PostgreSQL 高可用集群 patroni 自动故障转移测试

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MSSQL123 · 2026-05-22 · via 博客园 - MSSQL123

网上有很多关于patroni的文章很多，绝大多数文章是通过手动搭建的方式，仅做出了一个patroni的环境搭建，包括各种微信群等，对于patroni参数的使用，故障转移的原理以及实操都只字未提，本文通过Ubuntu 20 环境下 patroni 自动化安装，一分钟快速搭建 patroni 集群来快速搭建一个集群，以及实操的方式实现故障转移的测试和验证，通过模拟真实的故障以及故障转移的日志，来分析故障转移的实现和效果。

2026-05-21 08:46:37,142 INFO: no action. I am (ubuntu11), the leader with the lock
2026-05-21 08:46:47,145 INFO: no action. I am (ubuntu11), the leader with the lock
2026-05-21 08:46:57,190 INFO: no action. I am (ubuntu11), the leader with the lock
2026-05-21 08:47:07,148 INFO: no action. I am (ubuntu11), the leader with the lock
2026-05-21 08:47:17,145 INFO: no action. I am (ubuntu11), the leader with the lock
2026-05-21 08:47:27,189 INFO: no action. I am (ubuntu11), the leader with the lock
2026-05-21 08:47:37,153 INFO: no action. I am (ubuntu11), the leader with the lock

Ubuntu 12 从节点日志

2026-05-21 08:46:47,628 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)
2026-05-21 08:46:57,628 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)
2026-05-21 08:47:07,671 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)
2026-05-21 08:47:17,632 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)
2026-05-21 08:47:27,675 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)
2026-05-21 08:47:37,139 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)
2026-05-21 08:47:47,233 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)
2026-05-21 08:47:57,681 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)

Ubuntu 13 从节点日志

2026-05-21 08:46:57,643 INFO: no action. I am (ubuntu13), a secondary, and following a leader (ubuntu11)
2026-05-21 08:47:07,696 INFO: no action. I am (ubuntu13), a secondary, and following a leader (ubuntu11)
2026-05-21 08:47:17,647 INFO: no action. I am (ubuntu13), a secondary, and following a leader (ubuntu11)
2026-05-21 08:47:27,688 INFO: no action. I am (ubuntu13), a secondary, and following a leader (ubuntu11)
2026-05-21 08:47:37,155 INFO: no action. I am (ubuntu13), a secondary, and following a leader (ubuntu11)
2026-05-21 08:47:47,255 INFO: no action. I am (ubuntu13), a secondary, and following a leader (ubuntu11)
2026-05-21 08:47:57,696 INFO: no action. I am (ubuntu13), a secondary, and following a leader (ubuntu11)

1，自动故障转移场景1：主节点OS正常，patroni服务异常故障

主节点状态正常，关闭主节点patroni服务模拟主节点故障

root@ubuntu11:/usr/local/patroni_install# patronictl -c /usr/local/pgsql17/patroni/patroni.yml list
+ Cluster: pg_cluster_wy_prod (7641831362696373502) ---------+----+-------------+-----+------------+-----+
| Member   | Host                 | Role         | State     | TL | Receive LSN | Lag | Replay LSN | Lag |
+----------+----------------------+--------------+-----------+----+-------------+-----+------------+-----+
| ubuntu11 | 192.168.152.121:9000 | Leader       | running   |  6 |             |     |            |     |
| ubuntu12 | 192.168.152.122:9000 | Sync Standby | streaming |  6 |   0/F000348 |   0 |  0/F000348 |   0 |
| ubuntu13 | 192.168.152.123:9000 | Replica      | streaming |  6 |   0/F000348 |   0 |  0/F000348 |   0 |
+----------+----------------------+--------------+-----------+----+-------------+-----+------------+-----+
root@ubuntu11:/usr/local/patroni_install# systemctl stop patroni
root@ubuntu11:/usr/local/patroni_install#

从节点Ubuntu12上观察到的集群状态，此时原始主节点已处于停止状态

root@ubuntu12:/usr/local/patroni_install# patronictl -c /usr/local/pgsql17/patroni/patroni.yml list
+ Cluster: pg_cluster_wy_prod (7641831362696373502) ---------+----+-------------+-----+------------+-----+
| Member   | Host                 | Role         | State     | TL | Receive LSN | Lag | Replay LSN | Lag |
+----------+----------------------+--------------+-----------+----+-------------+-----+------------+-----+
| ubuntu11 | 192.168.152.121:9000 | Replica      | stopped   |    |     unknown |     |    unknown |     |
| ubuntu12 | 192.168.152.122:9000 | Leader       | running   |  7 |             |     |            |     |
| ubuntu13 | 192.168.152.123:9000 | Sync Standby | streaming |  7 |  0/100001A8 |   0 | 0/100001A8 |   0 |
+----------+----------------------+--------------+-----------+----+-------------+-----+------------+-----+

原始从节点Ubuntu12，成为新的主节点，日志如下

......
2026-05-21 08:55:27,680 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)
2026-05-21 08:55:37,723 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)
2026-05-21 08:55:47,683 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)
2026-05-21 08:55:57,681 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)
2026-05-21 08:56:06,109 WARNING: Request failed to ubuntu11: GET http://192.168.152.121:8008/patroni (HTTPConnectionPool(host='192.168.152.121', port=8008): Max retries exceeded with url: /patroni (Caused by ProtocolError('Connection aborted.', ConnectionResetError(104, 'Connection reset by peer'))))
2026-05-21 08:56:06,169 INFO: promoted self to leader by acquiring session lock
2026-05-21 08:56:06,169 INFO: Lock owner: ubuntu12; I am ubuntu12
2026-05-21 08:56:06,172 INFO: updated leader lock during promote
server promoting
2026-05-21 08:56:07,185 INFO: Lock owner: ubuntu12; I am ubuntu12
2026-05-21 08:56:07,195 INFO: Assigning synchronous standby status to ['ubuntu13']
server signaled
2026-05-21 08:56:09,324 INFO: Synchronous standby status assigned to ['ubuntu13']
2026-05-21 08:56:09,369 INFO: no action. I am (ubuntu12), the leader with the lock
2026-05-21 08:56:17,196 INFO: no action. I am (ubuntu12), the leader with the lock
2026-05-21 08:56:27,187 INFO: no action. I am (ubuntu12), the leader with the lock
2026-05-21 08:56:37,242 INFO: no action. I am (ubuntu12), the leader with the lock
......

这种场景下的故障转移的流程：
手动关闭Ubuntu11 Patroni 主节点模拟故障 ———>Ubuntu 11上的patroni主动删除 DCS 中的 leader key———> Ubuntu12 从节点经过loop_wait轮训后检测到DSC无主 ———> 获取锁提升为 Leader———> promote 本地PostgreSQL为主库

2，自动故障转移场景2：主节点服务器断电

Ubuntu11 通过“关机”（而非关闭客户机）来模拟服务器突然断电，这种场景需要深刻理解租约寿命，也就是ttl（默认 30 秒）参数的概念

新的主节点Ubuntu 12上看到的集群状态

root@ubuntu13:/usr/local/patroni_install# patronictl -c /usr/local/pgsql17/patroni/patroni.yml list
+ Cluster: pg_cluster_wy_prod (7642212398676862997) ----+----+-------------+-----+------------+-----+------------------------+
| Member   | Host                 | Role    | State     | TL | Receive LSN | Lag | Replay LSN | Lag | Tags                   |
+----------+----------------------+---------+-----------+----+-------------+-----+------------+-----+------------------------+
| ubuntu11 | 192.168.152.121:9000 | Leader  | running   | 10 |             |     |            |     | failover_priority: 100 |
| ubuntu12 | 192.168.152.122:9000 | Replica | streaming | 10 |   0/C000000 |   0 |  0/C000358 |   0 | failover_priority: 80  |
| ubuntu13 | 192.168.152.123:9000 | Replica | streaming | 10 |   0/C000380 |   0 |  0/C000380 |   0 | failover_priority: 60  |
+----------+----------------------+---------+-----------+----+-------------+-----+------------+-----+------------------------+
root@ubuntu13:/usr/local/patroni_install#
root@ubuntu13:/usr/local/patroni_install# patronictl -c /usr/local/pgsql17/patroni/patroni.yml list
+ Cluster: pg_cluster_wy_prod (7642212398676862997) ---------+----+-------------+-----+------------+-----+-----------------------+
| Member   | Host                 | Role         | State     | TL | Receive LSN | Lag | Replay LSN | Lag | Tags                  |
+----------+----------------------+--------------+-----------+----+-------------+-----+------------+-----+-----------------------+
| ubuntu12 | 192.168.152.122:9000 | Leader       | running   | 11 |             |     |            |     | failover_priority: 80 |
| ubuntu13 | 192.168.152.123:9000 | Sync Standby | streaming | 11 |   0/C000688 |   0 |  0/C000688 |   0 | failover_priority: 60 |
+----------+----------------------+--------------+-----------+----+-------------+-----+------------+-----+-----------------------+
root@ubuntu13:/usr/local/patroni_install#

新的主节点Ubuntu12上patroni的日志

2026-05-22 13:53:59,956 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)
2026-05-22 13:54:10,451 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)
2026-05-22 13:54:20,026 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)
2026-05-22 13:54:30,458 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)
2026-05-22 13:54:40,461 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)
2026-05-22 13:54:50,499 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)
2026-05-22 13:55:00,456 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)
2026-05-22 13:55:10,457 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)######差不多这个点开始对Ubuntu11掉电
2026-05-22 13:55:20,498 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)######为什么这个点，检测到的Ubuntu11还是正常状态？因为Ubuntu11的lease也就是租约还没有过期
2026-05-22 13:55:32,106 WARNING: Request failed to ubuntu11: GET http://192.168.152.121:8008/patroni (HTTPConnectionPool(host='192.168.152.121', port=8008): Max retries exceeded with url: /patroni (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f893566d880>, 'Connection to 192.168.152.121 timed out. (connect timeout=2)')))
2026-05-22 13:55:32,114 INFO: promoted self to leader by acquiring session lock
2026-05-22 13:55:32,114 INFO: Lock owner: ubuntu12; I am ubuntu12
2026-05-22 13:55:32,115 INFO: updated leader lock during promote
2026-05-22 13:55:33,137 INFO: Lock owner: ubuntu12; I am ubuntu12
2026-05-22 13:55:33,193 INFO: Assigning synchronous standby status to ['ubuntu13']
2026-05-22 13:55:35,316 INFO: Synchronous standby status assigned to ['ubuntu13']
2026-05-22 13:55:35,322 INFO: no action. I am (ubuntu12), the leader with the lock
2026-05-22 13:55:35,377 INFO: no action. I am (ubuntu12), the leader with the lock
2026-05-22 13:55:45,324 INFO: no action. I am (ubuntu12), the leader with the lock
2026-05-22 13:55:55,367 INFO: no action. I am (ubuntu12), the leader with the lock
2026-05-22 13:56:05,329 INFO: no action. I am (ubuntu12), the leader with the lock

新的主节点通过psql查看身份状态

postgres=#
postgres=#
postgres=# select now(),pg_is_in_recovery();            ###########################这里开始对原始主节点Ubuntu11 掉电，然后连续查询
              now              | pg_is_in_recovery
-------------------------------+-------------------
 2026-05-22 13:55:10.849473+08 | t
(1 row)

postgres=# select now(),pg_is_in_recovery();
              now              | pg_is_in_recovery
-------------------------------+-------------------
 2026-05-22 13:55:11.665724+08 | t
(1 row)

postgres=# select now(),pg_is_in_recovery();
             now              | pg_is_in_recovery
------------------------------+-------------------
 2026-05-22 13:55:12.32947+08 | t
(1 row)

postgres=# select now(),pg_is_in_recovery();
              now              | pg_is_in_recovery
-------------------------------+-------------------
 2026-05-22 13:55:13.017149+08 | t
(1 row)

postgres=# select now(),pg_is_in_recovery();
              now              | pg_is_in_recovery
-------------------------------+-------------------
 2026-05-22 13:55:13.799962+08 | t
(1 row)

postgres=# select now(),pg_is_in_recovery();
              now              | pg_is_in_recovery
-------------------------------+-------------------
 2026-05-22 13:55:14.902866+08 | t
(1 row)

postgres=# select now(),pg_is_in_recovery();
              now              | pg_is_in_recovery
-------------------------------+-------------------
 2026-05-22 13:55:15.672331+08 | t
(1 row)

postgres=# select now(),pg_is_in_recovery();
              now              | pg_is_in_recovery
-------------------------------+-------------------
 2026-05-22 13:55:16.435662+08 | t
(1 row)

postgres=# select now(),pg_is_in_recovery();
              now              | pg_is_in_recovery
-------------------------------+-------------------
 2026-05-22 13:55:17.070935+08 | t
(1 row)

postgres=# select now(),pg_is_in_recovery();
              now              | pg_is_in_recovery
-------------------------------+-------------------
 2026-05-22 13:55:17.816528+08 | t
(1 row)

postgres=# select now(),pg_is_in_recovery();
              now              | pg_is_in_recovery
-------------------------------+-------------------
 2026-05-22 13:55:18.546785+08 | t
(1 row)

postgres=# select now(),pg_is_in_recovery();
              now              | pg_is_in_recovery
-------------------------------+-------------------
 2026-05-22 13:55:19.393943+08 | t
(1 row)

#......中间省略掉......

postgres=# select now(),pg_is_in_recovery();
              now              | pg_is_in_recovery
-------------------------------+-------------------
 2026-05-22 13:55:29.759037+08 | t
(1 row)

postgres=# select now(),pg_is_in_recovery();
              now              | pg_is_in_recovery
-------------------------------+-------------------
 2026-05-22 13:55:30.417626+08 | t
(1 row)

postgres=# select now(),pg_is_in_recovery();
              now              | pg_is_in_recovery
-------------------------------+-------------------
 2026-05-22 13:55:31.089604+08 | t
(1 row)

postgres=# select now(),pg_is_in_recovery();
              now              | pg_is_in_recovery
-------------------------------+-------------------
 2026-05-22 13:55:31.775459+08 | t
(1 row)

postgres=# select now(),pg_is_in_recovery();            ###########################22秒之后，新的主节点才真正promote起来
              now              | pg_is_in_recovery
-------------------------------+-------------------
 2026-05-22 13:55:32.400935+08 | f
(1 row)

postgres=# select now(),pg_is_in_recovery();
             now              | pg_is_in_recovery
------------------------------+-------------------
 2026-05-22 13:55:33.27183+08 | f
(1 row)

postgres=# select now(),pg_is_in_recovery();
              now              | pg_is_in_recovery
-------------------------------+-------------------
 2026-05-22 13:55:33.950342+08 | f
(1 row)

postgres=# select now(),pg_is_in_recovery();
              now              | pg_is_in_recovery
-------------------------------+-------------------
 2026-05-22 13:55:34.758651+08 | f
(1 row)

postgres=# postgres=#
postgres-# postgres=#

结合上述日志，来理解ttl的概念，从时间的维度来观察：

1，2026-05-22 13:55:10,457，上面提到差不多在这个是时间点开始对原主节点Ubuntu11断电，
2，2026-05-22 13:55:20,498 ，patroni日志中检测到的Ubuntu11还是正常状态？
3， 2026-05-22 13:55:32.400935，通过查询新的主节点的pg_is_in_recovery，发现pg_is_in_recovery才变为f，也即故障转移成功

日志是否与实际操作的不符合，明明Ubuntu11在13:55:10就断电了，为什么13:55:20还在检测的时候还是正常的，但是直到13:55:32，新的主节点才真正开始工作，这是不是矛盾的？

这是因为，在13:55:10断电，在13:55:10前几秒（减去一个loop_wait的时间点，loop_wait默认10秒）， Ubuntu11上的patroni对etcd中的leader key续约，续约一次生效时间为向后推30秒，lease也就是租约还没有过期，其租约大概在13:55:30之后才过期，因此在13:55:20这个时间点，接替它的从节点上的patroni服务，检测到leader key 并没有过期。
直到下一个检测周期，也即13:55:30的时候，这一轮检查的时候才发现“2026-05-22 13:55:32,106 WARNING: Request failed to ubuntu11: GET http://192.168.152.121:8008/patroni (HTTPConnectionPool(host='192.168.152.121', port=8008): Max retries exceeded with url: /patroni (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f893566d880>, 'Connection to 192.168.152.121 timed out. (connect timeout=2)')))”原始主节点异常，为什么日志是13:55:32，在13:55:30的基础上加了2秒呢？因为connect timeout=2

以上才是patroni参数中ttl的真正含义。

这种场景下的故障转移的流程：
关闭Ubuntu11 电源模拟主节点故障 ———>10秒后 Ubuntu 11上的leader 租约扔有效（实际上此时Ubuntu已宕机） ———>10秒后 Ubuntu 11上的leader 租约扔有效（实际上此时Ubuntu已宕机） ———>10秒后 Ubuntu 12检测到leader 失效———> 抢占leader key，promote 本地PostgreSQL为主库

因此如果想提到patroni的故障转移的灵敏性，需要减小ttl的值，也即减少leader key的租约时间，同时也要减小loop_wait，增加判断leader key的频率，来提升故障检测以及转移的灵敏性，但也要意识到，调小这两个参数，可能在网络抖动是会带来的预期之外的故障转移。

3，自动故障转移场景3：主节点网络分区

用iptables -A OUTPUT -d 192.168.152.121 -j DROP

从节点1

root@ubuntu12:/usr/local/patroni_install# sudo iptables -A OUTPUT -d 192.168.152.121 -j DROP
root@ubuntu12:/usr/local/patroni_install# sudo iptables -A INPUT  -s 192.168.152.121 -j DROP
root@ubuntu12:/usr/local/patroni_install#

从节点2

root@ubuntu13:/usr/local/patroni_install# sudo iptables -A OUTPUT -d 192.168.152.121 -j DROP
root@ubuntu13:/usr/local/patroni_install# sudo iptables -A INPUT  -s 192.168.152.121 -j DROP
root@ubuntu13:/usr/local/patroni_install#

网络分区已形成

1，对于新的主节点：Ubuntu12已经成功接管主节点

2026-05-22 14:47:38,980 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)
2026-05-22 14:47:49,402 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)
2026-05-22 14:47:58,941 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)
2026-05-22 14:48:09,491 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)
2026-05-22 14:48:19,441 INFO: no action. I am (ubuntu12), a secondary, and following a leader (ubuntu11)
2026-05-22 14:48:31,104 WARNING: Request failed to ubuntu11: GET http://192.168.152.121:8008/patroni (HTTPConnectionPool(host='192.168.152.121', port=8008): Max retries exceeded with url: /patroni (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f8988fdb1f0>, 'Connection to 192.168.152.121 timed out. (connect timeout=2)')))
2026-05-22 14:48:31,183 INFO: promoted self to leader by acquiring session lock
2026-05-22 14:48:31,187 INFO: Lock owner: ubuntu12; I am ubuntu12
2026-05-22 14:48:31,239 INFO: updated leader lock during promote
2026-05-22 14:48:32,206 INFO: Lock owner: ubuntu12; I am ubuntu12
2026-05-22 14:48:32,214 INFO: Assigning synchronous standby status to ['ubuntu13']
2026-05-22 14:48:34,337 INFO: Synchronous standby status assigned to ['ubuntu13']
2026-05-22 14:48:34,385 INFO: no action. I am (ubuntu12), the leader with the lock
2026-05-22 14:48:42,245 INFO: no action. I am (ubuntu12), the leader with the lock
2026-05-22 14:48:52,256 INFO: no action. I am (ubuntu12), the leader with the lock

需要说明的是，对网络分区的故障转移，与上面主节点断电一样，虽然在新主节点的日志中，从发现到故障转移只用了10秒多，但实际上，在网络分区之后，因为原主节点对于leader key的最后一次续约加上了30秒（ttl），导致网络分区发生后，新的主节点在探测ttl的时候，前2次探测的时候实际上网络分区已经形成，但此时新的主节点尚未接管，直至原主节点的leader key 租约超期，这一点与上面一种情况一样，详细测试过不在赘述。

2，对于原主节点：
此时原主节点日志已无法连接至Ubuntu12 和Ubuntu 13，注意日志
2026-05-22 14:48:17,257 ERROR: Error communicating with DCS
2026-05-22 14:48:17,258 INFO: demoting self because DCS is not accessible and I was a leader
2026-05-22 14:48:17,258 INFO: Demoting self (offline)
原始主节点网络分区之后，自动降级为只读状态，因此不会出现双主或者脑裂的现象。同时会连续不停地尝试连接到Ubuntu12和ubuntu13上的etcd集群（日志在持续生成，没有贴全），以确保网络恢复后自动加入集群

2026-05-22 14:47:38,896 INFO: no action. I am (ubuntu11), the leader with the lock
2026-05-22 14:47:38,963 INFO: no action. I am (ubuntu11), the leader with the lock
2026-05-22 14:47:48,912 INFO: no action. I am (ubuntu11), the leader with the lock
2026-05-22 14:47:58,948 INFO: no action. I am (ubuntu11), the leader with the lock
2026-05-22 14:48:08,903 INFO: Lock owner: ubuntu11; I am ubuntu11
2026-05-22 14:48:12,244 ERROR: Request to server http://192.168.152.121:2379 failed: ReadTimeoutError("HTTPConnectionPool(host='192.168.152.121', port=2379): Read timed out. (read timeout=3.3332171243333355)")
2026-05-22 14:48:12,244 INFO: Reconnection allowed, looking for another server.
2026-05-22 14:48:12,244 INFO: Retrying on http://192.168.152.123:2379
2026-05-22 14:48:13,913 ERROR: Request to server http://192.168.152.123:2379 failed: MaxRetryError("HTTPConnectionPool(host='192.168.152.123', port=2379): Max retries exceeded with url: /v3/lease/keepalive (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f205c04b2b0>, 'Connection to 192.168.152.123 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 14:48:13,913 INFO: Reconnection allowed, looking for another server.
2026-05-22 14:48:13,913 INFO: Retrying on http://192.168.152.122:2379
2026-05-22 14:48:15,583 ERROR: Request to server http://192.168.152.122:2379 failed: MaxRetryError("HTTPConnectionPool(host='192.168.152.122', port=2379): Max retries exceeded with url: /v3/lease/keepalive (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f205c04b2e0>, 'Connection to 192.168.152.122 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 14:48:15,583 INFO: Reconnection allowed, looking for another server.
2026-05-22 14:48:17,253 ERROR: Failed to get list of machines from http://192.168.152.122:2379/v3: MaxRetryError("HTTPConnectionPool(host='192.168.152.122', port=2379): Max retries exceeded with url: /v3/cluster/member/list (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f205c04b520>, 'Connection to 192.168.152.122 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 14:48:17,256 ERROR: watchprefix failed: ProtocolError('Connection broken: IncompleteRead(0 bytes read)', IncompleteRead(0 bytes read))
2026-05-22 14:48:17,257 ERROR: Error communicating with DCS
2026-05-22 14:48:17,258 INFO: demoting self because DCS is not accessible and I was a leader
2026-05-22 14:48:17,258 INFO: Demoting self (offline)
2026-05-22 14:48:18,932 ERROR: Failed to get list of machines from http://192.168.152.122:2379/v3: MaxRetryError("HTTPConnectionPool(host='192.168.152.122', port=2379): Max retries exceeded with url: /v3/cluster/member/list (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f205c04b970>, 'Connection to 192.168.152.122 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 14:49:00,355 INFO: postmaster pid=3525
2026-05-22 14:49:01,400 INFO: demoted self because DCS is not accessible and I was a leader
2026-05-22 14:49:01,403 WARNING: Loop time exceeded, rescheduling immediately.
2026-05-22 14:49:01,405 INFO: Lock owner: ubuntu11; I am ubuntu11
2026-05-22 14:49:01,405 INFO: establishing a new patroni heartbeat connection to postgres
2026-05-22 14:49:04,749 ERROR: Request to server http://192.168.152.121:2379 failed: ReadTimeoutError("HTTPConnectionPool(host='192.168.152.121', port=2379): Read timed out. (read timeout=3.33254870033331)")
2026-05-22 14:49:04,749 INFO: Reconnection allowed, looking for another server.
2026-05-22 14:49:04,749 INFO: Retrying on http://192.168.152.123:2379
2026-05-22 14:49:06,419 ERROR: Request to server http://192.168.152.123:2379 failed: MaxRetryError("HTTPConnectionPool(host='192.168.152.123', port=2379): Max retries exceeded with url: /v3/lease/keepalive (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f205c04bfa0>, 'Connection to 192.168.152.123 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 14:49:06,419 INFO: Reconnection allowed, looking for another server.
2026-05-22 14:49:06,419 INFO: Retrying on http://192.168.152.122:2379
2026-05-22 14:49:08,089 ERROR: Request to server http://192.168.152.122:2379 failed: MaxRetryError("HTTPConnectionPool(host='192.168.152.122', port=2379): Max retries exceeded with url: /v3/lease/keepalive (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f2027e451c0>, 'Connection to 192.168.152.122 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 14:49:08,089 INFO: Reconnection allowed, looking for another server.
2026-05-22 14:49:09,758 ERROR: Failed to get list of machines from http://192.168.152.122:2379/v3: MaxRetryError("HTTPConnectionPool(host='192.168.152.122', port=2379): Max retries exceeded with url: /v3/cluster/member/list (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f205c53fa90>, 'Connection to 192.168.152.122 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 14:49:11,417 ERROR: Request to server http://192.168.152.121:2379 failed: ReadTimeoutError("HTTPConnectionPool(host='192.168.152.121', port=2379): Read timed out. (read timeout=1.00350682653891)")
2026-05-22 14:49:11,417 INFO: Reconnection allowed, looking for another server.
2026-05-22 14:49:13,086 ERROR: Failed to get list of machines from http://192.168.152.122:2379/v3: MaxRetryError("HTTPConnectionPool(host='192.168.152.122', port=2379): Max retries exceeded with url: /v3/cluster/member/list (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f205c04ba60>, 'Connection to 192.168.152.122 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 14:49:13,088 ERROR: Error communicating with DCS
2026-05-22 14:49:13,088 INFO: DCS is not accessible
2026-05-22 14:49:13,088 ERROR: watchprefix failed: ProtocolError('Connection broken: IncompleteRead(0 bytes read)', IncompleteRead(0 bytes read))
2026-05-22 14:49:13,090 WARNING: Loop time exceeded, rescheduling immediately.
2026-05-22 14:49:14,757 ERROR: Failed to get list of machines from http://192.168.152.122:2379/v3: MaxRetryError("HTTPConnectionPool(host='192.168.152.122', port=2379): Max retries exceeded with url: /v3/cluster/member/list (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f205c04b820>, 'Connection to 192.168.152.122 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 14:49:14,763 INFO: Lock owner: ubuntu11; I am ubuntu11
2026-05-22 14:49:18,103 ERROR: Request to server http://192.168.152.121:2379 failed: ReadTimeoutError("HTTPConnectionPool(host='192.168.152.121', port=2379): Read timed out. (read timeout=3.3331819403333234)")
2026-05-22 14:49:18,103 INFO: Reconnection allowed, looking for another server.
2026-05-22 14:49:18,103 INFO: Retrying on http://192.168.152.122:2379
2026-05-22 14:49:19,773 ERROR: Request to server http://192.168.152.122:2379 failed: MaxRetryError("HTTPConnectionPool(host='192.168.152.122', port=2379): Max retries exceeded with url: /v3/lease/keepalive (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f2027e450d0>, 'Connection to 192.168.152.122 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 14:49:19,773 INFO: Reconnection allowed, looking for another server.
2026-05-22 14:49:19,773 INFO: Retrying on http://192.168.152.123:2379
2026-05-22 14:49:21,441 ERROR: Request to server http://192.168.152.123:2379 failed: MaxRetryError("HTTPConnectionPool(host='192.168.152.123', port=2379): Max retries exceeded with url: /v3/lease/keepalive (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f2027e45370>, 'Connection to 192.168.152.123 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 14:49:21,442 INFO: Reconnection allowed, looking for another server.
2026-05-22 14:49:23,112 ERROR: Failed to get list of machines from http://192.168.152.122:2379/v3: MaxRetryError("HTTPConnectionPool(host='192.168.152.122', port=2379): Max retries exceeded with url: /v3/cluster/member/list (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f2027e45670>, 'Connection to 192.168.152.122 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 14:49:23,114 ERROR: Error communicating with DCS
2026-05-22 14:49:23,114 INFO: DCS is not accessible
2026-05-22 14:49:23,114 ERROR: watchprefix failed: ProtocolError('Connection broken: IncompleteRead(0 bytes read)', IncompleteRead(0 bytes read))
2026-05-22 14:49:23,115 WARNING: Loop time exceeded, rescheduling immediately.
2026-05-22 14:49:24,784 ERROR: Failed to get list of machines from http://192.168.152.122:2379/v3: MaxRetryError("HTTPConnectionPool(host='192.168.152.122', port=2379): Max retries exceeded with url: /v3/cluster/member/list (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f2027e45b50>, 'Connection to 192.168.152.122 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 14:49:24,790 INFO: Lock owner: ubuntu11; I am ubuntu11
2026-05-22 14:49:28,128 ERROR: Request to server http://192.168.152.121:2379 failed: ReadTimeoutError("HTTPConnectionPool(host='192.168.152.121', port=2379): Read timed out. (read timeout=3.332673626333379)")
2026-05-22 14:49:28,128 INFO: Reconnection allowed, looking for another server.
2026-05-22 14:49:28,128 INFO: Retrying on http://192.168.152.123:2379
2026-05-22 14:49:29,799 ERROR: Request to server http://192.168.152.123:2379 failed: MaxRetryError("HTTPConnectionPool(host='192.168.152.123', port=2379): Max retries exceeded with url: /v3/lease/keepalive (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f2027e5c220>, 'Connection to 192.168.152.123 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 14:49:29,799 INFO: Reconnection allowed, looking for another server.
2026-05-22 14:49:29,799 INFO: Retrying on http://192.168.152.122:2379
2026-05-22 14:49:31,469 ERROR: Request to server http://192.168.152.122:2379 failed: MaxRetryError("HTTPConnectionPool(host='192.168.152.122', port=2379): Max retries exceeded with url: /v3/lease/keepalive (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f205c41f460>, 'Connection to 192.168.152.122 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 14:49:31,469 INFO: Reconnection allowed, looking for another server.
2026-05-22 14:49:33,138 ERROR: Failed to get list of machines from http://192.168.152.122:2379/v3: MaxRetryError("HTTPConnectionPool(host='192.168.152.122', port=2379): Max retries exceeded with url: /v3/cluster/member/list (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f205c53f9a0>, 'Connection to 192.168.152.122 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 14:49:34,794 ERROR: Request to server http://192.168.152.121:2379 failed: ReadTimeoutError("HTTPConnectionPool(host='192.168.152.121', port=2379): Read timed out. (read timeout=1.1904628130222932)")
2026-05-22 14:49:34,794 INFO: Reconnection allowed, looking for another server.
2026-05-22 14:49:36,464 ERROR: Failed to get list of machines from http://192.168.152.122:2379/v3: MaxRetryError("HTTPConnectionPool(host='192.168.152.122', port=2379): Max retries exceeded with url: /v3/cluster/member/list (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f205c04b0a0>, 'Connection to 192.168.152.122 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 14:49:36,468 ERROR: watchprefix failed: ProtocolError('Connection broken: IncompleteRead(0 bytes read)', IncompleteRead(0 bytes read))
2026-05-22 14:49:36,468 ERROR: Error communicating with DCS
2026-05-22 14:49:36,468 INFO: DCS is not accessible
2026-05-22 14:49:36,470 WARNING: Loop time exceeded, rescheduling immediately.
2026-05-22 14:49:38,140 ERROR: Failed to get list of machines from http://192.168.152.122:2379/v3: MaxRetryError("HTTPConnectionPool(host='192.168.152.122', port=2379): Max retries exceeded with url: /v3/cluster/member/list (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f205c04b8b0>, 'Connection to 192.168.152.122 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 14:49:38,145 INFO: Lock owner: ubuntu11; I am ubuntu11
2026-05-22 14:49:41,485 ERROR: Request to server http://192.168.152.121:2379 failed: ReadTimeoutError("HTTPConnectionPool(host='192.168.152.121', port=2379): Read timed out. (read timeout=3.33319548833335)")
2026-05-22 14:49:41,485 INFO: Reconnection allowed, looking for another server.
2026-05-22 14:49:41,485 INFO: Retrying on http://192.168.152.122:2379
2026-05-22 14:49:43,153 ERROR: Request to server http://192.168.152.122:2379 failed: MaxRetryError("HTTPConnectionPool(host='192.168.152.122', port=2379): Max retries exceeded with url: /v3/lease/keepalive (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f2027e45fa0>, 'Connection to 192.168.152.122 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 14:49:43,153 INFO: Reconnection allowed, looking for another server.
2026-05-22 14:49:43,153 INFO: Retrying on http://192.168.152.123:2379
2026-05-22 14:49:44,823 ERROR: Request to server http://192.168.152.123:2379 failed: MaxRetryError("HTTPConnectionPool(host='192.168.152.123', port=2379): Max retries exceeded with url: /v3/lease/keepalive (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f2027e459d0>, 'Connection to 192.168.152.123 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 14:49:44,823 INFO: Reconnection allowed, looking for another server.
2026-05-22 14:49:46,493 ERROR: Failed to get list of machines from http://192.168.152.122:2379/v3: MaxRetryError("HTTPConnectionPool(host='192.168.152.122', port=2379): Max retries exceeded with url: /v3/cluster/member/list (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f2027e45ac0>, 'Connection to 192.168.152.122 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 14:49:48,150 ERROR: Request to server http://192.168.152.121:2379 failed: ReadTimeoutError("HTTPConnectionPool(host='192.168.152.121', port=2379): Read timed out. (read timeout=1.4432267216546961)")
2026-05-22 14:49:48,150 INFO: Reconnection allowed, looking for another server.
2026-05-22 14:49:49,819 ERROR: Failed to get list of machines from http://192.168.152.122:2379/v3: MaxRetryError("HTTPConnectionPool(host='192.168.152.122', port=2379): Max retries exceeded with url: /v3/cluster/member/list (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f2027e45100>, 'Connection to 192.168.152.122 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 14:49:49,821 ERROR: Error communicating with DCS
2026-05-22 14:49:49,821 ERROR: watchprefix failed: ProtocolError('Connection broken: IncompleteRead(0 bytes read)', IncompleteRead(0 bytes read))
2026-05-22 14:49:49,821 INFO: DCS is not accessible

Ubuntu 12解除网络分区，

root@ubuntu12:/usr/local/patroni_install# sudo iptables -D OUTPUT -d 192.168.152.121 -j DROP
root@ubuntu12:/usr/local/patroni_install# sudo iptables -D INPUT  -s 192.168.152.121 -j DROP

Ubuntu 13上也解除网络分区

root@ubuntu13:/usr/local/patroni_install# sudo iptables -D OUTPUT -d 192.168.152.121 -j DROP
root@ubuntu13:/usr/local/patroni_install# sudo iptables -D INPUT  -s 192.168.152.121 -j DROP
root@ubuntu13:/usr/local/patroni_install#
root@ubuntu13:/usr/local/patroni_install#

可以发现被隔离的Ubuntu11自动以从节点身份加入集群。

root@ubuntu12:/usr/local/patroni_install#
root@ubuntu12:/usr/local/patroni_install#
root@ubuntu12:/usr/local/patroni_install# patronictl -c /usr/local/pgsql17/patroni/patroni.yml list
+ Cluster: pg_cluster_wy_prod (7642589780522937440) ---------+----+-------------+-----+------------+-----+
| Member   | Host                 | Role         | State     | TL | Receive LSN | Lag | Replay LSN | Lag |
+----------+----------------------+--------------+-----------+----+-------------+-----+------------+-----+
| ubuntu11 | 192.168.152.121:9000 | Replica      | streaming |  5 |   0/60043F0 |   0 |  0/60043F0 |   0 |
| ubuntu12 | 192.168.152.122:9000 | Leader       | running   |  5 |             |     |            |     |
| ubuntu13 | 192.168.152.123:9000 | Sync Standby | streaming |  5 |   0/60043F0 |   0 |  0/60043F0 |   0 |
+----------+----------------------+--------------+-----------+----+-------------+-----+------------+-----+
root@ubuntu12:/usr/local/patroni_install#
root@ubuntu12:/usr/local/patroni_install#

Ubuntu11上的日志，自动执行pg_rewind，然后以从节点的身份加入集群

2026-05-22 15:02:40,971 ERROR: Failed to get list of machines from http://192.168.152.122:2379/v3: MaxRetryError("HTTPConnectionPool(host='192.168.152.122', port=2379): Max retries exceeded with url: /v3/cluster/member/list (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f2027e5c4c0>, 'Connection to 192.168.152.122 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 15:02:42,626 ERROR: Request to server http://192.168.152.121:2379 failed: ReadTimeoutError("HTTPConnectionPool(host='192.168.152.121', port=2379): Read timed out. (read timeout=1.3500901345867078)")
2026-05-22 15:02:42,626 INFO: Reconnection allowed, looking for another server.
2026-05-22 15:02:44,295 ERROR: Failed to get list of machines from http://192.168.152.122:2379/v3: MaxRetryError("HTTPConnectionPool(host='192.168.152.122', port=2379): Max retries exceeded with url: /v3/cluster/member/list (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f2027e5cb80>, 'Connection to 192.168.152.122 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 15:02:44,296 ERROR: Error communicating with DCS
2026-05-22 15:02:44,297 ERROR: watchprefix failed: ProtocolError('Connection broken: IncompleteRead(0 bytes read)', IncompleteRead(0 bytes read))
2026-05-22 15:02:44,297 INFO: DCS is not accessible
2026-05-22 15:02:44,298 WARNING: Loop time exceeded, rescheduling immediately.
2026-05-22 15:02:45,967 ERROR: Failed to get list of machines from http://192.168.152.122:2379/v3: MaxRetryError("HTTPConnectionPool(host='192.168.152.122', port=2379): Max retries exceeded with url: /v3/cluster/member/list (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7f205c04b3a0>, 'Connection to 192.168.152.122 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 15:02:45,975 INFO: Lock owner: ubuntu11; I am ubuntu11
2026-05-22 15:02:47,985 ERROR: failed to update leader lock
2026-05-22 15:02:47,994 INFO: not promoting because failed to update leader lock in DCS
2026-05-22 15:02:47,994 INFO: Lock owner: ubuntu12; I am ubuntu11
2026-05-22 15:02:48,001 INFO: Local timeline=4 lsn=0/70000A0
2026-05-22 15:02:48,027 INFO: primary_timeline=5
2026-05-22 15:02:48,030 INFO: primary: history=1	0/504F580	no recovery target specified
2	0/6003D20	no recovery target specified
3	0/6003EC0	no recovery target specified
4	0/6004148	no recovery target specified
2026-05-22 15:02:48,049 INFO: running pg_rewind from ubuntu12
2026-05-22 15:02:49,312 INFO: running pg_rewind from dbname=postgres user=rewind_user host=192.168.152.122 port=9000 target_session_attrs=read-write
2026-05-22 15:02:50,305 INFO: pg_rewind exit code=0
2026-05-22 15:02:50,305 INFO:  stdout=
2026-05-22 15:02:50,305 INFO:  stderr=pg_rewind: servers diverged at WAL location 0/6004148 on timeline 4
pg_rewind: rewinding from last common checkpoint at 0/6004038 on timeline 4
pg_rewind: Done!

2026-05-22 15:02:50,307 WARNING: Postgresql is not running.
2026-05-22 15:02:50,308 INFO: Lock owner: ubuntu12; I am ubuntu11
2026-05-22 15:02:50,319 INFO: pg_controldata:
  pg_control version number: 1700
  Catalog version number: 202406281
  Database system identifier: 7642589780522937440
  Database cluster state: in archive recovery
  pg_control last modified: Fri May 22 15:02:50 2026
  Latest checkpoint location: 0/6004340
  Latest checkpoint's REDO location: 0/60042E8
  Latest checkpoint's REDO WAL file: 000000050000000000000006
  Latest checkpoint's TimeLineID: 5
  Latest checkpoint's PrevTimeLineID: 5
  Latest checkpoint's full_page_writes: on
  Latest checkpoint's NextXID: 0:762
  Latest checkpoint's NextOID: 24576
  Latest checkpoint's NextMultiXactId: 1
  Latest checkpoint's NextMultiOffset: 0
  Latest checkpoint's oldestXID: 731
  Latest checkpoint's oldestXID's DB: 1
  Latest checkpoint's oldestActiveXID: 762
  Latest checkpoint's oldestMultiXid: 1
  Latest checkpoint's oldestMulti's DB: 1
  Latest checkpoint's oldestCommitTsXid: 0
  Latest checkpoint's newestCommitTsXid: 0
  Time of latest checkpoint: Fri May 22 14:53:31 2026
  Fake LSN counter for unlogged rels: 0/3E8
  Minimum recovery ending location: 0/60043F0
  Min recovery ending loc's timeline: 5
  Backup start location: 0/0
  Backup end location: 0/0
  End-of-backup record required: no
  wal_level setting: replica
  wal_log_hints setting: on
  max_connections setting: 100
  max_worker_processes setting: 8
  max_wal_senders setting: 10
  max_prepared_xacts setting: 0
  max_locks_per_xact setting: 64
  track_commit_timestamp setting: off
  Maximum data alignment: 8
  Database block size: 8192
  Blocks per segment of large relation: 131072
  WAL block size: 8192
  Bytes per WAL segment: 16777216
  Maximum length of identifiers: 64
  Maximum columns in an index: 32
  Maximum size of a TOAST chunk: 1996
  Size of a large-object chunk: 2048
  Date/time type storage: 64-bit integers
  Float8 argument passing: by value
  Data page checksum version: 1
  Mock authentication nonce: 3587dd0ff212f7ed05a16aa24aa1d6a6f187f55d5d6a2e158ce45327a7e55005

2026-05-22 15:02:50,320 INFO: Lock owner: ubuntu12; I am ubuntu11
2026-05-22 15:02:50,367 INFO: starting as a secondary
2026-05-22 15:02:50,368 INFO: closed patroni connections to postgres
2026-05-22 15:02:50,738 INFO: postmaster pid=3952
2026-05-22 15:02:51,774 INFO: Lock owner: ubuntu12; I am ubuntu11
2026-05-22 15:02:51,774 INFO: establishing a new patroni heartbeat connection to postgres
2026-05-22 15:02:51,795 INFO: Local timeline=5 lsn=0/60043F0
2026-05-22 15:02:51,803 INFO: primary_timeline=5
2026-05-22 15:02:51,812 INFO: no action. I am (ubuntu11), a secondary, and following a leader (ubuntu12)
2026-05-22 15:02:52,281 INFO: no action. I am (ubuntu11), a secondary, and following a leader (ubuntu12)
2026-05-22 15:03:02,819 INFO: no action. I am (ubuntu11), a secondary, and following a leader (ubuntu12)
2026-05-22 15:03:12,778 INFO: no action. I am (ubuntu11), a secondary, and following a leader (ubuntu12)
2026-05-22 15:03:22,777 INFO: no action. I am (ubuntu11), a secondary, and following a leader (ubuntu12)

4，自动故障转移场景4：暴力删除主节点PostgreSQL数据文件

这种情况实际情况中几乎不会发生，除非刻意为之，那么直接暴力删除运行中的主节点的PostgreSQL的数据文件会发生什么？

以下是实测，可以发现，暴力删除数据文件之后：1，patroni集群会自动故障转移（因为主节点无法对外提供服务了），2，原主节点会自动从集群中克隆一份数据作为从节点运行

######当前集群正常状态
root@ubuntu11:~# patronictl -c /usr/local/pgsql17/patroni/patroni.yml list
+ Cluster: pg_cluster_wy_prod (7642589780522937440) ---------+----+-------------+-----+------------+-----+
| Member   | Host                 | Role         | State     | TL | Receive LSN | Lag | Replay LSN | Lag |
+----------+----------------------+--------------+-----------+----+-------------+-----+------------+-----+
| ubuntu11 | 192.168.152.121:9000 | Sync Standby | streaming |  6 |   0/70002D0 |   0 |  0/70002D0 |   0 |
| ubuntu12 | 192.168.152.122:9000 | Replica      | streaming |  6 |   0/70002D0 |   0 |  0/70002D0 |   0 |
| ubuntu13 | 192.168.152.123:9000 | Leader       | running   |  6 |             |     |            |     |
+----------+----------------------+--------------+-----------+----+-------------+-----+------------+-----+
root@ubuntu11:~#
root@ubuntu11:~#
root@ubuntu11:~#
root@ubuntu11:~#
######暴力删除原主节点数据文件
root@ubuntu11:~# patronictl -c /usr/local/pgsql17/patroni/patroni.yml list
+ Cluster: pg_cluster_wy_prod (7642589780522937440) ----------------+----+-------------+-----+------------+-----+
| Member   | Host                 | Role         | State            | TL | Receive LSN | Lag | Replay LSN | Lag |
+----------+----------------------+--------------+------------------+----+-------------+-----+------------+-----+
| ubuntu11 | 192.168.152.121:9000 | Leader       | running          |  7 |             |     |            |     |
| ubuntu12 | 192.168.152.122:9000 | Sync Standby | streaming        |  7 |   0/7000410 |   0 |  0/7000410 |   0 |
| ubuntu13 | 192.168.152.123:9000 | Replica      | creating replica |    |     unknown |     |    unknown |     |
+----------+----------------------+--------------+------------------+----+-------------+-----+------------+-----+
root@ubuntu11:~#
######集群恢复正常
root@ubuntu11:~# patronictl -c /usr/local/pgsql17/patroni/patroni.yml list
+ Cluster: pg_cluster_wy_prod (7642589780522937440) ---------+----+-------------+-----+------------+-----+
| Member   | Host                 | Role         | State     | TL | Receive LSN | Lag | Replay LSN | Lag |
+----------+----------------------+--------------+-----------+----+-------------+-----+------------+-----+
| ubuntu11 | 192.168.152.121:9000 | Leader       | running   |  7 |             |     |            |     |
| ubuntu12 | 192.168.152.122:9000 | Sync Standby | streaming |  7 |   0/7000410 |   0 |  0/7000410 |   0 |
| ubuntu13 | 192.168.152.123:9000 | Replica      | streaming |  7 |   0/9000000 |   0 |  0/9000000 |   0 |
+----------+----------------------+--------------+-----------+----+-------------+-----+------------+-----+

原主节点日志，可以发现：replica has been created using basebackup，也就是说当前损坏的节点，会自动基于basebackup备份一份数据，自动恢复并加入集群，就像打不死的小强一样坚强。当然如果库比较大的情况就另说。

026-05-22 16:39:25,903 INFO: no action. I am (ubuntu13), the leader with the lock
2026-05-22 16:39:35,943 INFO: no action. I am (ubuntu13), the leader with the lock
2026-05-22 16:39:45,901 INFO: no action. I am (ubuntu13), the leader with the lock
2026-05-22 16:39:55,902 INFO: no action. I am (ubuntu13), the leader with the lock
2026-05-22 16:40:05,944 INFO: no action. I am (ubuntu13), the leader with the lock
2026-05-22 16:40:15,902 INFO: no action. I am (ubuntu13), the leader with the lock
2026-05-22 16:40:25,901 INFO: no action. I am (ubuntu13), the leader with the lock
2026-05-22 16:40:35,947 INFO: no action. I am (ubuntu13), the leader with the lock
2026-05-22 16:40:45,904 INFO: no action. I am (ubuntu13), the leader with the lock
2026-05-22 16:40:55,899 INFO: Lock owner: ubuntu13; I am ubuntu13
2026-05-22 16:40:57,570 ERROR: Failed to get list of machines from http://192.168.152.122:2379/v3: MaxRetryError("HTTPConnectionPool(host='192.168.152.122', port=2379): Max retries exceeded with url: /v3/cluster/member/list (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x7fd2642bc7c0>, 'Connection to 192.168.152.122 timed out. (connect timeout=1.6666666666666667)'))")
2026-05-22 16:40:57,573 INFO: no action. I am (ubuntu13), the leader with the lock
2026-05-22 16:41:05,902 INFO: no action. I am (ubuntu13), the leader with the lock
2026-05-22 16:41:15,901 INFO: no action. I am (ubuntu13), the leader with the lock
2026-05-22 16:41:25,905 INFO: no action. I am (ubuntu13), the leader with the lock
2026-05-22 16:41:35,944 INFO: no action. I am (ubuntu13), the leader with the lock
2026-05-22 16:41:45,903 INFO: no action. I am (ubuntu13), the leader with the lock
2026-05-22 16:41:55,908 INFO: no action. I am (ubuntu13), the leader with the lock
2026-05-22 16:42:05,945 INFO: no action. I am (ubuntu13), the leader with the lock
2026-05-22 16:42:15,905 INFO: no action. I am (ubuntu13), the leader with the lock
2026-05-22 16:42:25,902 INFO: no action. I am (ubuntu13), the leader with the lock
2026-05-22 16:42:35,943 INFO: no action. I am (ubuntu13), the leader with the lock
2026-05-22 16:42:45,901 INFO: no action. I am (ubuntu13), the leader with the lock
2026-05-22 16:42:55,901 INFO: no action. I am (ubuntu13), the leader with the lock
2026-05-22 16:43:05,944 INFO: no action. I am (ubuntu13), the leader with the lock
2026-05-22 16:43:15,901 INFO: no action. I am (ubuntu13), the leader with the lock
2026-05-22 16:43:25,904 INFO: no action. I am (ubuntu13), the leader with the lock
2026-05-22 16:43:35,906 INFO: Lock owner: ubuntu13; I am ubuntu13
2026-05-22 16:43:35,958 INFO: Leader key released
2026-05-22 16:43:35,961 INFO: released leader key voluntarily as data dir empty and currently leader
2026-05-22 16:43:35,961 INFO: Lock owner: None; I am ubuntu13
2026-05-22 16:43:36,003 INFO: waiting for leader to bootstrap
2026-05-22 16:43:36,016 INFO: Lock owner: ubuntu11; I am ubuntu13
2026-05-22 16:43:36,018 INFO: trying to bootstrap from leader 'ubuntu11'
2026-05-22 16:43:36,134 ERROR: Error when fetching backup: pg_basebackup exited with code=1
2026-05-22 16:43:36,135 WARNING: Trying again in 5 seconds
2026-05-22 16:43:37,069 INFO: Lock owner: ubuntu11; I am ubuntu13
2026-05-22 16:43:37,116 INFO: bootstrap from leader 'ubuntu11' in progress
2026-05-22 16:43:42,134 INFO: replica has been created using basebackup
2026-05-22 16:43:42,135 INFO: bootstrapped from leader 'ubuntu11'
2026-05-22 16:43:42,531 INFO: postmaster pid=25110
2026-05-22 16:43:43,580 INFO: Lock owner: ubuntu11; I am ubuntu13
2026-05-22 16:43:43,580 INFO: establishing a new patroni heartbeat connection to postgres
2026-05-22 16:43:43,602 INFO: Local timeline=7 lsn=0/9000000
2026-05-22 16:43:43,628 INFO: primary_timeline=7
2026-05-22 16:43:43,665 INFO: no action. I am (ubuntu13), a secondary, and following a leader (ubuntu11)
2026-05-22 16:43:47,112 INFO: no action. I am (ubuntu13), a secondary, and following a leader (ubuntu11)
2026-05-22 16:43:57,127 INFO: no action. I am (ubuntu13), a secondary, and following a leader (ubuntu11)
2026-05-22 16:44:07,584 INFO: no action. I am (ubuntu13), a secondary, and following a leader (ubuntu11)
2026-05-22 16:44:17,625 INFO: no action. I am (ubuntu13), a secondary, and following a leader (ubuntu11)
2026-05-22 16:44:27,579 INFO: no action. I am (ubuntu13), a secondary, and following a leader (ubuntu11)
2026-05-22 16:44:37,584 INFO: no action. I am (ubuntu13), a secondary, and following a leader (ubuntu11)
2026-05-22 16:44:47,627 INFO: no action. I am (ubuntu13), a secondary, and following a leader (ubuntu11)
2026-05-22 16:44:57,579 INFO: no action. I am (ubuntu13), a secondary, and following a leader (ubuntu11)
2026-05-22 16:45:07,587 INFO: no action. I am (ubuntu13), a secondary, and following a leader (ubuntu11)
2026-05-22 16:45:17,619 INFO: no action. I am (ubuntu13), a secondary, and following a leader (ubuntu11)

5，总结

本文通过三种实际的故障，严苛测试了patroni故障转移集群的高可用性，可以发现patroni可以完美处理各种故障，实现集群的高可用性，同时对于故障转移集群的ttl参数，以及loop_wait参数，在故障转移中的作用，做了实操性的验证，笔者本身也对这两个参数有了更加深刻的认识。

此内容由惯性聚合(RSS阅读器)自动聚合整理，仅供阅读参考。原文来自 — 版权归原作者所有。

推荐订阅源

博客园 - MSSQL123

1，自动故障转移场景1：主节点OS正常，patroni服务异常故障

2，自动故障转移场景2：主节点服务器断电

3，自动故障转移场景3：主节点网络分区

4，自动故障转移场景4：暴力删除主节点PostgreSQL数据文件

5，总结