Redhat prepare scripts compresses MySQL backup

The incremental backups on some cluster head nodes are growing quite
large, and most of the churn is the uncompressed MySQL dumpfile which
changes with every backup and can be over 1GB. This commit compresses
that data, which reduces the size of the file by 90% on at least one
machine.

ROOT/DEBIAN/control

@@ -3,6 +3,6 @@ Priority: optional
 Section: otherosfs
 Maintainer: Chemistry COs <support@ch.cam.ac.uk>
 Architecture: all
-Version: 0.9-ch98
+Version: 0.9-ch99
 Depends: zfs-dkms, postgresql-13 | postgresql-9.5 | postgresql-9.4 , liblockfile-simple-perl, libdbi-perl, libjson-perl, libzfs-perl-chem, libnet-openssh-perl, libdbd-pg-perl, mbuffer, rsync, nfs-kernel-server, pv, libwww-curl-perl, libformat-human-bytes-perl
 Description: a backup system using ZFS (repository 'backup-scheduler')

ROOT/etc/chem-zfs-backup-server/zfs-rsync.d/prepare-redhat

@@ -31,7 +31,7 @@ ssh root@$SERVER "
 # Dump MySQL, if the root user has access
 if [ -f /etc/my.cnf ] ; then
  SOCKET=`awk ' BEGIN {FLAG=0} (\$0 ~ /^\[/) {FLAG=0} (\$0 ~ /^\[mysqld\]/) {FLAG=1} (\$1=="socket" && FLAG==1) { print \$3 ; } ' </etc/my.cnf`
- [ -S \$SOCKET ] && which mysqldump >/dev/null 2>&1 && mysqldump --all-databases >/var/adm/backup/mysql
+ [ -S \$SOCKET ] && which mysqldump >/dev/null 2>&1 && mysqldump --all-databases | gzip -c >/var/adm/backup/mysql.gz
 fi
 
 # Dump PostgresSQL, if the postgres user has access