A loader (also called tape library or autoloader) is a device that consists of drive(s), a magazine with slots for tape cartridges and a robotic mechanism that moves media between the slots and drives. In SEP sesam there is no dependency to use specific manufacturers' devices or device types; you can check the list of supported hardware at Supported Storage Hardware.
SEP sesam can detect and automatically configure storage hardware in your environment if the hardware is supported and recognized by the operating system (it must be listed in the OS device manager), where the SEP sesam Server or Remote Device Server is installed.
During SEP sesam Server installation, SEP sesam checks the SCSI API of the operating system for connected storage devices and puts accessible device files (SCSI address) into the SEP sesam database. This auto-detection works for most devices, but for certain types of loaders the connection between loader and drives cannot be recognized automatically. You have to manually verify and configure such devices. You also have to manually configure any backup device that is connected after SEP sesam installation. Note that the procedure differs depending on your operating system (Linux or Windows).
Automatically detected storage devices
SEP sesam displays automatically detected backup devices in GUI: Main selection -> Components -> Loaders. All detected loaders are displayed; you only need to select a loader to review its properties, and then click OK to confirm the loader configuration.
|It is recommended that SEP sesam auto-configures backup devices, but even for the automatically configured backup devices you should enable persistent naming and check their configuration to configure them as required and avoid errors in SEP sesam operation. See sections Enabling persistent naming for tape devices and Using slu topology for detecting devices.|
Preparing loaders and drives
Preparation of storage devices is based on the following general sequence. Note that this sequence might differ for specific devices and might require some additional steps.
- Connect a storage device to SEP sesam Server or SEP sesam Remote Device Server (RDS). Follow the configuration instructions specified by the device vendor or the operating system.
- Install the latest vendor driver for the tape drives, and also the latest driver for the loader. Note that during SEP sesam Server installation SEP sesam will check the SCSI API of the operating system for connected storage devices and enter working device files (SCSI address) into SEP sesam database automatically. Typically, this auto-detection will work for most devices, but there are some exceptions that need manual verification and configuration of the server operating system to allow device discovery.
- Restart the system to ensure that connected storage devices become known to the system.
- Check your device vendor documentation for any additional steps that may have to be performed.
Manually configuring loaders and drives
Checking hardware configuration on Windows
If your loader is detected by SEP sesam automatically, you can skip this step. If you have to add it manually to your Windows system, you must ensure that the hardware is recognized correctly by the operating system in the Windows Device Manager.
- Open Windows Device Manager and check that the selected hardware is present and recognized, as shown in the example below.
- In the Device Manager window, also check that the tape drives have a Tape Symbolic Name displayed.
If it is not recognized, it will be shown with a status Unknown Medium Changer as in the following example.
If it is shown as unknown, right-click it and select Update Driver Software to open the Update Driver Software-Unknown Medium Changer window. Then select or download and install the appropriate driver.
|A wrong driver (or no driver at all) is a common cause of errors. Identify the hardware manufacturer and download the correct driver from their support website to ensure proper configuration of your hardware device. For more information, check the documentation provided by the hardware manufacturer.|
Enabling persistent naming for tape devices
Using slu topology for detecting devices
(Re-)Configuring loaders and drives in SEP sesam GUI
These steps differ slightly if you are manually configuring a new device or re-configuring an already existing device. If you are re-configuring an existing device, select it from the list of Loaders and double-click to open the properties and review them, as described in the following steps. Then proceed with re-configuration of drives.
Manually configuring a new loader
- If you are configuring a new device, in SEP sesam GUI from the Main selection select Components then Loaders. Click New Loader.
- In the New Loader window, enter its properties which you can read from the output of: <SESAM_BIN>/sesam/slu topology
Check the output to see if the devices are used correctly by SEP sesam and detect the available SCSI addresses. For details, see above section Using slu topology for detecting devices.
- Device name: SCSI device filename of the loader. In our Windows example, this is Changer0. On Linux systems it would be, for example, /dev/sg2.
- Device server: SEP sesam Server or Remote Device Server (RDS) to which the loader is connected. In small environments, the loader or disk array is usually installed directly on the SEP sesam Server. More complex backup environments use RDS instead.
- Type: The device type, e.g., LTO4.
- Ctrl : Make sure that DIR_SLU is selected. This is applicable for all loaders which are connected by SAS/iSCSI/FC to the SEP sesam Server or RDS, and provide a robotic control of tape media. (Other options are DIR_VIRT which defines a virtual loader, DIR_DISK which enables controlling a pool of several hard disks, and DIR_ACSLS which defines an ACSLS loader.)
- Slots: Number of slots in the loader.
- Ports: Number of mail slots in the loader.
- Barcode: Depending on whether the loader has a barcode reader or not, select yes or no.
- Auto unload function: Almost all autoloaders and tape libraries allow explicit commands to transport tapes to and from the loader mechanism. It is strongly recommended to disable Auto unload function by setting it to No and allow the manufacturer's drive settings to perform as designed.
Example of a configured loader
Creating or re-configuring drives
- From the Components, select Drives. In SEP sesam, every drive has to be a member of a drive group. If you have not yet created a drive group, you have to create it now: click the New Drive Group button and enter the name of the new drive group, e.g., Tape_Drives.
- Select the drive group for which you want to (re-)configure the drives, e.g., Tape Drives, and create new drives by clicking New Drive or select existing drives for which you enforced the persistent naming and you have to reconfigure.
- In the New Drive window/Drive properties, the following fields are available:
- Drive number: Number is automatically assigned by SEP sesam; you can change it if you are creating a new drive.
- Drive name: Optionally, enter a description, e.g., logical identifier of a drive.
- Drive type: Select the drive type from the drop-down list of existing drives (LTO, DLT, SLR, etc.)
- Loader: If the drive belongs to the loader, select 1. If it is a single tape drive, select No loader option. (Number 0 defines the virtual loader.) As of 4.4.3 Beefalo V2, you can also select ACSLS, see Configuring ACSLS-Managed Libraries.
- Drive no. in loader: Check the information you got by using slu topology: For example, for the Drive no. in loader with the value 0 you would enter the related persistent name of the drive into the field Device (non-rewinding).
- Device server: The name of the server or RDS to which the drive is connected. The drop-down list displays all available hosts.
- Drive group: Is already selected, based on your previous choice when starting with drive configuration.
- Device (non-rewinding): Based on slu topology output, you have to match the drive's persistent name with the drive number. In our example, for the Drive no. in loader with the value 0 you would insert the persistent drive name Tape2147483644. For details on checking the output, see above section Using slu topology for detecting devices.
- Device Block Size: As of v. 4.4.3 Beefalo V2, it is possible to change the default write density for tapes to achieve better tape performance by using the Device Block Size option. See Setting device block size.
- Tape in drive: If a medium is loaded into the drive, SEP sesam label is displayed.
- Information: If indicated, the messages from the drive hardware are displayed.
- Max. channels: The number of simultaneous backups that can be operated through drives.
- Encryption capable: For already configured drives, it shows whether they are encryption capable. The field is shaded for new drives. Note that SEP sesam provides native support for managing LTO-based encryption; the LTO encryption of tape drives can be enabled on a media pool level. For details, see LTO Encryption.
- Click OK to (re-)configure the drive.
- Repeat the procedure for each drive by entering its persistent name.
|It is recommended to group all drives that belong to the same loader in the same drive group.|
What is next?
- If you have manually configured your backup hardware and created a new drive group, you have to create a new media pool and assign it to the drive group which contains your newly created drives. You can skip this step if you are re-configuring your drives.
- Perform archive adjustment. This is mandatory whenever the contents of a loader carousel is altered. Typically, you have to perform archive adjustment after inserting new media or used media that have not yet been registered (initialized) by SEP sesam. Archive adjustment identifies the media in a loader and synchronizes information with the SEP sesam media archive database. To start the adjustment, select Main Selection -> Components -> Loaders -> select the loader -> Archive Adjustment. For details, see Setting up Archive Adjustment.