Informix Parallel Backup Question ~ Answered: amber (solid confidence) — Multiple consistent, technically precise answers confirm onbar does support parallel backup/restore, name the controlling onconfig parameter, and explain how parallelism maps to dbspaces/drives; no explicit confirmation from the asker.

Advisory only.

Hi All, I have a question for you regarding onbar and backups. I was under the impression that onbar supported parallel backups/restores to/from multiple drives. Does the XBSA agent provided by informix for 3rd party backup vendors also support parallel backups/restores I have looked in the backup restore manual and there is no mention of not supporting this but apparently the vendor has said that it is an inherent limitation of informix. I wanted to be sure of my facts before replying. Any clarification would be much appreciated. Regards Stefan ********************************************************************** This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the sender and delete the material from any computer. You can visit Nylex at http://www.nylex.com.au ********************************************************************** sending to informix-list

On Mon, 7 Mar 2005 12:11:17 +1100, Stefan.Gabriel@nylex.com.au wrote: > >Hi All, > >I have a question for you regarding onbar and backups. I was under the >impression that onbar supported parallel backups/restores to/from multiple >drives. Does the XBSA agent provided by informix for 3rd party backup >vendors also support parallel backups/restores > >I have looked in the backup restore manual and there is no mention of not >supporting this but apparently the vendor has said that it is an inherent >limitation of informix. I wanted to be sure of my facts before replying. > >Any clarification would be much appreciated. > Depends on how you configure onbar and how you execute onbar. Onbar will attempt to backup in parallel unless you execute a 'whole system' backup (much like ontape -s). There is also an onconfig parameter (don't remember exactly which one) which designated a maximum number of backup processes. JWC

<Stefan.Gabriel@nylex.com.au> wrote in message news:1110163093.95298c73eea84eb6da460606e365eefb@teranews... > > Hi All, > > I have a question for you regarding onbar and backups. I was under the > impression that onbar supported parallel backups/restores to/from multiple > drives. Does the XBSA agent provided by informix for 3rd party backup > vendors also support parallel backups/restores > > I have looked in the backup restore manual and there is no mention of not > supporting this but apparently the vendor has said that it is an inherent > limitation of informix. I wanted to be sure of my facts before replying. Yes, it does. It certainly works for HP Data Protector, formerly Omniback.

Neil Truby wrote: > <Stefan.Gabriel@nylex.com.au> wrote in message > news:1110163093.95298c73eea84eb6da460606e365eefb@teranews... > >>Hi All, >> >>I have a question for you regarding onbar and backups. I was under the >>impression that onbar supported parallel backups/restores to/from multiple >>drives. Does the XBSA agent provided by informix for 3rd party backup >>vendors also support parallel backups/restores >> >>I have looked in the backup restore manual and there is no mention of not >>supporting this but apparently the vendor has said that it is an inherent >>limitation of informix. I wanted to be sure of my facts before replying. > > > Yes, it does. It certainly works for HP Data Protector, formerly Omniback. > > BAR_MAX_BACKUP 0 = "I don't care how many threads I kick off" 1 = "I don't want parallelism, but I want the limitations of 'I might as well do an onbar -b -w" 2 or greater = "I will run up to n in parallel" Set BAR_MAX_BACKUP to the number of *available* backup devices -- "I have enough problems remembering my opinions, let alone justifying them." "Sorry, I thought you tapped me."

Hi Stefan, Informix does support parallel back-ups through onbar, and most storage managers also supports this. However this might need some further explanation. What onbar is doing when using this parallel option is that it will backup several (db)spaces at the same time. (So no two streams on one space). The storage manager will need to decide how to store this data, it could do it on one tape drive or several. Most storage managers do not break up streams, so to allow several drives to be used several spaces need to be backupped in parrallel. Make sure all drives have the possibilitie to mount media belonging to the correct pool. Hope this helps, Rob On Mon, 7 Mar 2005 12:11:17 +1100, Stefan.Gabriel@nylex.com.au wrote: > >Hi All, > >I have a question for you regarding onbar and backups. I was under the >impression that onbar supported parallel backups/restores to/from multiple >drives. Does the XBSA agent provided by informix for 3rd party backup >vendors also support parallel backups/restores > >I have looked in the backup restore manual and there is no mention of not >supporting this but apparently the vendor has said that it is an inherent >limitation of informix. I wanted to be sure of my facts before replying. > >Any clarification would be much appreciated. > >Regards >Stefan > > > > >********************************************************************** > > This email and any files transmitted with it are confidential > and intended solely for the use of the individual or entity to > whom they are addressed. If you have received this email in error > please notify the sender and delete the material from any computer. > > You can visit Nylex at http://www.nylex.com.au > > >********************************************************************** > >sending to informix-list