DOCUMENTATION: A NetBackup 6.0 mixed master/media server environment requires at least NetBackup Enterprise Server / NetBackup Server 5.0 Maintenance Pack 1 (MP1)

Article:TECH42866  |  Created: 2005-01-26  |  Updated: 2006-01-09  |  Article URL http://www.symantec.com/docs/TECH42866
Article Type
Technical Solution


Environment

Issue



DOCUMENTATION: A NetBackup 6.0 mixed master/media server environment requires at least NetBackup Enterprise Server / NetBackup Server 5.0 Maintenance Pack 1 (MP1)

Error



cannot connect on socket (25)

Solution



Manual:  NetBackup (tm) 6.0 System Administrator's Guide

Page:  n/a

Modification Type:  Supplement

Modification:

NetBackup Enterprise Server (tm) / NetBackup Server (tm) 6.0 will be able to communicate with media servers that are running older revisions of the NetBackup software. Due to changes made to the vnetd daemon, the minimum required version for a NetBackup 5.0 media server is Maintenance Pack 1 (MP1). These changes were introduced in NetBackup 5.0 Maintenance Pack 1 and were incorporated into NetBackup 5.1. There is no minimum required maintenance pack level for NetBackup Enterprise Server / NetBackup Server 5.1.

A restore from a NetBackup 6.0 master server that uses a storage unit attached to a NetBackup 5.0 media server will fail with a status 25 when the following conditions are met:
  • The master server is running NetBackup Enterprise Server / NetBackup Server 6.0
  • The media server is running NetBackup Enterprise Server / NetBackup Server 5.0
  • The media server and the client are the same system

The restore will fail with a Status 25 because the master will not be able to make a successful connection to vnetd on the 5.0 media server.  With NetBackup 6.0, the vnetd daemon is used for all connections between the master and a 5.0 media server for restores. Without NetBackup 5.0 Maintenance Pack 1 installed on the media server, the system will be unable to handle the vnetd connection properly.

The Detailed Status tab for the restore job in the Activity Monitor will show the errors:
2005-7-15 1:00:18 - Warning bprd (pid=1234) Restore must be resumed prior to first image expiration
2005-7-15 1:00:18 - end Restore; elapsed time 0:07:12
cannot connect on socket (25)

As a short term workaround, the NOSHM touch file can be enabled and should allow the restore to complete successfully.  This touch file disables the use of shared memory and changes the behavior of the vnetd daemon.  

To disable the use of shared memory, create the following file on the NetBackup 5.0 media server.  

Note: Enabling this file can affect the performance of backups and restores, so this should only be used until the media server can be upgraded to 5.0 Maintenance Pack 1 or NetBackup 6.0.
# touch /usr/openv/netbackup/NOSHM

Each time a restore runs, NetBackup checks for the existence of this file.  As a result, no services need to be stopped and started for it to take effect.  Once the restore is complete, remove the NOSHM touch file.

This will affect restores to the NetBackup 5.0 media server or any other operation that uses vnetd.  The 5.0 media server will need to be running a minimum of Maintenance Pack 1 in order to be supported in this mixed master/media environment. To download the latest update for NetBackup 5.0, visit the Support Web site:
 http://support.veritas.com/menu_ddProduct_NBUESVR_view_DOWNLOAD.htm



Supplemental Materials

SourceETrack
Value401238
DescriptionMaster server 6.0 and media server 5.0GA - backup to tape succeeds but restore from tape fails.

SourceError Code
Value25
Descriptioncannot connect on socket

SourceClearDDTS
Value48456
DescriptionRestores using shared memory fail when vnetd is used on 5.0 GA

Legacy ID



278153


Article URL http://www.symantec.com/docs/TECH42866


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