Disaster Recovery Architecture: Data Replication to Multi-Cloud and Tape

Duplicating data in different geographical locations is the safest way of ensuring business continuity in the event of disaster, even though this is the most cumbersome method. This requirement, that in some cases has also become a legal obligation, forces businesses to not only acquire and run another expensive infrastructure for the secondary site, but also incur additional running costs for its upkeep (energy, air conditioning, maintenance, upgrades, etc.).

QStar lets you drastically reduce the cost of setting up a disaster recovery site using architecture designed to guarantee data integrity and business continuity at a fraction of the cost of conventional architecture produced for such purposes:

Data Loss

Hardware failure 39%
Human error 27%
Software corruption 14%
Theft 10%
Computer viruses 7%
Others 3%

Disaster Causes

Power outages 31%
Storm 12%
Flood 11%
Other 10%
Hardware error 8%
Bombing 7%
Fire 6%
Power surges 5%
Human error 4%
Network outage 3%
Earthquake 2%
Others 1%
  • Long-term data integrity (10-30 years)

  • Highly-competitive acquisition costs as compared to similar solutions built using only disk-based systems

  • Sizeable reduction in running costs (70-80% compared to disks)

  • Open platform with no lock-in

Data Director

Data mirroring

QStar Data Director provides an innovative way of solving the problem of backing up and restoring massive data storage repositories. By utilizing QStar’s unique event-based mirroring technology, it is no longer necessary to schedule hours for media copy operations. The software mirrors each file system event, which occurs to one or more distinct storage devices in real time. This means that the customer has exact duplicates of the data at any instance in time without the utilization of manpower and time-expensive backup processes. Data Director requires the TDO (QStar Enhanced Archive File System), as TDO writes files as objects mapped to media blocks. By using combinations simulated storage, different configurations can be obtained depending on the customer’s needs.

Real-Time block-based mirroring

Data Director adds the ability to do real-time block-based mirroring, automatic failover and resynchronization of data.
It introduces enhanced data storage resilience to local and wide area networks in the form of data mirroring potentially across different archive mediums using the TDO archive format. This software module is a high performance and cost-effective method of maintaining hot standby data storage. With mirroring, the software provides an efficient means of balancing the read-access loading of the storage sub-system.

Simulated Media Library

The advantage of a Simulated Media Library is the ability to configure a disk-based system to look like a storage library on the network, then either copy that data to a physical storage library or with QStar Data Director, mirror between the simulated library and a physical storage library. By utilizing this technology, organizations are able to overcome some inherent technology limitations and gain the ability, with mirroring now available between disk-based simulated devices and actual removable media devices, to create hybrid archive systems. Hybrid archives have hard disk performance with low-cost, remote, mirrored data protection to removable media libraries. Simulated media is created by specifying a media size on disk. Typically, this is the same capacity as the real media that is also being used. Simulated Media Libraries allow organizations to take advantage of features from QStar Archive Manager and Data Director previously only available for removable media technologies. It allows the user to make copies of data from simulated volumes to removable media volumes automatically with QStar’s “Make Copy” function. This will make distribution copies of data when needed. Simulated Media Library can also be used to test QStar software when the organization has still to purchase a library.

Automatic Rebuild

By making all the mirrored devices self-contained, Data Director provides the means for disaster prevention and recovery. Any device in the storage hierarchy can be completely rebuilt from the mirror device, thus providing enhanced protection from data loss.

WAN and LAN Support

Mirrored sets are not limited to the local server. Other systems on the local LAN or across a broad WAN regardless of their platform can operate as a secondary mirror site. This allows for duplicate sets to be secured by separating the libraries or simulated libraries to other rooms or buildings, or adding another layer of security.

Hot Standby

The hot standby feature of QStar Data Director allows, in the event of a device failure, an automatic switchover to access data on one of the mirror devices without shutting down or reconfiguring the system. Once the failed device has been repaired, it can be brought back on-line and resynchronized as part of the mirror set.


Also known as “Hot Sync”, this feature will resynchronize the mirrored file systems should one be brought off-line because of hardware or other failures. This feature can also be used to take an established QStar Archive Manager set using TDO and later add Data Director to the software package to mirror this set.

Archive Replicator

Archive Replicator

In addition to Data Director, QStar also offers a second option to extend the features of Archive Manager. Archive Replicator can support two, three or four archive targets, synchronously writing data to each. Any combination of archive technologies is supported, although the top speed of individual archive technologies that are blended should be considered. Archive Replicator allows multiple integral volumes to be combined as a single namespace. Data arrives at a primary disk cache location and is immediately migrated to each integral volume designated within the Replicator Migrator. It is possible that one of the replica integral volumes is on another server, perhaps at a different location. In this way it is possible to have a local LTFS tape system, a remote LTFS tape system and cloud storage all configured to write data synchronously to each archive. Read operations are fulfilled from Replica 1 always and data is only requested from Replica 2 in the event that Replica 1 is not available. This means the fastest archive technology should always be configured as Replica 1.

Available Configurations

LTFS to LTFS (Tape to Tape)

The online capacity of the secondary site’s Tape as NAS configuration does not have to match the online capacity of the primary site. The secondary library may have fewer slots and drives, whilst media may be periodically removed (exported) and stored in a secure, offline place, even though remaining virtually online. When using Data Director, employing block-level mirroring, the same tape technology is the only requirement (same drive model). However for Archive Replicator using file replication, the libraries can use different technology, e.g., Oracle T10000X or IBM TS11XX drives on the primary site and LTO drives on the secondary site.


Disk Array to LTFS (Tape)

Another option could use part of an existing storage infrastructure at the primary site. The configuration envisages using the space of a RAID volume by configuring a LUN as virtual tapes. Each virtual tape should have the same capacity as the DR site’s physical medium (e.g. 6 TB for LTO-7). The proprietary file system allows synchronous mirroring between the two sites. For Archive Replicator tape emulation is not required, replicated file-based writes can occur to a NAS RAID and LTFS-based tape library.

Disk Array to LTFS (Tape)

Object Storage to LTFS (Tape)

The above option shows the Tape as NAS solution with Object Storage systems. Object Storage systems are configured to hold a predetermined number of replicated copies. Planning ahead, some organizations require an additional copy on tape due to possible future migration issues and often stipulate use of the LTFS format.
The QStar Archive Replicator module enables data replication from an Object Storage system to a tape library either locally or to a second remote site. This method is often used in the Media & Entertainment and DNA sequencing industries for safe copy which is especially important due to the content’s intrinsic value and the fact that it cannot be recreated again.

Object Storage to LTFS (Tape)

LTFS (Tape) to Cloud

QStar Archive Replicator offers the possibility of using S3 compatible Cloud Storage for the secondary copy. This solution is used by many organizations no second site available for disaster recovery. In these cases, it is advisable to enable data encryption as part of the archiving process.

LTFS (Tape) to Cloud

Related Solutions: Data Replication to Multi-Cloud and Tape

The QStar Kaleidos is an S3-compliant object storage platform that enables enterprises and service providers to build reliable, private, hybrid or public cloud storage environments that deliver reliability, security and unlimited scalability.
Kaleidos offers enterprise-class customers a tremendous reduction in TCO compared with traditional NAS/SAN storage, unlimited scalability, superior data protection and flexibility, while achieving improved customer retention through enhanced service delivery (SLA), reduced acquisition costs, and enhanced agility through global accessibility across all end user devices.
Kaleidos Object Storage is made with standard high-performance capacity servers. QStar Object Storage Manager (OSM) software runs on all server nodes and forms a cluster to provide a single pool of storage resources across all nodes.

QStar LTFS as NAS architecture virtualizes a Tape Library, effectively converting it into network-attached storage – NAS for sharing with multiple users and applications. The solution supports common networking protocols (SMB and NFS) plus S3 compatible API commands and is integrated on either a Windows or Linux server. Files that are stored in a LTFS as NAS environment are retrieved in the same manner as the native operating system, even though the data is actually stored in a Tape Library. Not only do users not realize that the volume (file system) they are accessing was created on tape and not on disk, but, through a sophisticated cache architecture, the read/write data activity is managed so effectively, that performance is comparable to a NAS device. Transparency is such that the architecture is also supported by virtual machine (VM) environments, even though the VM environment is not designed to support tape drives; existing applications installed in a VM can access the Tape as NAS architecture just like a standard NAS disk. Data can be accessed transparently over the network.