NetBackup 4.5 Troubleshooting Guide for Windows - Symantec

NetBackup 4.5 Troubleshooting Guide for Windows
Networks and Hostnames B
In a configuration with multiple networks and clients with more than one hostname, the
NetBackup administrator must configure the policy entries carefully, at all times
considering the network configuration (physical, hostnames and aliases, 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 policy. The
operating system’s network code resolves this name and sends the connection across the
network path defined by the system’s routing tables.
For restores from the client, the client connects to the master server. 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 debug 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 (NetBackup Database Manager service).
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 policies
The comparison is first a simple string comparison which, if successful, is verified by
comparing hostnames and aliases retrieved by using the network function
gethostbyname().
NetBackup 4.5 Troubleshooting Guide for Windows
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