Bash script to add openvpn keys and certs inline

#!/bin/bash
#######################################################################
#       Latest versions of Openvpn supports inline certs and keys
#       so you have one client script, instead of script plus 4 keys and certs
#
#       This tool assumes
#       1) Openvpn script and certs plus keys are in same directory
#       2) Certs are usually specified in Openvpn script like
#          ca capi.crt
#             or
#          ca /etc/local/openvpn/capi.crt
#
#       How to use this script:
#       Save as combine.sh in directory where cert,keys and Openvpn script is.
#       e.g. sudo wget http://pastebin.com/raw.php?i=5u0b8EWF -O $HOME/openvpn-client-files/combine.sh
#       make executable
#       e.g. sudo chmod +x $HOME/openvpn-client-files/combine.sh
#       Run
#       e.g. sudo $HOME/openvpn-client-files/combine.sh
########################################################################
#   Name of certs and keys and client ovpn script
#

ca="capi.crt"
cert="clientpi.crt"
key="clientpi.key"
tlsauth="tapi.key"
ovpndest="raspberry.ovpn"

########################################################################
#   Backup to new subdirectory, just incase
#
mkdir -p backup
cp $ca $cert $key $tlsauth $ovpndest ./backup

########################################################################
#   Delete existing call to keys and certs
#
    sed -i \
    -e '/ca .*'$ca'/d'  \
    -e '/cert .*'$cert'/d' \
    -e '/key .*'$key'/d' \
    -e '/tls-auth .*'$tlsauth'/d' $ovpndest

########################################################################
#   Add keys and certs inline
#
echo "key-direction 1" >> $ovpndest

echo "<ca>" >> $ovpndest
awk /BEGIN/,/END/ < ./$ca >> $ovpndest
echo "</ca>" >> $ovpndest

echo "<cert>" >> $ovpndest
awk /BEGIN/,/END/ < ./$cert >> $ovpndest
echo "</cert>" >> $ovpndest

echo "<key>" >> $ovpndest
awk /BEGIN/,/END/ < ./$key >> $ovpndest
echo "</key>" >> $ovpndest

echo "<tls-auth>" >> $ovpndest
awk /BEGIN/,/END/ < ./$tlsauth >> $ovpndest
echo "</tls-auth>" >> $ovpndest

########################################################################
#   Delete key and cert files, backup already made hopefully
#
rm $ca $cert $key $tlsauth