Specifications

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Cisco TV CDS 2.5 ISA Software Configuration Guide
OL-24788-01
Chapter 1 Product Overview
Content Delivery System Architecture
Figure 1-3 Content Delivery System Manager User Interface
Resiliency and Redundancy
The TV Content Delivery System is designed to have no single point of failure. The TV Content Delivery
System incorporates redundancy at several levels within the architecture. These levels of redundancy
eliminate any customer impact from potential failures of Vault disks, Vault servers, Streamer disks,
Streamer servers, ISV servers, Ethernet connections, processors, and power supplies.
Each server constantly monitors the state of its peers. The TV CDS unique resource pooling and
auto-failover techniques allow all servers in the network to actively contribute to satisfying storage and
streaming demand at all times. If a server fails, the load is instantaneously redistributed among the
surviving servers, ensuring continuity of service.
Vault Disk Redundancy
The Vault server protects content through full 1:N redundancy. If a disk fails, the data is available from
a redundant server, spreading the load and optimizing the bandwidth. Additionally, the regeneration of
the redundant content utilizes the bandwidth of the whole Vault array rather than just the disk bandwidth
available inside a particular server, significantly reducing the rebuild time. The need to replace the failed
drive is not time critical in the least, making quarterly replacement of any failed Vault drives feasible.
Mirroring
The primary method to protect the content against loss because of hardware failure is mirroring. Content
is stored on a Vault and, based on the policy, it is mirrored to other locations in the Vault array. The
number of mirrored copies is configurable. There are three types of mirroring:
• Local mirroring
• Mirroring within an array
• Array mirroring (from Vault Group to Vault Group)