问题描述
我正在尝试复制仍在运行/正在主动接受来自用户的请求（例如插入和更新）的数据库服务器。
我运行了下面提到的此命令，开始将主服务器复制到复制服务器：
root@replica:~#sudo -u postgres pg_basebackup -h [PRIMARY_IP] -D /var/lib/postgresql/12/main -U replication -P -v
备份过程没有错误并完成了，但是尝试启动postgresql服务器时遇到如下错误。
root@replica:~#tail /var/log/postgresql/postgresql-12-main.log
2020-10-03 01:15:12.198 UTC [552567] FATAL: database system identifier differs between the primary and standby
2020-10-03 01:15:12.198 UTC [552567] DETAIL: The primary's identifier is 6805716485467355646,the standby's identifier is 6875279138564418280.
2020-10-03 01:15:17.204 UTC [552568] FATAL: database system identifier differs between the primary and standby
2020-10-03 01:15:17.204 UTC [552568] DETAIL: The primary's identifier is 6805716485467355646,the standby's identifier is 6875279138564418280.
2020-10-03 01:15:22.207 UTC [552570] FATAL: database system identifier differs between the primary and standby
2020-10-03 01:15:22.207 UTC [552570] DETAIL: The primary's identifier is 6805716485467355646,the standby's identifier is 6875279138564418280.
2020-10-03 01:15:27.212 UTC [552579] FATAL: database system identifier differs between the primary and standby
2020-10-03 01:15:27.212 UTC [552579] DETAIL: The primary's identifier is 6805716485467355646,the standby's identifier is 6875279138564418280.
2020-10-03 01:15:32.216 UTC [552581] FATAL: database system identifier differs between the primary and standby
2020-10-03 01:15:32.216 UTC [552581] DETAIL: The primary's identifier is 6805716485467355646,the standby's identifier is 6875279138564418280.
有人知道如何解决此问题而无需再次尝试pg_basebackup处理吗？因为这花了我很多时间和带宽。
解决方法
是的，我以前从未复制过它。我遵循@jjanes的建议，我删除了以前的副本，然后运行：
sudo -u postgres pg_basebackup -h [PRIMARY_IP] -D /var/lib/postgresql/12/main -U replication -P -v -R -X stream -C -S pgbackup1
及其工作。