Shell Programming and Scripting

arg_inst=`echo $1 | awk '{ print tolower($1) }'`

if   [[ ${arg_inst} == "tstt11" || ${arg_inst} == "tstq11" || ${arg_inst} == "tstp11" ]] then
   echo "- arg_inst = $arg_inst ---> NODE 1"
elif [[ ${arg_inst} == "tstt12" || ${arg_inst} == "tstq12" || ${arg_inst} == "tstp12" ]] then
   echo "- arg_inst = $arg_inst ---> NODE 2"
elif [[ ${arg_inst} == "tstt13" || ${arg_inst} == "tstq13" || ${arg_inst} == "tstp13" ]] then
   echo "- arg_inst = $arg_inst ---> NODE 3"
else
   echo "- arg_inst = $arg_inst is not a valid instance that we required !!!"
fi

if   [[ ${1,,} == tst[tqp]1[123] ]]
  then  echo "- arg_inst = $1 ---> NODE ${1#${1%?}}"
  else  echo "- arg_inst = $1 is not a valid instance that we required !!!"
fi

node_nr=${1#[tT][sS][tT][tTpPqQ]1}
case $node_nr in
  [123])
    echo "- arg_inst = $1 ---> NODE $node_nr"
    ;;
  *)
    echo "- arg_inst = $1 is not a valid instance that we required !!!"
esac

pat=[tT][sS][tT][tTpPqQ]1
case $1 in
  $pat[123])
    echo "- arg_inst = $1 ---> NODE ${1#$pat}"
    ;;
  *)
    echo "- arg_inst = $1 is not a valid instance that we required !!!"
esac