postinst is in dpm-server-postgres 1.10.0-2.
This file is a maintainer script. It is executed when installing (*inst) or removing (*rm) the package.
The actual contents of the file can be viewed below.
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 | #!/bin/sh
set -e
updatedpm () {
    [ -r /etc/default/dpm ] && . /etc/default/dpm
    [ -z "$DPMCONFIGFILE" ] && DPMCONFIGFILE=/etc/DPMCONFIG
    [ -r $DPMCONFIGFILE ] || return 0
    dpmcfg=$(cat $DPMCONFIGFILE)
    cfg1=$(echo $dpmcfg | cut -f1 -d@)
    cfg2=$(echo $dpmcfg | cut -f2 -d@ -s)
    user=$(echo $cfg1 | cut -f1 -d/)
    passwd=$(echo $cfg1 | cut -f2 -d/ -s)
    host=$(echo $cfg2 | cut -f1 -d/)
    db=$(echo $cfg2 | cut -f2 -d/ -s)
    [ -z "$user" ] && return 0
    [ -z "$passwd" ] && return 0
    [ -z "$host" ] && return 0
    [ -z "$db" ] && db=dpm_db
    export PGPASSWORD=$passwd
    psql="psql -t -q -U $user $db"
    vmajor=$($psql -c "select major from schema_version_dpm" 2>/dev/null)
    vminor=$($psql -c "select minor from schema_version_dpm" 2>/dev/null)
    vpatch=$($psql -c "select patch from schema_version_dpm" 2>/dev/null)
    if [ -z "$vmajor" -o -z "$vminor" -o -z "$vpatch" ] ; then
	return 0
    fi
    if [ $vmajor -eq 3 -a $vminor -eq 2 -a $vpatch -eq 0 ] ; then
	$psql <<-EOF
	ALTER TABLE dpm_fs ADD weight INTEGER;
	UPDATE dpm_fs SET weight = 1;
	UPDATE schema_version_dpm SET major = 3, minor = 3, patch = 0;
	EOF
    fi
    return 0
}
getent group dpmmgr > /dev/null || \
    addgroup --quiet --system dpmmgr
getent passwd dpmmgr > /dev/null || \
    adduser --quiet --system --home /var/lib/dpm --shell /bin/sh \
    --ingroup dpmmgr --disabled-password --disabled-login \
    --gecos "DPM manager" dpmmgr
chown dpmmgr:dpmmgr /var/lib/dpm
chown dpmmgr:dpmmgr /var/log/dpm
updatedpm
update-alternatives --install /usr/sbin/dpm dpm \
          /usr/lib/dpm-postgres/dpm 10 \
  --slave /usr/share/man/man8/dpm.8.gz dpm.8.gz \
          /usr/lib/dpm-postgres/dpm.8.gz \
  --slave /usr/share/lcgdm/DPMCONFIG.templ DPMCONFIG.templ \
          /usr/lib/dpm-postgres/DPMCONFIG.templ \
  --slave /etc/init.d/dpm dpm.init \
          /etc/dpm-postgres/dpm.init \
  --slave /etc/default/dpm dpm.conf \
          /etc/dpm-postgres/dpm.conf \
  --slave /etc/logrotate.d/dpm dpm.logrotate \
          /etc/dpm-postgres/dpm.logrotate \
  --slave /usr/sbin/dpm-shutdown dpm-shutdown \
          /usr/lib/dpm-postgres/dpm-shutdown \
  --slave /usr/share/man/man8/dpm-shutdown.8.gz dpm-shutdown.8.gz \
          /usr/lib/dpm-postgres/dpm-shutdown.8.gz \
  --slave /usr/sbin/dpm-buildfsv dpm-buildfsv \
          /usr/lib/dpm-postgres/dpm-buildfsv \
  --slave /usr/share/man/man8/dpm-buildfsv.8.gz dpm-buildfsv.8.gz \
          /usr/lib/dpm-postgres/dpm-buildfsv.8.gz
if [ "$1" = "configure" ] || [ "$1" = "abort-upgrade" ] || [ "$1" = "abort-deconfigure" ] || [ "$1" = "abort-remove" ] ; then
	if [ -x "/etc/init.d/dpm" ]; then
		update-rc.d dpm defaults-disabled >/dev/null
		invoke-rc.d dpm start || exit 1
	fi
fi
 |