Kbase P172165: Users hang when online probkup waits for next device
| Autor |
Progress Software Corporation - Progress |
| Acesso |
Público |
| Publicação |
24/08/2010 |
|
Status: Unverified
SYMPTOM(s):
Users hang when online probkup waits for next device
After providing the next device name the database frees up
Not all users will hang
Promon User Control screen shows some users waiting on BKEX
FACT(s) (Environment):
All Supported Operating Systems
Progress 8.x
Progress 9.x
OpenEdge 10.x
CAUSE:
A very brief description of how probkup online works is that at the start of the backup it will freeze the database, flush any active blocks and take a snapshot of the bi file. When it has finished backing up the bi file it allows user activity to continue.
While the backup is running, if any user tries to modify a database block that has not been backed up, probkup will write the original version of that block to the backup media before it allows the user to update that block (because the backup needs to maintain the snapshot of the database at the time the backup was started).
The reason for some users to hang when the backup is requesting the next device is that a user is attempting to modify a block that has not already been backed up. Because the backup can't continue while it is waiting for the next device, it can't write out the original block to tape and therefore the user will remain hung until the backup can continue.
FIX:
Automate the backup by creating a script that can automatically insert subsequent device names.
Obviously this will not work if there is only a single tape device, in which case it may be a better idea to backup the database to disk and then use an O/S backup such as tar or cpio to backup the probkup files to tape.