Updated: March 13, 2018
The following service description applies to SafeHaven version 4.0. The service description for SafeHaven version 5.0 can be found at CenturyLink Cloud Service Guide.
SafeHaven provides a suite of IT disaster recovery and inter-site migration services. SafeHaven is deployed by CenturyLink Cloud for its customers to deliver DRaaS. SafeHaven system components follow a structural hierarchy in the following order:
Each SafeHaven cluster can service up to 64 data centers. The data centers may be any combination of dedicated data centers and Cloud virtual data centers. Each data center within the cluster can include both active Protection Groups and replica instances of remote Protection Groups. Each subscriber organization is provisioned with a distinct SafeHaven cluster.
The SafeHaven console is a rich Java client application which should be installed on all desktop or laptop computers that will be used for SafeHaven administration. All communication between the SafeHaven console and the CMS are encrypted over SSL. Administrators can perform point-and-click recovery operations upon individual virtual machines, groups of servers and data drives, or entire data centers. Recovery operations include:
Central Management Server (CMS)
Each SafeHaven cluster includes a single active CMS. The CMS is a SafeHaven virtual appliance that:
Data Center Layer
The data center layer includes the set of data centers provisioned within the SafeHaven cluster.
SafeHaven classifies data centers based on the API used for orchestration of recovery operations and recognizes three data center types:
This layer includes all SRNs provisioned within the SafeHaven cluster. Each SRN is associated with a parent data center as shown in the SafeHaven hierarchy. A given data center may include an arbitrary number of SRNs. The SRN virtual appliance is responsible to:
SRNs replicate at the LUN level transmitting updated blocks for each Protection Group to a peered SRN in a remote data center. Although each active Protection Group has a replica in only one other site, an SRN may support a set of Protection Groups that each have replica instances in distinct remote data centers.
Additional Storage Requirements:
A Protection Group is set of servers and hard disks grouped by SafeHaven that failover, failback, and rollback together to the same instance in time and are shutdown and brought-up according to a prescribed recovery plan. Each Protection Group corresponds to a distinct set of servers and hard disks replicated to a remote site by a parent SRN. When protecting a multi-tiered application, administrators should provision a Protection Group that includes the set of all servers and hard disks that participate in the multi-tiered application. SafeHaven is set up to allow the applicable systems to recover via a remote data center with mutually consistent data images as they were at specific instances in time.
Write traffic for each protected VM and hard disk is locally and synchronously mirrored within the production data center so that it is written both to the primary data store and also to a local SRN. For Windows Server Operating Systems 2003 and later, the SafeHaven local replication agent is employed and in Linux Operating Systems, Logical Volume Manager 2 is employed.
SafeHaven checkpoints correspond to LUN-level Copy on Write snapshots and are block-consistent representations of a Protection Group at an instant in time. For many users, CenturyLink recommends that the storage allocated to the checkpoints be approximately thirty percent (30%) of the storage allocated to the Protection Group itself.