SSM Session Manager connection by tag:key=Name or instance-id. ssmsm is a straight cli session, while ssmsmwin does port forwarding to use RDP via localhost.

ssmsm

#!/usr/bin/env bash
# shellcheck disable=SC2086
ssm_sm(){
  [[ -n $DEBUG ]] && set -x

  ARG1="$1"

  get_name(){
    INSTANCENAME=$(aws ec2 describe-tags \
      --filters \
        Name=resource-id,Values=${INSTANCEID} \
        Name=key,Values=Name \
      --query 'Tags[].Value' \
      --output text)
    }

  get_id(){
    INSTANCENAME=${ARG1}
    INSTANCEID=$(aws ec2 describe-instances \
      --filters \
        Name=tag-value,Values=${INSTANCENAME} \
        Name=instance-state-name,Values=running \
      --query 'Reservations[].Instances[].InstanceId' \
      --out text)
    }

  usage(){ echo "no instance id or name specified in \$1"; exit 1; }

  [[ -z ${ARG1} ]] && usage
  if [[ ${ARG1} = i-* ]];then
    INSTANCEID=${ARG1}
    get_name
  else
    get_id
  fi
  if [[ -z ${INSTANCEID} ]];then
    exit 1; 
  else 
    echo "Target: Instance ${INSTANCEID} (${INSTANCENAME})";
  fi

  aws ssm start-session \
      --target ${INSTANCEID}
  # shellcheck disable=SC2181
  while [[ $? -ne 0 ]]; do
    sleep 1; clear; 
    echo -n "Trying..."; 
    aws ssm start-session \
      --target ${INSTANCEID} 2> /dev/null; done
  echo "Target: Instance ${INSTANCEID} (${INSTANCENAME})"
}
ssm_sm $*

ssmsmwin

#!/usr/bin/env bash
# shellcheck disable=SC2086
ssm_sm_win(){
  [[ -n $DEBUG ]] && set -x

  ARG1="$1"

  get_name(){
    INSTANCENAME=$(aws ec2 describe-tags \
      --filters \
        Name=resource-id,Values=${INSTANCEID} \
        Name=key,Values=Name \
      --query 'Tags[].Value' \
      --output text)
    }

  get_id(){
    INSTANCENAME=${ARG1}
    INSTANCEID=$(aws ec2 describe-instances \
      --filters \
        Name=tag-value,Values=${INSTANCENAME} \
        Name=instance-state-name,Values=running \
      --query 'Reservations[].Instances[].InstanceId' \
      --out text)
    }

  usage(){ echo "no instance id or name specified in \$1"; exit 1; }

  [[ -z ${ARG1} ]] && usage
  if [[ ${ARG1} = i-* ]];then
    INSTANCEID=${ARG1}
    get_name
  else
    get_id
  fi
  [[ -z ${INSTANCEID} ]] && exit 1 || echo "Target: Instance ${INSTANCEID} (${INSTANCENAME})"

  aws ssm start-session \
      --target ${INSTANCEID} \
      --document-name AWS-StartPortForwardingSession \
      --parameters '{"portNumber":["3389"],"localPortNumber":["3389"]}'
  echo "Target: Instance ${INSTANCEID} (${INSTANCENAME})"
}
ssm_sm_win $*