend on the value of the tag argument.

You might need to provide an additional argument after the tag argument to indicate a cluster node from which the information is to be retrieved. The last argument in the argument list is to be of a type that is suitable to hold the information that is indicated by the tag argument. This argument is the output argument for the cluster information. No value is returned for the output argument if the function fails. Memory that is allocated to hold information that is returned by the scha_cluster_get() function remains intact until scha_cluster_close() is called on the handle that is used for the scha_cluster_get() function.

scha_cluster_close() takes a handle argument that is returned from a previous call to the scha_cluster_get() function. This function invalidates the handle and frees memory that is allocated to return values to scha_cluster_get() calls that were made with the handle. Note that memory, if needed to return a value, is allocated for each get call. Space allocated to return a value in one call is not overwritten and reused by subsequent calls.

The scha_cluster_open_zone() and scha_cluster_get_zone() functions serve the same purpose as scha_cluster_open() and scha_cluster_get() respectively, with an additional cluster argument specifying the name of a zone cluster in which the resource groups exist and on which you want to operate. These functions are useful when code is executed in the global zone but needs to operate on a specified zone cluster. They cannot be used within a zone cluster to access a different zone cluster.

If the cluster argument to scha_cluster_open_zone() or scha_cluster_get_zone() is NULL, the query is performed on the cluster within which the call is executed; in other words, the call with NULL argument is equivalent to scha_cluster_open() or scha_cluster_get(), respectively.

To close the handle returned by scha_cluster_open_zone(), use scha_cluster_close(). No cluster argument is required.

Macros That You Can Use for tag Arguments

Macros that are defined in scha_tags.h that you can use as tag arguments follow. The type of the output argument and any additional arguments are indicated. Structure and enum types are described in scha_calls(3HA).

SCHA_ALL_LOADLIMITS

The output argument type is scha_str_array_t**.

This macro returns all the loadlimit names defined in the cluster.

SCHA_ALL_NODEIDS

The output argument type is scha_uint_array_t**.

This macro returns numeric node identifiers of all the nodes in the cluster.

SCHA_ALL_NODENAMES

The output argument type is scha_str_array_t**.

This macro returns the names of all nodes in the cluster.

SCHA_ALL_PRIVATELINK_HOSTNAMES

The output argument type is scha_str_array_t**.

This macro returns the host names for all cluster nodes by which the nodes are addressed on the cluster interconnect.

SCHA_ALL_PSTRINGS

The output argument type is scha_str_array_t**.

This macro returns the names of all private strings that are defined in the cluster. For more information about private strings, see the clpstring(8CL) man page.

SCHA_ALL_RESOURCEGROUPS

The output argument type is scha_str_array_t**.

This macro returns the names of all the resource groups that are being managed on the cluster.

SCHA_ALL_RESOURCETYPES

The output argument type is scha_str_array_t**.

This macro returns the names of all the resource types that are registered on the cluster.

SCHA_CLUSTERNAME

The output argument is type char**.

This macro returns the name of the cluster.

SCHA_HARD_LOADLIMIT

The output argument type is scha_str_array_t**.

This macro returns the hard load limit values for all nodes in the cluster, for a specified limit name. It requires an additional argument of the type char * that is a load limit name string.

Each element of the string array output is of the format "%s=%d", where the left-side string is a nodename, and the right-side integer is the hard load limit value for the specified limit name on that node. If no hard limit is specified, the value of -1 is displayed for the hard limit.

SCHA_LOADLIMIT_PROPS

The output argument type is scha_str_array_t**.

This macro returns the hard and soft load limit values (delimited by /) for all nodes in the cluster, for a specified limit name. It requires an additional argument of the type char * that is a load limit name string.

Each element of the string array output is a string of the format "%s=%d/%d", where the left-side string is a nodename, the first integer is the soft limit, and the second integer is the hard limit. If no hard limit is specified, the value of -1 is displayed for the hard limit. If no soft limit is specified, the value 0 is displayed for the soft limit.

SCHA_LOADLIMITS_NODE

The output argument type is scha_str_array_t**.

This macro returns the load limits (delimited by /) and limit names for a specific node. It requires an additional argument of the type char * that is a nodename.

Each element of the string array output is a string of the format "%s=%d/%d", where the string is a limit name defined on the specified node, the first, integer is the soft limit value, and the second integer is the hard limit value. If no hard limit is specified, the value of -1 is displayed for the hard limit. If no soft limit is specified, the value 0 is displayed for the soft limit.

SCHA_NODEID_LOCAL

The output argument type is uint_t*.

This macro returns the numeric node identifier for the node where the command is executed.

SCHA_NODEID_NODENAME

The output argument type is uint_t*. An additional argument is of type char *. The macro requires an additional argument that is a name of a cluster node.

This macro returns the numeric node identifier of the node indicated by the name.

SCHA_NODENAME_LOCAL

The output argument type is char**.

This macro returns the name of the cluster node where the function is executed.

SCHA_NODENAME_NODEID

The output argument type is char**. An additional argument is of type uint_t. The additional argument is a numeric cluster node identifier.

This macro returns the name of the node indicated by the numeric identifier.

SCHA_NODESTATE_LOCAL

The output argument type is scha_node_state_t*.

This macro returns SCHA_NODE_UP or SCHA_NODE_DOWN, depending on the state of the node where the command is executed.

SCHA_NODESTATE_NODE

The output argument type is scha_node_state_t*. An additional argument is type char*. The macro requires an additional unflagged argument that is the name of a cluster node.

This macro returns SCHA_NODE_UP or SCHA_NODE_DOWN, depending on the state of the named node.

SCHA_PRIVATELINK_HOSTNAME_LOCAL

The output argument type is char**.

This macro returns the host name by which the node on which the command is run is addressed on the cluster interconnect.

SCHA_PRIVATELINK_HOSTNAME_NODE

The output argument type is char**. An additional argument is of type char *. This macro requires an additional unflagged argument that is the name of a cluster node.

This macro returns the host name by which the named node is addressed on the cluster interconnect.

SCHA_PSTRING

The output argument type is char**.

This macro returns the clear text value of a private string. It requires an additional argument of type char* that provides the name of a private string. Users other than the root user require solaris.cluster.modify authorization to use this query tag. For more information about private strings, see the clpstring(8CL) man page.

SCHA_RESOURCE_SECURITY

The output argument type is char**.

This macro returns the current setting of the resource_security cluster property.

SCHA_RG_FAILOVER_LOG

The output argument type is scha_str_array_t**. An additional argument is of type uint_t. The additional argument is an integer between 1 and 7 inclusive, indicating the number of days of failover history to retrieve.

This macro returns a log of resource-group switchover and failover events. Each string in the string array contains the following semicolon-separated fields:

resource-group-name;source-nodes;target-nodes;time-stamp
  • The source-nodes field is a comma-separated list of those nodes from which the resource group failed over or was switched manually. A source-nodes field that is empty indicates an event where the resource group was switched online manually or during a cluster boot-up.

  • The target-nodes field is a comma-separated list of those nodes to which the resource group failed over or was switched manually. A target-nodes field that is empty indicates that the resource group went offline.

  • The time-stamp value is written in ctime format. For an example of the output format, see the scha_cluster_get(8HA) man page. For more information about the ctime() function, see the ctime(3C) man page.

SCHA_SOFT_LOADLIMIT

The output argument type is scha_str_array_t**.

This macro returns the soft load limits for all nodes in the cluster, for a specified limit name. It requires an additional argument of the type char * that is a load limit name string.

Each element of the string array output is of the format "%s=%d", where the left-side string is a nodename, and the right-side integer is the soft load limit value for the specified limit name on that node. If no soft limit is specified, the value 0 is displayed for the soft limit.

SCHA_SYSLOG_FACILITY

The output argument type is int*.

This macro returns the number of the syslog(3C) facility that the RGM uses for log messages. The value that is returned is 24, which corresponds to the LOG_DAEMON facility value.

Errors

SCHA_ERR_NOERR

The function succeeded.

See scha_calls(3HA) for a description of other error codes.

Examples

Example 1 Using the scha_cluster_get() Function

The following example uses the scha_cluster_get() function to get the names of all cluster nodes. The function also determines whether the node is up or down.

The code example also prints the soft and hard load limit settings that are configured for the limitname called mylimit for every cluster node where that limit was configured. The load limit values for each node are printed in the format: nodename=softlimit/[ hardlimit], where the hardlimit value is unlimited (-1) if there is no hard limit set.

#include <scha.h>
#include <stdio.h>
#include <stdlib.h>

main()
{
        scha_err_t              err;
        scha_node_state_t       node_state;
        scha_str_array_t        *all_nodenames;
        scha_cluster_t          handle;
        int                     ix;
        const char              *str;
        scha_str_array_t        *load_limits;

        err = scha_cluster_open(&handle);
        if (err != SCHA_ERR_NOERR) {
                fprintf(stderr, "FAILED: scha_cluster_open()0);
                exit(err);
        }

        err = scha_cluster_get(handle, SCHA_ALL_NODENAMES, &all_nodenames);
        if (err != SCHA_ERR_NOERR) {
                fprintf(stderr, "FAILED: scha_cluster_get()0);
                exit(err);
        }

        for (ix = 0; ix < all_nodenames->array_cnt; ix++) {
                err = scha_cluster_get(handle, SCHA_NODESTATE_NODE,
                    all_nodenames->str_array[ix], &node_state);
                if (err != SCHA_ERR_NOERR) {
                        fprintf(stderr, "FAILED: scha_cluster_get()"
                            "SCHA_NODESTATE_NODE0);
                        exit(err);
                }

                switch (node_state) {
                case SCHA_NODE_UP:
                        str = "UP";
                        break;
                case SCHA_NODE_DOWN:
                        str = "DOWN";
                        break;
                }

                printf("State of node: %s value: %s\n",
                    all_nodenames->str_array[ix], str);
        }
        err = scha_cluster_get(handle, SCHA_LOADLIMIT_PROPS, "mylimit",
            &load_limits);

        printf("\n\nLoad limits settings for limitname 'mylimit':\n\n");

        for (ix = 0; ix < load_limits->array_cnt; ix++) {
            printf("%s\n", load_limits->str_array[ix]);
        }
}

Files

/usr/cluster/include/scha.h

Include file

/usr/cluster/lib/libscha.so

Library

Attributes

See attributes(7) for descriptions of the following attributes:

ATTRIBUTE TYPE
ATTRIBUTE VALUE
Availability
ha-cluster/developer/api
Interface Stability
Evolving

See Also

syslog(3C), scha_calls(3HA), scha_cluster_getlogfacility(3HA), scha_cluster_getnodename(3HA), scha_strerror(3HA), attributes(7), rg_properties(7), scha_cluster_get(8HA)