Highly Available HP-UX Internet Services (May 2008)

HP ServiceGuard contains an excellent failover mechanism so that the applications can

recover from failures immediately and without any downtime. The HP ServiceGuard

failover architecture assigns an IP address called the "floating IP address" or "relocatable

IP address" to the application package to enable the IP address to move from one cluster

node to another in case of node failure. Therefore, applications can access the package

using the floating address of an application without knowing the current node's

stationary IP address or hostname. In a cluster of more than two systems, multiple

systems can fail with the surviving systems taking over for the failed ones. In cases

wherein each network adapter supports multiple IP addresses, failover occurs efficiently

without requiring other applications to be stopped.

This white paper addresses the following topics:

• “Configuring HP ServiceGuard” (page 6)

• “Configuring the Monitor and Startup/Stop Scripts” (page 6)

• “Configuring DNS with HP ServiceGuard” (page 8)

• “Configuring Sendmail with HP ServiceGuard” (page 10)

• “Configuring FTP with HP ServiceGuard” (page 16)

• “Appendix A: Sample Scripts for DNS” (page 19)

• “Appendix B: Sample Scripts for Sendmail” (page 21)

• “Appendix C: Sample Scripts for FTP” (page 28)

Configuring HP ServiceGuard

HP ServiceGuard is designed to work in conjunction with other high availability

products, such as MirrorDisk/UX or VERITAS Volume Manager, Event Monitoring

Service (EMS), disk arrays, and HP-supported uninterruptible power supplies (UPS),

such as HP PowerTrust. HP recommends customers to configure these products with

HP ServiceGuard to avail a high degree of availability. Before configuring a product

to work in an HP ServiceGuard environment, the HP ServiceGuard environment must

be set up in the system. For information on configuring HP ServiceGuard with different

products, see the relevant documents listed at:

http://docs.hp.com/en/ha.html

This white paper describes the procedure to configure BIND, FTP, and Sendmail with

HP ServiceGuard to provide high availability in HP-UX Internet Services.

Configuring the Monitor and Startup/Stop Scripts

With HP ServiceGuard, application services and the resources required to support

applications are bundled into an application package, which is a basic unit managed

and moved within an enterprise cluster. These application packages describe how to

start and stop an application and the required resources, and ServiceGuard monitors

nodes, networks, and processes. If a node, network, or process fails, the application

package can be configured to automatically stop and restart (along with the required