DL1300 Appliance
Setting up your environment
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The source core copies the recovery points of the protected agents and then asynchronously and continuously
transmits them to a target core at a remote disaster recovery site. The off-site location can be a company-
owned data center (self-managed core) or a third-party managed service provider’s (MSP’s) location or cloud
environment. When replicating to a MSP, you can use built-in work flows that let you request connections and
receive automatic feedback notifications. Possible scenarios for replication include:
•
Replication to a Local Location— The target core is located in a local data center or on-site location, and replication is
maintained at all times. In this configuration, the loss of the Core would not prevent a recovery.
•
Replication to an Off-site Location— The target core is located at an off-site disaster recovery facility for recovery in the
event of a loss.
•
Mutual Replication— Two data centers in two different locations each contain a core and are protecting agents and
serving as the off-site disaster recovery backup for each other. In this scenario, each core replicates the agents to the
Core that is located in the other data center.
•
Hosted and Cloud Replication— AppAssure MSP partners maintain multiple target cores in a data center or a public
cloud. On each of these cores, the MSP partner lets one or more of their customers replicate recovery points from a
source core on the customer’s site to the MSP’s target core for a fee.
Parent topic
Setting up your environment
If the bandwidth between the source core and the target core cannot accommodate the transfer of stored recovery
points, replication begins with seeding the target core with base images and recovery points from the selected
servers protected on the source core. The seeding process can be performed at any time, as part of the initial
transfer of data to serve as the foundation for regularly scheduled replication, or in the case of re-instating
replication for a previously replicated machine whose replication had been paused or deleted. In this case, the
Build RP Chain option would let you copy not-yet replicated recovery points to a seed drive.
When preparing for replication, you should consider the following factors:
•
Change Rate—The change rate is the rate at which the amount of protected data is accumulated. The rate depends on
the amount of data that change on protected volumes and the protection interval of the volumes. If a set of blocks change
on the volume, reducing the protection interval reduces the change rate.
•
Bandwidth— The bandwidth is the available transfer speed between the source core and the target core. It is crucial
that the bandwidth be greater than the change rate for replication to keep up with the recovery points created by the
snapshots. Due to the amount of data transmitted from core to core, multiple parallel streams may be required to perform
at wire speeds up to the speed of a 1 GB Ethernet connection.
NOTE:
Bandwidth specified by the ISP is the total available bandwidth. The outgoing bandwidth is
shared by all devices on the network. Make sure that there is enough free bandwidth for replication to
accommodate the change rate.
•
Number of Agents— It is important to consider the number of agents protected per source core and how many you plan
to replicate to the target. DL1300 lets you perform replication on a per-protected server basis, so you can choose to
replicate certain servers. If all protected servers must be replicated, this drastically affects the change rate, particularly
if the bandwidth between the source and target cores is insufficient for the amount and size of the recovery points being
replicated.
Depending on your network configuration, replication can be a time-consuming
process.
The Maximum Change Rate for WAN Connection Types is shown in the table
below with examples of the necessary bandwidth per gigabyte for a reasonable
change rate.
