Date published: January 6, 2012
Products: Portlock Storage Manager Client and Portlock Storage Manager for NetWare.
Environment: Portlock Storage Manager Client is imaging a NetWare 6.5 SP7 server using the Image NetWare Server wizard and the server abended during the image.
Issue #1: The NetWare server abended when performing an online image.
Issue #2: After rebooting the server, a pool snaphot existed that prevented another online imaging attempt.
#Issue #3: After completing the Image NetWare Server wizard, an error message about an invalid file handle was reported.
Resolution for Issue #1. Install NetWare 6.5 SP8 and N65NSS8C. Portlock Storage Manager uses Novell's Snapshot feature to image NSS Pools while they are active with mounted volumes. This features requires SP8 and the post SP8 NSS patch.
Novell is constantly changing download URLs. If you have a problem with the above links search for the following file names with Google. Select a download location that is from Novell and not a third party:
Note: Prior to installing a service pack, we recommend using Portlock Storage Manager to image your server. This way if a serious problem appears after installing SP8, you can restore your server back to its current configuration. In this case, do an offline image.
Note: If you do not want to install SP8, then use the offline imaging feature. Do not select a Pool for snapshots in the image wizard.
Resolution for Issue #2: Delete the snapshot. After the server abended the snapshot that Portlock Storage Manager created was not deleted.
Start Portlock Storage Manager on the server:
To load Portlock Storage Manager on the server type the following command at the server console:
NetWare also provides snapshot commands at the server console:
Resolution for Issue #3: Using the Novell Client, relogin to the NetWare server. When a NetWare server abends, the Novell Client sometimes does not reconnect to the NetWare server once it reboots. In some cases, a reboot of the workstation is required to clear the Novell Client connection table.
Data backup and Recovery is probably one of the most essential tasks as a system administrator. In the event of a disaster, a successful recovery of data and services will determine whether you will be getting your raise or you will be looking for a new job. Yet, many administrator do not pay much attention to backup and recovery strategy. Many put absolute faith in the backup software logs that declares that the backup is completely successfully for the day. However, we forget that a successful backup is not the end goal but a successful restore in an event of a disaster is the end goal. Herein lies the trap of false security. In the event of disaster, without a clear recovery and tested plan, administrator may spend the next 2 days trying to figure why data cannot be recovered. It does not help that your users and boss are breathing down your neck.
Novell SnapShot Backup feature alleviates problems encountered when backing up open files. SnapShot creates a virtual image or snapshot of a volume at a particular point in time. Once the snapshot is created, further changes are stored as "deltas" from the snapshot so that delta data plus the active volume can create a complete replica of data storage. Novell's innovative SnapShot approach allows a pool snapshot to be created in 10 to 20 percent of the size of the original pool and in a minimum amount of time. NetWare can support up to 500 active snapshots on a given NSS storage pool (500 different snapshots in time on the disk).
Snapshots provide an instant copy of volume's data that otherwise would be difficult to backup because of open files. Novell's "freeze/thaw" technology provides a consistent data set that facilitates non-disruptive backups. As contrasted to a traditional, full-data copy of the pool, the block-level copy only takes a moment to create and occurs transparently to the end user.
The Novell freeze/thaw interface manages snapshot events so that applications (databases, GroupWise®, etc.) are informed that a snapshot is about to take place. Applications then ready file system data by getting it consistent and flushing pending transactions. The application indicates its frozen or ready state to the NSS system where buffers are flushed and open disk files are rendered consistent. The snapshot then takes place in less than two seconds and the system indicates that the applications are free to "thaw" and continue. No longer do administrators have to take down a database or mail server to get a consistent backup. Freeze/thaw interfaces are published and being consumed by Novell and its third party partners so that snapshot solutions provide consistent data when done in a SAN or storage array as well as at a host.
Snapshots can be used as part of a disaster recovery plan and archived for online or near-line access. Applications or users can proceed to work from the snapshot in the event that the original files are inaccessible.
Portlock Online Imaging provides block based imaging for NetWare 6.5 SP8 or later NSS Pools while they are active with mounted volumes. Portlock Online Imaging depends upon Novell SnapShot Backup. An NSS Pool, which can be empty, is used by Novell SnapShot Backup to store the deltas during an image command. Portlock Storage Manager automatically freezes the selected pools, creates the snapshots, images the pools, thaws the selected pools and finally deletes the snapshots.
Make sure that you don't have pool corruption in the pool that is holding the snapshot. In the above example, compete an "nss /PoolVerify" on the "TEST" pool.
If you see any warnings or errors with the above (and they are not corrected by a Pool Rebuild), report this to Novell as you have a setup that does not support snapshots correctly or there is a bug in Novell's code supporting snapshots.
To see the help screen for NetWare's "mm" commands type "help mm" at the console.
To delete the above snapshot: "mm snap delete sys_snap".