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| New 1U rackmount chassis and power supply design passed Intel rigid testsing and being adopted in the Intel hosting center |
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| CAI starts manufacture and assembly rackmount based network appliance for Italy based company Petral. |
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| CAI and Allen Bradley agreed to let CAI manufacture rackmount chassis for its industrial and military computing division |
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BACKING UP DATA IN A HIGH AVAILABILITY ENVIRONMENT With data centers moving more towards 24 x 7 operations it is becoming increasingly difficult to find a window when file systems can be backed up in a consistent manner. There are many problems associated with backing up files that are active. In fact, some backup utilities will refuse to back up files that are open for output. In today's environment it is often not possible to interrupt access to the data in order to back it up.
A good solution to this problem is to use the capability of a product called OnLine Journaled File System, also known as AdvJournalFS. With Online JFS, you can create a snapshot of a file system and backup the snapshot while the original file system is active. The snapshot logical volume is created with new options to the mount command. No data is actually copied to the snapshot logical volume unless the original copy is modified. Only those blocks of the file system that are modified need ever be copied to the snapshot. Therefore, the snapshot logical volume can be much smaller than the original. The backup is taken of the snapshot, which presents a "frozen" view of the file system. When the backup is complete, the snapshot is unmounted and the logical volume can be reused as a snapshot for another file system. The following example demonstrates how to use OnLine JFS to backup the /home file system: 1. Create a logical volume to be used as a snapshot of the /home file system. The snapshot does not need to be as large as the original file system. For example, if /home is 500MB and you estimate that at most, 10% of the file system will be modified during the backups, your snapshot only needs to be 52MB (a multiple of the LVM 4MB extent size): lvcreate -L 52 -n snaplv /dev/vg01 2. Create a mount point for the snapshot: mkdir /home.bkp 3. Create the snapshot using the mount command: mount -F vxfs -o snapof=/home /dev/vg01/snaplv /home.bkp At this point the files that you would see when traversing the /home.bkp directory would be identical to the files under /home. /home.bkp is read only, whereas the files under /home can be modified. Initially, none of the data from /home is actually copied to snaplv. This will occur only when, or if, data in /home is modified. 4. Now it's time to back up the snapshot. I recommend performing the backup using relative path names. That way, files can more easily be restored to /home. You can use most of the standard backup utilities to back up the snapshot. In this example, we'll use fbackup: cd /home.bkp 5. When the backup completes, unmount the snapshot: cd /
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