EMC Data Domain deduplication storage systems continue to revolutionize disk backup, archiving, and disaster recovery with high-speed, inline deduplication. By consolidating backup and archive data on a Data Domain system, you can reduce storage requirements by 10-30x, making disk cost-effective for onsite retention and highly efficient for network-based replication to disaster recovery sites.

EMC Data Domain virtual tape library (VTL) software emulates multiple tape libraries over Fibre Channel interface to provide deduplication storage for open systems and IBM environments, and also to provide a supplement for default NAS interface. Data Domain VTL software can emulates multiple tape libraries and tape drives, it avoided the faults associated with the tape.

This article will introduce the tape types and compatibility in DDOS 5.4.

1.    1. Supported tape types of Data Domain VTL in DDOS 5.4

Currently, the supported tape types of Data Domain VTL in DDOS 5.4 are show in below.

                

Tape Code	Default Capacity	Tape Type
L1	100GiB	LTO-1
L2	200GiB	LTO-2
L3	400GiB	LTO-3
L4	800GiB	LTO-4
LA	50GiB	LTO-1
LB	30GiB	LTO-1
LC	10GiB	LTO-1

When a tape is created, a logical, eight-character barcode is assigned that is a unique identifier of a tape. When creating tapes, the administrator must provide the starting barcode. The barcode must start with six numeric or uppercase alphabetic characters (from the set {0-9, A-Z}). The barcode may end with a two-character tag for the supported LT0-1, LT0-2, LT0-3, and LT0-4 tape types.

For example, if we want to create 10 LTO-1 L1 tapes, the assigned first tape’s barcode is ABC100L1, and the final tape’s barcode barcode is ABC109L1.

When you are creating a tape, if no tape capacity is specified, then system will follow the default capacity of tape to create. If tape capacity is specified, it will create tape according to the specified capacity. Create a tape in the GUI as shown in below:

In the GUI, you can see that the tape is created:

You can also use command line to create tape:

#vtltape add [capacity ] [count ] [pool ]

2.    2. The compatibility between tape and tape drive of Data Domain VTL in DDOS 5.4

Data Domain VTL in DDOS 5.4 support IBM LTO-1, IBM LTO-2, IBM LTO-3, and IBM LTO-4, HP LTO-3, HP LTO-4 format tape drives. The compatibility between tape and tape drive as below:

                   

Tape   format	Tape Drive
	LTO-4	LTO-3	LTO-2	LTO-1
LTO-4	RW	—	—	—
LTO-3	RW	RW	—	—
LTO-2	R	RW	RW	—
LTO-1	—	R	RW	RW

RW: Read and Write; R: Read; —: Not compatible

When creating a tape, you need to consider the compatibility between tape and tape drive. Please check the DD OS 5.4 Backup Compatibility Guide found in the Support Portal at https://support.emc.com. 

Through the above description, you can see the Data Domain provides a very convenient GUI menu and CLI commands to create different types and capacity tape devices.

Translator: Leo