Troubleshooting guide

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Networks and Hostnames

In a configuration with multiple networks and clients with more than one hostname, the

NetBackup administrator must configure the class entries carefully, at all times

considering the network configuration (physical, hostnames and aliases, NIS/DNS,

routing tables, and so on). This is especially true if the desire is to direct backup and

restore data across specific network paths.

For a backup, NetBackup connects to the host name as configured in the class. The

operating system’s network code resolves this name and sends the connection across the

network path defined by the system’s routing tables. The bp.conf file is not a factor in

determining this.

For restores from the client, the client connects to the master server. For example, on a

UNIX system, the master server is the first one named in the

/usr/openv/netbackup/bp.conf file. On a Windows system, the master server is

specified on the Servers tab of the Specify NetBackup Machines dialog box (to open this

dialog, start the NetBackup client user interface and click Specify NetBackup Machines on

the Actions menu). The network path to the server is determined by the client’s network

code that maps the server name to an IP address.

Upon receipt of the connection, the server determines the client’s configured name from

the peername of its connection to the server.

The peername is derived from the IP address of the connection. This means that the

address must translate into a host name (using the gethostbyaddr() network routine).

This name is visible in the bprd activity log when a connection is made as in the line:

Connection from host peername ipaddress ...

The client’s configured name is then derived from the peername by querying the bpdbm

process.

The bpdbm process compares the peername to a list of client names generated from:

1. All clients for which a backup has been attempted

and

2. All clients in all classes