Examine the log files of the connecting and accepting processes
A NetBackup process that initiates a connection is the connecting process, and the target of that connection is the accepting process. The connecting and accepting processes communicate with the respective outbound and inbound vnetd proxy processes. Each proxy process verifies whether the connection is permitted.
The debug logs of the connecting process and the accepting process show their interaction with the proxy. Examine the logs for any status codes and status messages. Also examine the logs for the unique inbound and outbound connection IDs. You can use those IDs if you need to examine the vnetd proxy process logs. You can debug most connections from either host.
For example, the following connecting process log file excerpt shows that a host validation failure prevented a connection:
Peer host validation failed for SECURE connection; Peer host: accepting-host.example.com, Error: 8618, Message: Connection is dropped, because the host ID-to-hostname mapping is not yet approved.., nbu status = 7648, severity = 1
A NetBackup host's names must be mapped to its host ID. If a host name is not mapped properly in NetBackup, communication fails. In this case, you can look up status code 7648 to find the explanation for and recommended action to recover from the error.
If you do not find an indication of a problem by examining the connecting process and accepting process log files, examine the vnetd proxy log files. You can use the connection IDs to find relevant information.