If you manage several OpenVZ containers, here is a simple bash script to keep the OpenVZ containers upto date.

#!/bin/bash
# vzyum_updates.sh
# updates VEs

VE_LIST=$(/usr/sbin/vzlist -H -o veid | grep -v Warning)

for VE in ${VE_LIST}
do
/usr/bin/vzyum $VE update
done

exit 0