NetApp IGroup Config Mismatches Test

Initiator groups (igroups) are tables of host identifiers (FCP, WWPNs, or iSCSI node names) that are used to control hosts' access to LUNs.

igroups specify which initiators have access to which LUNs. igroups can be created either before or after LUNs are created, but they must be created before a LUN is mapped to an igroup. Initiator groups can have multiple initiators, and multiple igroups can have the same initiator. However, a LUN can not be mapped to multiple igroups that have the same initiator.

An initiator cannot be a member of igroups of differing ostypes.

This test reveals if any mismatch of the cluster failover setting has occurred between the local and partner systems of a cluster and also the following:

  • How many initiator groups have an incompatible operating system?
  • How many initiator groups are with an invalid use partner setting?
  • How many initiator groups have an operating system that is incompatible with the use partner setting and the VSA setting?
  • How many initiator groups have the ALUA setting mismatch between the local and partner systems?

Target of the test : A NetApp Unified Storage

Agent deploying the test : An external/remote agent

Outputs of the test : One set of results for the NetApp storage system being monitored.

Configurable parameters for the test
Parameters Description

Test Period

How often should the test be executed.

Host

The host for which the test is to be configured.

Port

Specify the port at which the specified host listens in the Port text box. By default, this is NULL.

User

Here, specify the name of the user who possesses the following privileges:

login-http-admin,api-aggr-check-spare-low,api-aggr-list-info,api-aggr-mediascrub-list-info,api-aggr-scrub-list-info,api-cifs-status,api-clone-list-status,api-disk-list-info,api-fcp-adapter-list-info,api-fcp-adapter-stats-list-info,api-fcp-service-status,api-file-get-file-info,api-file-read-file,api-iscsi-connection-list-info,api-iscsi-initiator-list-info,api-iscsi-service-status,api-iscsi-session-list-info,api-iscsi-stats-list-info,api-lun-config-check-alua-conflicts-info,api-lun-config-check-cfmode-info,api-lun-config-check-info,api-lun-config-check-single-image-info,api-lun-list-info,api-nfs-status,api-perf-object-get-instances-iter*,api-perf-object-instance-list-info,api-quota-report-iter*,api-snapshot-list-info,api-vfiler-list-info,api-volume-list-info-iter*.

If such a user does not pre-exist, then, you can create a special user for this purpose using the steps detailed in Creating a New User with the Privileges Required for Monitoring the NetApp Unified Storage.

Password

Specify the password that corresponds to the above-mentioned User.

Confirm Password

Confirm the Password by retyping it here.

Authentication Mechanism

In order to collect metrics from the NetApp Unified Storage system, the eG agent connects to the ONTAP management APIs over HTTP or HTTPS. By default, this connection is authenticated using the LOGIN_PASSWORD authentication mechanism. This is why, LOGIN_PASSWORD is displayed as the default authentication mechanism.

Use SSL

Set the Use SSL flag to Yes, if SSL (Secured Socket Layer) is to be used to connect to the NetApp Unified Storage System, and No if it is not.

API Port

By default, in most environments, NetApp Unified Storage system listens on port 80 (if not SSL-enabled) or on port 443 (if SSL-enabled) only. This implies that while monitoring the NetApp Unified Storage system, the eG agent, by default, connects to port 80 or 443, depending upon the SSL-enabled status of the NetApp Unified Storage system - i.e., if the NetApp Unified Storage system is not SSL-enabled (i.e., if the Use SSL flag above is set to No), then the eG agent connects to the NetApp Unified Storage system using port 80 by default, and if the NetApp Unified Storage system is SSL-enabled (i.e., if the Use SSL flag is set to Yes), then the agent-NetApp Unified Storage system communication occurs via port 443 by default. Accordingly, the API Port parameter is set to default by default.

In some environments however, the default ports 80 or 443 might not apply. In such a case, against the API Port parameter, you can specify the exact port at which the NetApp Unified Storage system in your environment listens, so that the eG agent communicates with that port for collecting metrics from the NetApp Unified Storage system.

vFilerName

A vFiler is a virtual storage system you create using MultiStore, which enables you to partition the storage and network resources of a single storage system so that it appears as multiple storage systems on the network. If the NetApp Unified Storage system is partitioned to accommodate a set of vFilers, specify the name of the vFiler that you wish to monitor in the vFilerName text box. In some environments, the NetApp Unified Storage system may not be partitioned at all. In such a case, the NetApp Unified Storage system is monitored as a single vFiler and hence the default value of none is displayed in this text box.

Timeout

Specify the duration (in seconds) beyond which the test will timeout if no response is received from the device. The default is 120 seconds.

DD Frequency

Refers to the frequency with which detailed diagnosis measures are to be generated for this test. The default is 1:1. This indicates that, by default, detailed measures will be generated every time this test runs, and also every time the test detects a problem. You can modify this frequency, if you so desire. Also, if you intend to disable the detailed diagnosis capability for this test, you can do so by specifying none against DD frequency.

Detailed Diagnosis

To make diagnosis more efficient and accurate, the eG Enterprise suite embeds an optional detailed diagnostic capability. With this capability, the eG agents can be configured to run detailed, more elaborate tests as and when specific problems are detected. To enable the detailed diagnosis capability of this test for a particular server, choose the On option. To disable the capability, click on the Off option.

The option to selectively enable/disable the detailed diagnosis capability will be available only if the following conditions are fulfilled:

  • The eG manager license should allow the detailed diagnosis capability
  • Both the normal and abnormal frequencies configured for the detailed diagnosis measures should not be 0.
Measurements made by the test
Measurement Description Measurement Unit Interpretation

Is CF mode mismatched?

Indicates whether/not the cluster failover setting of the local system is different from that of the partner system.

 

In a cluster setup of the storage systems, the Cluster failover modes of the systems in that cluster need to match so that the cluster failover would function appropriately. This measure reports the value Yes if the cluster failover setting is different in the local system and the partner system and the value No if the settings are same in both the local system and the partner system.

The values reported by this measure and their numeric equivalents are available in the table below:

Measure Value Numeric Value
No 0
Yes 1

Note:

This measure reports the Measure Values listed in the table above to indicate whether/not the CF mode is mistmatched. However, in the graph of this measure, the same is indicated using only the Numeric Values listed in the above table.

The Detailed Diagnosis of this measure shows the mismatching local and partner Cluster Failover modes.

Igroups with invalid OS type

Indicates the number of initiator groups whose Operating system is not compatible with that of the configured fcp cfmode.

Number

Some host operating systems are compatible with certain selective fcp cfmodes only. In such a scenario, the OS type of the initiator group must match the fcp cfmode for proper functioning of the intiator group.

The detailed diagnosis of this measure indicates the name of the initiator group and the OS type of the initiator group.

Igroups with invalid use-partner setting

Indicates the number of initiator groups with an invalid use-partner setting - i.e., the use partner setting of the initiator group is not compatible with that of the configured fcp cfmode.

Number

The use-partner setting indicates whether the initiators in the initiator group are allowed to use the partner's port ina cluster setup. Initiator groups with an invalid use-partner setting can result in some hosts losing LUNs during takeover.

The detailed diagnosis of this measure indicates the name of the affected initiator group and the use partner setting of that corresponding initiator group.

Igroups with mismatching use-partner OS type setting

Indicates the number of initiator groups whose use partner setting is not compatible with their configured operating system.

Number

In a cluster setup, in order to ensure proper behavior of the Storage systems during failover, the host operating systems are designed to support only certain use parameter settings. A difference in the use parameter setting may result in performance bottleneck.

The detailed diagnosis of this measure highlights this incompatibility issue by listing out the initiator group, OS type and the use parameter setting of that initiator group.

Igroups with invalid ALUA setting

Indicates the number of initiator groups for which the ALUA setting do not match between the local and the partner unified storage systems.

Number

ALUA is a T10 standard that specifies the access characteristics (in terms of performance and supported SCSI commands) of a Logical Unit that can be accessed through more than one target port. ALUA is typically used by host multi-path software to recognize primary and secondary paths to a Logical Unit when more than one path are available to the Logical Unit. If the ALUA setting does not match between the local and partner filers, it would affect the host multi-path software's ability to distinguish between the primary and secondary paths, which could lead to the poor performance of the system.

The detailed diagnosis of this measure provides the name of the affected initiator group and the status of the ALUA (whether enabled or disabled) in the local and partner storage systems.

Igroups with invalid VSA setting

Indicates the number of initiator groups with the VSA setting that do not match with that of the configured operating system.

Number

The Volume Set Addressing (VSA) setting is enabled only for the initiator groups that are configured with the HPUX operating system. Incorrect settings of the VSA may deny hosts access to some/all LUNs.

The detailed diagnosis of this measure indicates the name of the initiator group, the operating system of the initiator groups and the status (whether enabled/disabled) of the VSA setting.