Consultor Eletrônico

Status: Verified

GOAL:

Constraints When Using One After-Image Extent.

GOAL:

What should I note when I consider using only one AI extent?

GOAL:

What should I consider when I use only one AI extent?

FACT(s) (Environment):

Progress 8.x

FIX:

How can users best manage after-imaging with 1 AI extent? Following are some constraints to understand when working with one extent.

1) 2 Gig limit: While using the Database in single-user or multi-user mode, the after-image extent (for example, sports.a1) will grow.  Keep in mind that, as for any Progress extent prior to V9.1C, the size of sports.a1 must never grow over the 2 Gig limit.

2) No on-line backup:  You cannot run an on-line backup while having just one after-image extent since it generates an automatic ai extent switch. You would get the message:  Switch to new ai extent failed. (3669)

3) Cannot stop ai with "_mprosrv" running. You cannot stop the after-imaging while a "_mprosrv" is running against the database.  This will generate error 276.


In later versions, rfutil db-name -C aimage aioff can be used to stop AI while server is running

4) While Running backup, you need to stop the after-imaging prior to running a backup. You can either do the following:


a) Run a Progress backup (via "probkup") or an OS backup

b) Do not restart after-imaging prior to running either a "probkup" or a "rfutil -C mark backedup".  This will generate error 834.

WARNING: Should you not backup the after-image extent prior to restarting the after-imaging, then you would not get any error but you would "lose it". Progress has no tool to backup the after-image extent, you need to use an OS command such as:


> cp /usr3/ver83/sports.a1 /saveai/sports.1a1

-- Restoring the Database:

Should you need to restore the "sports" Database up to a certain time, then you would run the following commands:


> prorest sports /savebkup/sports.1bk1  
> rfutil sports -C roll forward endtime <yyy:mm:dd:hh:mm:ss> -a /saveai/sports.1a1