n=0
while :
do
   docker pull $2 \
    && docker tag $2 $1$2 \
    && docker push $1$2 && break  # substitute your command here
   n=$((n+1))
   if [ $n ge 2 ]; then
      echo "initialise failed"
      exit 1
   fi

   echo "retrying..$n"
   sleep 1
done