pg在11之前，有原生的range分区和list分区，但是没有原生的hash分区。 hash分区是需要通过pg_pathman插件来实现。 如果你从原来pg 10版本+pg_pathman实现hash分区，且分区数比较多，比如1024个分区，那么到你升级到pg 11之后，如果采用了原生分区，你会发现 […]
mysql awr脚本部署
这个脚本是用来在mysql数据库中创建一个myawr数据库，记录数据库中记录active session。 cat /root/user/myawr.sql
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--先创建myawr数据库 create database myawr DEFAULT CHARACTER SET utf8mb4; |
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use myawr; CREATE TABLE myawr.`processliststatus` ( `ID` bigint(21) unsigned NOT NULL DEFAULT '0', `USER` varchar(32) NOT NULL DEFAULT '', `HOST` varchar(64) NOT NULL DEFAULT '', `DB` varchar(64) DEFAULT NULL, `COMMAND` varchar(16) NOT NULL DEFAULT '', `TIME` int(7) NOT NULL DEFAULT '0', `STATE` varchar(64) DEFAULT NULL, `INFO` longtext, `clock` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP, `snapid` bigint(20) DEFAULT NULL, KEY `idx_clock` (`clock`), key idx_snapid(snapid) ); CREATE TABLE myawr.`mysqldumplog` ( `ID` bigint unsigned NOT NULL DEFAULT '0', `USER` varchar(32) NOT NULL DEFAULT '', `HOST` varchar(64) NOT NULL DEFAULT '', `DB` varchar(64) DEFAULT NULL, `COMMAND` varchar(16) NOT NULL DEFAULT '', `TIME` int NOT NULL DEFAULT '0', `STATE` varchar(64) DEFAULT NULL, `INFO` longtext, `clock` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP, KEY `idx_clock` (`clock`) ); CREATE TABLE myawr.`lockstatus` ( `clock` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP, `wating_trx_state` varchar(255) DEFAULT NULL, `waiting_trx_id` bigint DEFAULT NULL, `waiting_thread` bigint DEFAULT NULL, `waiting_query` varchar(2000) DEFAULT NULL, `blocking_trx_state` varchar(255) DEFAULT NULL, `blocking_trx_id` bigint DEFAULT NULL, `blocking_thread` bigint DEFAULT NULL, `blocking_query` varchar(2000) DEFAULT NULL, `snapid` bigint(20) DEFAULT NULL, KEY `idx_clock` (`clock`), key idx_snapid(snapid) ); DELIMITER $$ CREATE PROCEDURE myawr.`partition_verify`(SCHEMANAME VARCHAR(64), TABLENAME VARCHAR(64), HOURLYINTERVAL INT(11)) BEGIN DECLARE PARTITION_NAME VARCHAR(16); DECLARE RETROWS INT(11); DECLARE FUTURE_TIMESTAMP TIMESTAMP; /* * Check if any partitions exist for the given SCHEMANAME.TABLENAME. */ SELECT COUNT(1) INTO RETROWS FROM information_schema.partitions WHERE table_schema = SCHEMANAME AND table_name = TABLENAME AND partition_name IS NULL; /* * If partitions do not exist, go ahead and partition the table */ IF RETROWS = 1 THEN /* * Take the current date at 00:00:00 and add HOURLYINTERVAL to it. This is the timestamp below which we will store values. * We begin partitioning based on the beginning of a day. This is because we don't want to generate a random partition * that won't necessarily fall in line with the desired partition naming (ie: if the hour interval is 24 hours, we could * end up creating a partition now named "p201403270600" when all other partitions will be like "p201403280000"). */ SET FUTURE_TIMESTAMP = TIMESTAMPADD(HOUR, HOURLYINTERVAL, CONCAT(CURDATE(), " ", '00:00:00')); SET PARTITION_NAME = DATE_FORMAT(CURDATE(), 'p%Y%m%d%H00'); -- Create the partitioning query SET @__PARTITION_SQL = CONCAT("ALTER TABLE ", SCHEMANAME, ".", TABLENAME, " PARTITION BY RANGE(UNIX_TIMESTAMP(`clock`))"); SET @__PARTITION_SQL = CONCAT(@__PARTITION_SQL, "(PARTITION ", PARTITION_NAME, " VALUES LESS THAN (", UNIX_TIMESTAMP(FUTURE_TIMESTAMP), "));"); -- Run the partitioning query PREPARE STMT FROM @__PARTITION_SQL; EXECUTE STMT; DEALLOCATE PREPARE STMT; END IF; END $$ CREATE PROCEDURE myawr.`partition_create` ( SCHEMANAME VARCHAR ( 64 ), TABLENAME VARCHAR ( 64 ), PARTITIONNAME VARCHAR ( 64 ), CLOCK INT ) BEGIN /* SCHEMANAME = The DB schema in which to make changes TABLENAME = The table with partitions to potentially delete PARTITIONNAME = The name of the partition to create */ /* Verify that the partition does not already exist */ DECLARE RETROWS INT; SELECT COUNT( 1 ) INTO RETROWS FROM information_schema.PARTITIONS WHERE table_schema = SCHEMANAME AND table_name = TABLENAME AND partition_description >= CLOCK; IF RETROWS = 0 THEN /* 1. Print a message indicating that a partition was created. 2. Create the SQL to create the partition. 3. Execute the SQL from #2. */ SELECT CONCAT( "partition_create(", SCHEMANAME, ",", TABLENAME, ",", PARTITIONNAME, ",", CLOCK, ")" ) AS msg; SET @SQL = CONCAT( 'ALTER TABLE ', SCHEMANAME, '.', TABLENAME, ' ADD PARTITION (PARTITION ', PARTITIONNAME, ' VALUES LESS THAN (', CLOCK, '));' ); PREPARE STMT FROM @SQL; EXECUTE STMT; DEALLOCATE PREPARE STMT; END IF; END $$ CREATE PROCEDURE myawr.`partition_drop` ( SCHEMANAME VARCHAR ( 64 ), TABLENAME VARCHAR ( 64 ), DELETE_BELOW_PARTITION_DATE BIGINT ) BEGIN /* SCHEMANAME = The DB schema in which to make changes TABLENAME = The table with partitions to potentially delete DELETE_BELOW_PARTITION_DATE = Delete any partitions with names that are dates older than this one (yyyy-mm-dd) */ DECLARE done INT DEFAULT FALSE; DECLARE drop_part_name VARCHAR ( 16 ); /* Get a list of all the partitions that are older than the date in DELETE_BELOW_PARTITION_DATE. All partitions are prefixed with a "p", so use SUBSTRING TO get rid of that character. */ DECLARE myCursor CURSOR FOR SELECT partition_name FROM information_schema.PARTITIONS WHERE table_schema = SCHEMANAME AND table_name = TABLENAME AND CAST( SUBSTRING( partition_name FROM 2 ) AS UNSIGNED ) < DELETE_BELOW_PARTITION_DATE; DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE; /* Create the basics for when we need to drop the partition. Also, create @drop_partitions to hold a comma-delimited list of all partitions that should be deleted. */ SET @alter_header = CONCAT( "ALTER TABLE ", SCHEMANAME, ".", TABLENAME, " DROP PARTITION " ); SET @drop_partitions = ""; /* Start looping through all the partitions that are too old. */ OPEN myCursor; read_loop : LOOP FETCH myCursor INTO drop_part_name; IF done THEN LEAVE read_loop; END IF; SET @drop_partitions = IF ( @drop_partitions = "", drop_part_name, CONCAT( @drop_partitions, ",", drop_part_name ) ); END LOOP; IF @drop_partitions != "" THEN /* 1. Build the SQL to drop all the necessary partitions. 2. Run the SQL to drop the partitions. 3. Print out the table partitions that were deleted. */ SET @full_sql = CONCAT( @alter_header, @drop_partitions, ";" ); PREPARE STMT FROM @full_sql; EXECUTE STMT; DEALLOCATE PREPARE STMT; SELECT CONCAT( SCHEMANAME, ".", TABLENAME ) AS `table`, @drop_partitions AS `partitions_deleted`; ELSE /* No partitions are being deleted, so print out "N/A" (Not applicable) to indicate that no changes were made. */ SELECT CONCAT( SCHEMANAME, ".", TABLENAME ) AS `table`, "N/A" AS `partitions_deleted`; END IF; END $$ CREATE PROCEDURE myawr.`partition_maintenance`(SCHEMA_NAME VARCHAR(32), TABLE_NAME VARCHAR(32), KEEP_DATA_DAYS INT, HOURLY_INTERVAL INT, CREATE_NEXT_INTERVALS INT) BEGIN DECLARE OLDER_THAN_PARTITION_DATE VARCHAR(16); DECLARE PARTITION_NAME VARCHAR(16); DECLARE OLD_PARTITION_NAME VARCHAR(16); DECLARE LESS_THAN_TIMESTAMP INT; DECLARE CUR_TIME INT; CALL partition_verify(SCHEMA_NAME, TABLE_NAME, HOURLY_INTERVAL); SET CUR_TIME = UNIX_TIMESTAMP(DATE_FORMAT(NOW(), '%Y-%m-%d 00:00:00')); SET @__interval = 1; create_loop: LOOP IF @__interval > CREATE_NEXT_INTERVALS THEN LEAVE create_loop; END IF; SET LESS_THAN_TIMESTAMP = CUR_TIME + (HOURLY_INTERVAL * @__interval * 3600); SET PARTITION_NAME = FROM_UNIXTIME(CUR_TIME + HOURLY_INTERVAL * (@__interval - 1) * 3600, 'p%Y%m%d%H00'); IF(PARTITION_NAME != OLD_PARTITION_NAME) THEN CALL partition_create(SCHEMA_NAME, TABLE_NAME, PARTITION_NAME, LESS_THAN_TIMESTAMP); END IF; SET @__interval=@__interval+1; SET OLD_PARTITION_NAME = PARTITION_NAME; END LOOP; SET OLDER_THAN_PARTITION_DATE=DATE_FORMAT(DATE_SUB(NOW(), INTERVAL KEEP_DATA_DAYS DAY), '%Y%m%d0000'); CALL partition_drop(SCHEMA_NAME, TABLE_NAME, OLDER_THAN_PARTITION_DATE); END$$ CREATE PROCEDURE myawr.proc_awr_killdump( ) BEGIN declare dump_id INT default false; DECLARE done INT DEFAULT FALSE; DECLARE myCursor CURSOR FOR SELECT id FROM information_schema.PROCESSLIST WHERE INFO like 'SELECT /*!40001 SQL_NO_CACHE */ * FROM%'; DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE; SET @dump_id =''; OPEN myCursor; read_loop : LOOP FETCH myCursor INTO dump_id; IF done THEN LEAVE read_loop; END IF; insert into myawr.mysqldumplog(ID,USER,HOST,DB,COMMAND,TIME,STATE,INFO) select ID,USER,HOST,DB,COMMAND,TIME,STATE,INFO from information_schema.processlist where id=dump_id; call mysql.rds_kill(dump_id); END LOOP; END $$ CREATE procedure myawr.proc_awr_getstatus() begin declare insertSessionCount INT default 0; -- 声明insert会话的计数器 set @ha=unix_timestamp(now()); -- 查看是否有insert 会话 select count(*) into insertSessionCount from information_schema.processlist where INFO like 'insert into myawr.processliststatus%'; -- 如果之前存在未结束的insert会话，则本次不insert IF insertSessionCount <1 THEN -- 排除非活跃会话和系统会话,并做截断操作 insert into myawr.processliststatus(ID,USER,HOST,DB,COMMAND,TIME,STATE,INFO,snapid) select ID,USER,HOST,DB,COMMAND,TIME,STATE,substring(INFO,1,3000), @ha from information_schema.processlist where COMMAND not in ('Sleep','Daemon','Binlog Dump GTID') and INFO not like 'insert into myawr.processliststatus%'; END IF; insert into myawr.lockstatus(wating_trx_state,waiting_trx_id,waiting_thread,waiting_query,blocking_trx_state,blocking_trx_id,blocking_thread,blocking_query,snapid) SELECT r.trx_state wating_trx_state,r.trx_id waiting_trx_id,r.trx_mysql_thread_Id waiting_thread,r.trx_query waiting_query,b.trx_state blocking_trx_state,b.trx_id blocking_trx_id,b.trx_mysql_thread_id blocking_thread,b.trx_query blocking_query,@ha FROM information_schema.innodb_lock_waits w INNER JOIN information_schema.innodb_trx b ON b.trx_id = w.blocking_trx_id INNER JOIN information_schema.innodb_trx r ON r.trx_id = w.requesting_trx_id; end $$ create procedure myawr.proc_awr_enable(proc_name varchar(64)) begin /*declare proc_cursor varchar(64) default false; DECLARE done INT DEFAULT FALSE; DECLARE myCursor CURSOR FOR select name from mysql.event where db='myawr' and name like 'event\_awr\_%' and name not in ('event_awr_resetpartition'); DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;*/ if proc_name = 'all' then /*SET @proc_cursor =''; OPEN myCursor; read_loop : LOOP FETCH myCursor INTO proc_cursor; IF done THEN LEAVE read_loop; END IF; alter event proc_cursor enable; END LOOP;*/ select "抱歉，该参数现在还没能实现，敬请期待" as msg; elseif proc_name = 'killdump' then alter event event_awr_killdump enable; select "enable event_awr_killdump succeed ~" as msg; elseif proc_name = 'getmysqlstatus' then alter event event_awr_getMysqlStatus enable; select "enable event_awr_getMysqlStatus succeed ~" as msg; else select "参量输入有误抑或没有布置awr脚本！" as msg; end if; end $$ create procedure myawr.proc_awr_disable(proc_name varchar(64)) begin /*declare proc_cursor varchar(64) default false; DECLARE done INT DEFAULT FALSE; DECLARE myCursor CURSOR FOR select name from mysql.event where db='myawr' and name like 'event\_awr\_%' and name not in ('event_awr_resetpartition'); DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;*/ if proc_name = 'all' then /*SET @proc_cursor =''; OPEN myCursor; read_loop : LOOP FETCH myCursor INTO proc_cursor; IF done THEN LEAVE read_loop; END IF; alter event proc_cursor enable; END LOOP;*/ select "抱歉，该参数现在还没能实现，敬请期待" as msg; elseif proc_name = 'killdump' then alter event event_awr_killdump disable; select "disable event_awr_killdump succeed ~" as msg; elseif proc_name = 'getmysqlstatus' then alter event event_awr_getMysqlStatus disable; select "disable event event_awr_getMysqlStatus succeed ~" as msg; else select "参量输入有误抑或没有布置awr脚本！" as msg; end if; end $$ CREATE PROCEDURE myawr.myawr_help() BEGIN select " 1、实现功能： 1.1、默认每10s会收集一次mysql的processlist状态和锁等待情况。 1.2、默认每9s检查是否存在dump操作，如果存在将会kill线程，并且将此记录在mysqldump_log表中。 2、更改参数： 2.1、修改脚本收集或检查的频率 最小时间不应该小于7s，否则可能会对数据库性能产生影响。 mysql> call proc_awr_changeint('killdump',5); 2.2、启用或停止脚本部分功能 mysql> call proc_awr_enable('all'); mysql> call proc_awr_enable('killdump'); mysql> call proc_awr_enable('getmysqlstatus'); mysql> call proc_awr_disable('all'); mysql> call proc_awr_disable('killdump'); mysql> call proc_awr_disable('getmysqlstatus'); 3、dump操作： 3.1、停止非法dump监控事件 mysql> call proc_awr_disable('killdump'); 4.2、进行dump操作 mysqldump --single-transaction *** 3.3、恢复监控事件 mysql> call proc_awr_enable('killdump');" AS help_message; end $$ create event myawr.event_awr_getMysqlStatus ON SCHEDULE -- 每隔10秒运行 every 10 second on completion preserve do call proc_awr_getstatus(); $$ CREATE EVENT myawr.event_awr_killdump ON SCHEDULE -- 每隔9秒运行 EVERY 9 SECOND ON COMPLETION PRESERVE DO CALL proc_awr_killdump (); $$ create event myawr.event_awr_resetpartition ON SCHEDULE every 1 day on completion preserve do begin call partition_maintenance('myawr','processliststatus',7,24,30); call partition_maintenance('myawr','lockstatus',7,24,30); end $$ |
SQL Server数据文件结构
Data file 结构： 第一个extent:
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page 0 : File Header，注m_type = 15，Metadata: ObjectId = 99 page 1 : PFS( page free space)，注m_type = 11，Metadata: ObjectId = 99 page 2 : GAM ( global allocation map)，注m_type = 8，Metadata: ObjectId = 99，每个GAM管理4GB的页面，所以每隔4GB大小的页面，会有一个GAM。 page 3 : SGAM ( shared global allocation map)，注m_type = 9，Metadata: ObjectId = 99 page 4 : 空的，注m_type = 0，Metadata: ObjectId = 0 page 5 : 空的，注m_type = 0，Metadata: ObjectId = 0 page 6 : DCM（differential change map），注m_type = 16，Metadata: ObjectId = 99 page 7 ：BCM（bulk change map），注m_type = 17，Metadata: ObjectId = 99 |
注意，如果大temp文件（一个超过4G）的page latch，往往是在temp数据文件的第一个extent的第2个page上，其争用可以用下面的sql监控： [crayon-673e […]
数据库内查询pg的表结构定义
需要利用到plperlu和自己写一个system函数。
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-bash-4.2$ psql psql (9.6.2) Type "help" for help. postgres=# create extension plperlu; CREATE EXTENSION postgres=# \dx List of installed extensions Name | Version | Schema | Description ---------+---------+------------+---------------------------------------- plperlu | 1.0 | pg_catalog | PL/PerlU untrusted procedural language plpgsql | 1.0 | pg_catalog | PL/pgSQL procedural language (2 rows) |
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postgres=# CREATE OR REPLACE FUNCTION system(text) RETURNS text postgres-# AS 'my $cmd=shift; return `cd /tmp;$cmd`;' LANGUAGE plperlu; CREATE FUNCTION postgres=# postgres=# |
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postgres=# select system('pg_dump -s -t orasup_test1 dbinfo2 |egrep -v "^--|^$"'); system ----------------------------------------------------- SET statement_timeout = 0; + SET lock_timeout = 0; + SET idle_in_transaction_session_timeout = 0; + SET client_encoding = 'UTF8'; + SET standard_conforming_strings = on; + SET check_function_bodies = false; + SET client_min_messages = warning; + SET row_security = off; + SET search_path = public, pg_catalog; + SET default_tablespace = ''; + SET default_with_oids = false; + CREATE TABLE orasup_test1 ( + a integer, + b character varying(200) + ); + ALTER TABLE orasup_test1 OWNER TO djidba_rw; + CREATE INDEX idx_b ON orasup_test1 USING btree (b);+ (1 row) postgres=# postgres=# |
How to upgrade aws rds postgresql
## 0. Read the summary of upgrade pg https://docs.aws.amazon.com/zh_cn/AmazonRDS/latest/UserGuide/USER_UpgradeDBInstance.PostgreSQL.html ## 1. Prepare […]
pg常用大小查询
查出所有数据库大小：
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select pg_database.datname, pg_database_size(pg_database.datname) AS size from pg_database order by size desc; |
查出所有表按大小排序并分离data与index：
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SELECT table_name, pg_size_pretty(table_size) AS table_size, pg_size_pretty(indexes_size) AS indexes_size, pg_size_pretty(total_size) AS total_size FROM ( SELECT table_name, pg_table_size(table_name) AS table_size, pg_indexes_size(table_name) AS indexes_size, pg_total_relation_size(table_name) AS total_size FROM ( SELECT ('"' || table_schema || '"."' || table_name || '"') AS table_name FROM information_schema.tables ) AS all_tables ORDER BY total_size DESC ) AS pretty_sizes; |
查看索引大小：
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select relname as table_name,pg_size_pretty(pg_relation_size(relid)) as table_size, indexrelname as index_name, pg_size_pretty(pg_relation_size(indexrelid)) as index_size from pg_stat_user_indexes order by pg_relation_size(indexrelid) desc; |
数据库应急杀进程脚本
Oracle： （1）数据库内操作
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--单实例： select 'alter system kill session '''||s.sid||','||s.SERIAL#||''' immediate;' from v$session s where s.status='INACTIVE' --状态为非活跃 and s.USERNAME= 'ZZZ' --用户为ZZZZ s.type<>'BACKGROUND' --不为oracle后台进程 and program not like '%(J0%' --不为oracle的JOB进程 order by s.LOGON_TIME asc,sql_exec_start asc; |
（2）操作系统中操作（要求登录到数据库主机）
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## kill掉所有local=no的非本地连接进程 ps -ef|grep -v grep|grep LOCAL=NO|awk '{print $2}'|xargs kill -9 |
SQL Server:
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--kill 被阻塞会话 select 'kill '+cast(spid as varchar) FROM sys.sysprocesses sp where sp.blocked !=0 and sp.spid != sp.blocked and loginame='XXX'; |
pg报错current transaction is aborted
在一个事务中，pg报错了current transaction is aborted：
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mumy_corehrdban_psdb=> begin; BEGIN mumy_corehrdban_psdb=> select * from orasup_test1 ; a --- 1 2 3 (3 rows) mumy_corehrdban_psdb=> insert into orasup_test1 values(111); INSERT 0 1 mumy_corehrdban_psdb=> select * from not_exist; ERROR: relation "not_exist" does not exist LINE 1: select * from not_exist; ^ mumy_corehrdban_psdb=> insert into orasup_test1 values(222); ERROR: current transaction is aborted, commands ignored until end of transaction block mumy_corehrdban_psdb=> select * from orasup_test1; ERROR: current transaction is aborted, commands ignored until end of transaction block mumy_corehrdban_psdb=> mumy_corehrdban_psdb=> \d ERROR: current transaction is aborted, commands ignored until end of transaction block mumy_corehrdban_psdb=> mumy_corehrdban_psdb=> mumy_corehrdban_psdb=> rollback; ROLLBACK mumy_corehrdban_psdb=> select * from orasup_test1; a --- 1 2 3 (3 rows) mumy_corehrdban_psdb=> |
原因是在一个事务中，pg如果遇到的Error的报错，会忽略后续的命令，后续所有命令都会报错：current transaction is abor […]
postgresql 检索当前数据库中所有的分区表
pg 10由于没有hash分区，而pg_pathman一直都是支持多种分区的。所以如果某些pg 11以前的系统，可能会混合部署pg原生分区和pg_pathman。 要检查这种混合部署环境中的分区情况，可以用下面的sql：
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select b.parent::text as part_table, 'native partition' as part_tool, CASE WHEN a.partstrat='r' THEN 'range' WHEN a.partstrat='l' THEN 'list' WHEN a.partstrat='h' THEN 'hash' ELSE 'other' END as part_type, b.cnt as part_cnt from pg_partitioned_table a, (SELECT parent.oid, parent.relname AS parent, COUNT(*) as cnt FROM pg_inherits JOIN pg_class parent ON pg_inherits.inhparent = parent.oid JOIN pg_class child ON pg_inherits.inhrelid = child.oid JOIN pg_namespace nmsp_parent ON nmsp_parent.oid = parent.relnamespace JOIN pg_namespace nmsp_child ON nmsp_child.oid = child.relnamespace GROUP BY oid,parent) b where a.partrelid=b.oid union all select parent::text, 'pg_pathman', CASE WHEN parttype=1 THEN 'hash' WHEN parttype=2 THEN 'range' ELSE 'other' END , count(*) from pathman_partition_list group by parent,parttype |
显示结果如下 […]
小记MySQL的锁和事务
（一）先说明一下定义： 1. 读现象（Read phenomena）： SQL 92标准规定了3种不同的读现象。脏读、不可重复读和幻读。分别解释一下。 1.1 脏读： A dirty read (aka uncommitted dependency) occurs when a transactio […]
某系统物理机本地存储和虚拟机SAN存储性能对比测试
本文用fio测试了某系统的物理机本地存储和虚拟机使用SAN存储的性能对比。 FIO测试原始数据 说明： 虚拟机在小块文件的IO处理能力上，要比物理机处理的好。而物理机在大块文件的处理能力上 […]
华硕AC86U路由器不定期连不上公网的解决办法
华硕的路由器，不知什么原因，总是会不定期连不上公网，在网络地图的互联网状态，会显示连接失败的状态。 测试了一下发现，ACU86U在上级的光猫路由器比如重启，比如间歇断网之后，哪怕上级路由器恢复，ac86u还是无法重连外网。我测试了断开上级的光猫路由的电源插头再插上，发现AC86U不会自动重拨，AC8 […]