Network: Overview

In a CommCell instance, the hardware components, such as the CommServe computer, client, MediaAgent, and storage devices (including libraries), are interconnected by a data network. The CommCell instance uses this network to transmit data and control information.

In addition to the hardware devices, the network consists of the components listed here for quick and lossless transmission of information.

CommCell Network Requirements

All CommCell computers (CommServe, MediaAgent and client) must be interconnected by a network that supports TCP/IP protocol. The network must also meet certain requirements for the CommCell instance to function fully, such as having a unique name for each NIC in the Domain Name Server, supporting Internet Protocol versions IPv4 and IPv6, and having TCP ports assigned to CommServe services. See CommCell Network Requirements.

Client Connectivity

Before running an operation in the CommCell instance, you can check the connectivity between the client and the CommServe host from the CommCell Console or from the command prompt. See Client Connectivity.

Data Pipe

In a CommCell network, Data Pipes transfer data between the client and the MediaAgent controlled by parameters such as Data Pipe Buffers, Network Agents and Application Read Size. See Data Pipe.

Data Interface Pairs

A Data Interface Pair (DIP) is an exclusive network route between two CommCell computers that enables faster communication between them. DIPs are supported through both individual clients, and client groups. See Data Interface Pairs.

Encrypted Challenge and Reply

All CommCell communications between the CommServe and client use encrypted challenge-and-reply to validate the hosts involved.


Various CommCell components can be separated by a firewall. These components can be configured to seamlessly communicate with each other through the firewall while performing operations such as backup and restore. For detailed information on configuring the firewall and the components that must communicate through it, see Firewall.

Network Bandwidth Throttling

Network Bandwidth Throttling is useful for regulating network traffic, and minimizing bandwidth congestion between the clients and MediaAgents in a CommCell network. See Network Bandwidth Throttling.

Network Password

The CommCell network password is an internal security measure for ensuring that communication occurs only between the CommCell computers. By default, the software assigns each computer in the CommCell a different password which can be later changed by the administrator, if required. See Network Password.

Network Tools

Network tools allow you to verify network connectivity between the CommCell components, troubleshoot network connectivity between any two CommCell computers, and change the network password of one or more clients. See Network Tools.

Robust Network Layer

The Robust Network Layer periodically tests connectivity between CommCell components, and indicates loss of connectivity during an operation. Robust Network Layer describes the details and settings of this feature. 

VPN (Virtual Private Network) Support

VPN support in the SnapProtect software provides services that enable controlled access to internal services by routing VPN traffic to and from host computers within a CommCell environment.