【案例】invalid primary checkpoint record
问题 invalid primary checkpoint record
服务器因未正常归档 ，导至wal日志目录满，最终DB down掉，当启库的时候也异常。 这种情况也常出现在服务器断电的场景。
LOG,00000,"database system was interrupted while in recovery at 2022-04-08 09:08:03 HKT",,"This probably means that some data is corrupted and you will have to use the last backup for recovery.",,,,,,,""
LOG,00000,"invalid primary checkpoint record",,,,,,,,,""
PANIC,XX000,"could not locate a valid checkpoint record",,,,,,,,,""
LOG,00000,"startup process (PID 76560) was terminated by signal 6: Aborted",,,,,,,,,""
LOG,00000,"aborting startup due to startup process failure",,,,,,,,,""
LOG,00000,"database system is shut down",,,,,,,,,""处理 pg_resetwal
使用su 切换至postgres用户便于执行 pg_resetwal
su - postgres
[postgres@LXUATEDPD2 log]$ pg_resetwal -f $PGDATA
Write-ahead log reset
# 启动数据库
[postgres@LXUATEDPD2 log]$ pg_ctl start
waiting for server to start....2022-04-08 09:22:12.216 HKT [76634] LOG: starting PostgreSQL 12.9 on x86_64-pc-linux-gnu, compiled by gcc (GCC) 8.5.0 20210514 (Red Hat 8.5.0-4), 64-bit
2022-04-08 09:22:12.217 HKT [76634] LOG: listening on IPv4 address "0.0.0.0", port 5432
2022-04-08 09:22:12.218 HKT [76634] LOG: listening on Unix socket "/db_data/dwh/pg_data/.s.PGSQL.5432"
2022-04-08 09:22:12.328 HKT [76634] LOG: redirecting log output to logging collector process
2022-04-08 09:22:12.328 HKT [76634] HINT: Future log output will appear in directory "log".
done
server started注意事项
pg_resetwal会清空存储在pg_control文件中的wal和其他可选的控制信息。不到万不得已，可别使用这个命令。
执行该工具之后，数据库可以启动，但是可能会包含不一致的数据，因为会有事务部分提交。重启后，建议立即将数据dump出来，运行initdb并reload数据。检查数据一致性并根据需要进行数据修复。
需要显式的指定目录，pg_resetwal不会使用环境变量PGDATA。
参数-f表示强制执行pg_resetwal。
