By using hotcopy this can be performed on a live subversion repository and will produce a pristine backup.

#!/bin/bash
REPOS_PATH=/var/repos
mkdir -p /backups/weekly
rm -rf /backups/tmp
mkdir -p /backups/tmp/repos
for i in $(ls $REPOS_PATH); do
        /path/to/svnadmin hotcopy $REPOS_PATH/$i /backups/tmp/repos/$i
done
FN=svn.weekly.`date '+%Y%m%d'`.tar.gz
tar -czf /backups/weekly/$FN -C /backups/tmp .

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