5 Complex networks: challenges and solutions

Most information about Ignite server set up assumes a simple network consisting of one subnet where the server supports network boot and installation. This simple network configuration is assumed so documentation can be clear and concise.

Often, real network environments are significantly more complex. Configuring an Ignite server to operate correctly in a complex network configuration requires special consideration of network topology.

This chapter identifies some types of complex network challenges and approaches to handle these challenges.

This chapter focuses on Integrity systems only.

How to use this chapter

Data centers have unique requirements, constraints, and network topology. It is likely you will have multiple challenges when creating a total solution for system installation and recovery, which will require you to implement multiple solutions for your site.

To help explain network topology, an example complex network diagram will be used that presents multiple challenges. This example network will be referenced throughout the complex networking chapters.

Knowledge of network boot and OS installation steps will help you understand this chapter. Most often, boot and installation is performed by one server. When considering complex network solutions, it sometimes make sense to use separate systems for boot and installation, or to switch servers during the boot process. See the “How Ignite works” (page 18) section for network boot and OS installation steps information.

Network boot and installation relies on several protocols that are not detailed here. See “Ignite-UX server ports” (page 84) for protocol and port information related to Ignite phases of operation.

It is assumed you have a working knowledge of DHCP, PXE, bootp, and TFTP.

Complex network challenges

In a complex network configuration, it is often preferable to manage one master Ignite server and use that server to support installation for all subnets. A central server simplifies administration and helps ensure all systems are managed with consistent installation and recovery. The challenge is to have a central Ignite server support network boot for all your required subnets, handle installation, and coexist with any other network boot servers.

The following diagram illustrates a complex network with multiple subnets (10.1.1 and 10.2.1) connected to the Ignite server (hpignite), remote systems (hpuxsysa and hpuxsysb) that use a boot helper system (iuxboot), a system (hpuxsysz) on a separate subnet without a boot helper, and another boot server (sysrdp) on the same subnet as the Ignite server. Systems on the same subnet (10.1.1 or 10.2.1) as the Ignite server are HP-UX systems (hpuxsys1, hpuxsys2, and hpuxsysx), a Linux system (linuxsys2) and a Windows system (winsys1). This diagram will be used as an example network configuration throughout the complex network chapters.

48 Complex networks: challenges and solutions