Re: can not allocate log, archival required..

Tina Mourad wrote:

> I get the DOS window warning "Oracle instance xxx can not allocate
> log, archival required".
>
> My init.ora does have the line
> LOG_ARCHIVE_START = TRUE
>
> thanks in advance..
>

my guess is that you one/many of the following:

1. no free space in the log_archive_dest location
2. very small online redo logs with few groups (little redo capacity)
3. online redo, datafiles and archived redo on the same filesystem on a single RAID 5 volume.

Determine the quantity of redo generated per day during the workday. divide that by 8 - that is how large you want your online redo logs to be (say 128M for example).
Create at least 4 online redo log groups of that size: - 1 member per group if you have little I/O capacity and non-stringent uptime requirements.
- 2 members per group (on separate physical disks, separate RAID controllers or controller channels, at least) if possible - 3 members per group if you had the chance to specify the storage subsystem.

Your system will have had to have generated 4x the regular hourly rate to fill all of the online redo logs.

The archiver process will be able to read from all members in a group in a round-robin fashion, thus speeding the archiving of online redo logs.

The only downside is that the size of your cold backup sets will increase. If you're only using hot backups, then no matter.

Disks are cheap, Oracle CPU licenses are expensive.

Paul Received on Sat Mar 23 2002 - 23:20:54 CST