在Airflow DAG中的任务中设置retry_exponential_backoff参数为True，以便在失败后自动进行指数级的退避重试。

示例代码如下：

from datetime import datetime, timedelta
from airflow import DAG
from airflow.operators.bash_operator import BashOperator

default_args = {
    'owner': 'airflow',
    'depends_on_past': False,
    'start_date': datetime(2021, 10, 1),
    'retry_delay': timedelta(minutes=5),
    'retry_exponential_backoff': True
}

dag = DAG('example_dag', default_args=default_args, schedule_interval=timedelta(days=1))

task1 = BashOperator(
    task_id='task1',
    bash_command='echo "Hello World!"',
    retries=3,
    dag=dag
)

task2 = BashOperator(
    task_id='task2',
    bash_command='echo "Retry if failed"',
    retries=3,
    dag=dag
)

task1 >> task2