Adding (Cascading) a J4500 Array to An Existing Zoned J4500 Array

The example in the following section describes how to add array storage to an existing configured array. There are three sets of steps required to cascade (or add) a J4500 array to an existing J4500 array using the CAM browser interface:

• To Prepare an Existing Array Prior to Cascading Additional Storage

• To Prepare a New J4500 Array for Cascading

• To Cascade Arrays Using CAM

To Prepare an Existing Array Prior to Cascading Additional Storage

Before You Begin

This procedure takes you through the steps required to temporarily disable the Access Configuration state for an existing array, in preparation for cascading an additional array. These instructions assume that CAM is currently used to manage existing array storage.

1. Verify a backup of any existing data is made.

   This is a precautionary step and therefore a best practice.

2. Log into the CAM management host by opening the browser and entering the following address:

   https://host-name:6789

   Where host-name is the DNS name of the server connected to the array.

3. In the left navigation pane, expand the tree for the connected server host and click Access Configuration for the first SAS Domain which is represented by the domain's SAS address number. See Example SAS Domain Access Configuration Summary Page.
   

   Figure 3-3 Example SAS Domain Access Configuration Summary Page

   
4. Click Configure.

   The Configure Access Between Initiators and Disks page displays. See Example Initiator to Disk Access Configuration Page.

   
   

   Figure 3-4 Example Initiator to Disk Access Configuration Page

   
5. Write down the initiator SAS address and associated drives for the SAS domain, and then perform an Export operation to save a copy of the existing initiator-to-disk access configurations.
6. In the left navigation pane, click the Administration page for the domain.

   The Administration page displays.

   
   

   Figure 3-5 Example SAS Domain Administration Page

   
7. Change the access configuration state for the SAS domain to Disabled (see Example SAS Domain Administration Page)
8. Click Save.
9. Repeat Steps 3 though 8 for the second SAS domain.

   Be sure to perform an Export operation to save a copy of the existing initiator-to-disk access configurations since you might need them later.

10. Un-register the array in CAM.
    1. From the left navigation pane, select Storage Systems.

       The Storage System Summary page displays.

    2. Select the checkbox to the left of the array.

       This enables the Remove button.

    3. Click Remove.

    The array is unregistered and removed from the Storage System Summary. The Proxy hosts connected to the un-registered array will automatically be removed as well.

11. Disconnect the array from the server, and disconnect AC power to the array.

To Prepare a New J4500 Array for Cascading

Before You Begin

Before cascading can occur, all arrays that will be cascaded together either using new out-of-the-box arrays, or an array that is being added to an existing array setup, must be prepared using the steps in this procedure.

1. Connect a server host running a full version of CAM (6.4.1 at a minimum) to both SAS fabrics of the new array (with a connection to the J4500 array SAS A and a connection to SAS B). See New Array Being Prepared for Cascading. This host will be the primary host.

   The array must not be cascaded to any other J4500 array at this time. This procedure is performed on one array at a time.

   
   

   Figure 3-6 New Array Being Prepared for Cascading

   
2. Power on the array by connecting AC power.
3. After one minute, power on the primary host, if not already powered on.
4. Log into CAM on the primary host by opening the browser and entering the following address:

   https://host-name:6789

   Where host-name is the DNS name of the server connected to the array.

5. From the Storage System Summary page, click Register and follow the wizard to register the new array using the host name or host IP address of the host in the Registration window.
6. In the left navigation pane, expand the tree for the connected server host and click Access Configuration for the first SAS Domain which is represented by the domain's SAS address number. See Example Access Configuration Summary for SAS Domain Selected in CAM.
   

   Figure 3-7 Example Access Configuration Summary for SAS Domain Selected in CAM

   

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   Caution - Be sure that you have selected the appropriate array before going to the next step. The Reset to Default procedure clears any existing zoning configurations. If there are pre-existing zoning configurations, they can be reset to defaults by CAM if you know the SAS domain passwords. If you do not know the SAS domain passwords, you must clear the enclosure zoning passwords as described in Chapter 5, Troubleshooting.

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7. Click Reset to Default.

   This action clears any previous access configurations for the SAS domain of the array.

8. Read the pop-up warning message and then click OK.
9. From the Access Configuration Summary page for the SAS domain which you just reset to defaults, click Configure.

   The Configure Access Between Initiators and Disks page displays. See Example Configure Access Between Initiators and Disks in SAS Domain Page.

   
   

   Figure 3-8 Example Configure Access Between Initiators and Disks in SAS Domain Page

   
10. Clear old initiator-to-disk access lists, if any, by selecting those entries in the Initiator Centric Access List and clicking Remove.
11. Click Save.

    This clears any old initiator to disk access configurations in the domain.

12. Repeat Steps 6 through 11 for the second SAS domain of the array.

    When done, all of the storage in this array will be accessible in both of the SAS domains: the initiator connected to array SAS A will see all of the disks, and the initiator connected to array SAS B will also see all of the disks.

13. Un-register the array in CAM.
    1. From the left navigation pane, select Storage Systems.

       The Storage System Summary page displays.

    2. Select the checkbox to the left of the array.

       This enables the Remove button.

    3. Click Remove.
14. Disconnect the array from the server, and disconnect AC power to the array.

To Cascade Arrays Using CAM

Before You Begin

Before cascading arrays, make a note of the following and take actions as required:

• Existing arrays with CAM access configurations that you want to save should have been prepared as described in To Prepare an Existing Array Prior to Cascading Additional Storage.

• New arrays being cascaded together, or added to an existing array, should have been prepared as described in To Prepare a New J4500 Array for Cascading.

• If any initiators (HBA connections) from any attached hosts are not seen in CAM during the following process, verify that operating system multipathing software is disabled on those hosts. In addition, a reboot might be necessary to force an attached host to register their initiators with the storage arrays.

1. Disconnect all attached hosts to the existing array setup. Then, cable the existing and new arrays to the first (primary) host as shown in Temporary Cascade Configuration.

   The primary host should have an initiator connection to array SAS fabric A and an initiator connection to SAS fabric B. Array 1 is either an existing or a new storage array. Array 2 is a new array which is attached to the primary host.

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   Note - This cascade configuration differs from the supported configuration that will be used during normal operation. This configuration is temporary but required in order to synchronize certain settings between the existing array and the new array that is being added.

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   Figure 3-9 Temporary Cascade Configuration

   
2. Power on the cascaded arrays by reconnecting AC power.

   The new arrays might take a few minutes for all drives to be recognized by the server's initiators.

3. After one minute, power on the primary host, if not already powered on.
4. Log into CAM on the primary host by opening the browser and entering the following address:

   https://host-name:6789

   Where host-name is the DNS name of the server connected to the array.

5. From the Storage System Summary page, click Register and follow the wizard to register the cascaded arrays using the host name or host IP address of the primary host in the Registration window.

   All attached arrays should be found. If they are not, perform a host reboot (i.e. Full reboot reconfigure on Solaris) and attempt the registration again.

6. In the left navigation pane, expand the tree for the connected server host and click Administration for the first SAS Domain which is represented by the domain's SAS address number.

   The Administration page displays. See Example SAS Domain Administration Page.

   
   

   Figure 3-10 Example SAS Domain Administration Page

   
7. Click Enable for the first SAS domain found underneath the entry for your primary host.
8. Click the Change Password checkbox.
9. Select the “Change Password in the Array Registration Database” option (see Example SAS Domain Administration Page), enter your desired (or existing) password, and click Save.
10. From the Administration page for the domain, click Disable.
11. Repeat Steps 6 through 10 for each SAS domain under the primary host.

    This will synchronize your password information so that it is the same for both SAS domains and for both J4500 arrays.

12. Attach the second host and change the cabling from the primary (first) host to conform to a supported cascaded array configuration (refer toMultipathing Configuration Guidelines). An example for a two host configuration is shown in Supported Cascade Cabling for a Two-Host Configuration.

    Due to the large number of disks, it may take a few minutes to discover all of the arrays and initiators.

    When you have completed this step, all the arrays in the cascade should be discovered and the access configuration for all SAS domains will be in the “disabled” state.

    
    

    Figure 3-11 Supported Cascade Cabling for a Two-Host Configuration

    

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    Caution - Do not discover your proxy hosts at this time. When SATA drives are in use, all Access Configuration changes must be done from the primary host, including the Access Configuration for secondary host initiators. Do not run any I/O, commands (i.e., format) or software on any hosts other than the primary CAM host. All configuration must be done from the primary host.

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13. In the left navigation pane, expand the tree for the connected server host and click Access Configuration for the first SAS Domain which is represented by the domain's SAS address number.

    The Access Configuration Summary page displays. See Access Configuration Summary Page.

    
    

    Figure 3-12 Access Configuration Summary Page

    
14. Click Configure.

    The Configure Access Between Initiators and Disks page displays. See Example Configure Access Between Initiators and Disks Page.

    At this time, all arrays, domains, and initiators from all attached hosts should be seen within the corresponding Access Configuration Pages.

    If any initiators from any attached hosts are not seen, verify that the OS multipathing software is disabled on those hosts. In addition, a reboot might be necessary to force an attached host to register their initiators with the storage arrays.

    
    

    Figure 3-13 Example Configure Access Between Initiators and Disks Page

    
15. At the Configure Access Between Initiators and Disks page, configure initiator-to-disk relationships for an initiator as follows:
    1. Select an initiator and then select the disks to be given access to that initiator.

       • If the initiator selected is from a host whose cable did not need to be moved from one array port to another in order to conform to a supported array cascade configuration, you can implement an existing access configuration for it. Any host connections that were moved from their original array port connection to a different array port must have access configuration manually recreated for that initiator.

       • If multipathing is planned, drives may be shared by the initiators of a single host. The initiators must be attached to separate SAS domains to ensure a separate failover path. Disk drives in the array should never be shared by more than one host whether multipathing or not.

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         Note - The J4500 array is not supported in a clustering configuration.

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    2. Click Add/Modify to store the configuration to the Initiator Centric Access List.
    3. Verify the Access Configuration state is set to “Enable”.
    4. Click Save.
    5. Repeat Steps A through D for each initiator.

       All initiators connected to the domain should be configured at this time (i.e., initiator #1 might have all odd numbered disks and initiator #2 might have all even numbered disks). This includes the initiators of other attached hosts.

16. Repeat Steps 13 through 15 to configure other initiator-to-disk relationships for the other SAS domains found under the entry for the primary host.

    If multiple initiators are seen, access configuration should also be performed at this time. This includes the initiators of other attached hosts.

17. Configure operating system multipath software for each attached host (refer to Chapter 4, SAS Multipathing).

    This is only required in a situation where two initiators of a host were configured in CAM to share the same drives in different SAS domains. Operating system multipath drivers are used to control path failover.