为什么要选举DR/BDR？选举的原则是？请详细说明
详细请参考https://blog.csdn.net/qq_40934971/article/details/116091465?ops_request_misc=%257B%2522request%255Fid%2522%253A%2522168371246116800213065514%2522%252C%2522scm%2522%253A%252220140713.130102334.pc%255Fall.%2522%257D&request_id=168371246116800213065514&biz_id=0&utm_medium=distribute.pc_search_result.none-task-blog-2~all~first_rank_ecpm_v1~rank_v31_ecpm-2-116091465-null-null.142^v86^insert_down1,239^v2^insert_chatgpt&utm_term=.%E4%B8%BA%E4%BB%80%E4%B9%88%E8%A6%81%E9%80%89%E6%8B%A9DR%E5%92%8CBDR%EF%BC%9F&spm=1018.2226.3001.4187