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Article ID: 199272


Updated On:


CA Spectrum


We recently upgraded the Spectrum from 10.3.1 to 10.4.2 and we noticed a poor/low compression on the DDMdb backup file.

As per the documentation we have update the post_olb_script for ddmdb backups:

./ -f $backup_dir/db_$time_string.DDMDb > $backup_dir/ddm_backup.log 2>&1

The size of the DDMDB backup file (.mbi) has increased almost 4 times as compared to old backups in 10.3.1 (from 420 MB to 2 GB) using the above script, is this normal?


The default mysql compression method does not compress enough


Release : 10.4.1

Component : Spectrum Core / SpectroSERVER


There is an increase in size due to the change in mysql from myisam to innodb. Innodb is more of a transactional db and the event tables are broken up into days. This is normal as noted here:

However, the savefile is rather large with the default compression.  To enable better compression, edit the $SPECROOT/SS/DDM/ and change this entry:

Locate this section in the file:

$cmd = "$MYSQLBACKUP --defaults-file=$MYSQL_CONF --compress --user=$USERNAME --password=$PASSWORD  --backup-dir=$backup_dir  --backup-image=$backup_image --include-tables=\"^ddmdb\.\" --use-tts  backup-to-image $REDIRECT_NULL_DEV";

And replace this parameter - To use --compress-method=lzma:

$cmd = "$MYSQLBACKUP --defaults-file=$MYSQL_CONF --compress-method=lzma  --user=$USERNAME --password=$PASSWORD  --backup-dir=$backup_dir  --backup-image=$backup_image --include-tables=\"^ddmdb\.\" --use-tts  backup-to-image $REDIRECT_NULL_DEV";


This will be changed in a future release of Spectrum.

Additional Information

Also review this KB article:

Failure in the mysqlbackup during the execution of post_olb_script does not generate event and alarm