NBU version of master?
Are there any media servers doing the backup, or is the master also a media?
If media servers are being used, what O/S and NBU versions?
Is the client in a DMZ?
Try the following:
Step 1) Have you checked for dusplicate IPs, with...
$ nslookup master-ip
$ nslookup master-ip
$ nslookup client-ip
$ nslookup client-ip
If the results of the second lookup are different, then you have duplicate IPs and the NetBackup won't work.
Step 2) Does the client have the master server defined as the primary "SERVER"?
Get your Linux froods to run the following on the client:
$ bpgetconfig SERVER
...and there must be at least one entry of:
SERVER = master-name
...if it doesn't exist, or is not the master server name then get your Linux dudes to:
2a) Create a text file containing one line:
SERVER = mastername
2b) Update the client with:
$ bpsetconfig -h clientname myfile.txt
To test whether the master can see the client, you don't need to attempt test backups, you can simply:
$ bpgetconfig -g clientname
...to show the client version. If this command files, then backups/restores will fail.
HTH, Regards, Dave.