Question

Max_packet_allowed设置自动重置为1024（1M）。我已在全球范围内将其设置为更高的值。但奇怪的是，有时在部署战争期间（并非总是如此），该值将重置为1M。此值也会随机重置。即使有一个mysql服务器重启，它也不会发生，因为它会从全局级别复制值。

这是my.cnf配置文件内容（ubuntu）：

#
# The MySQL database server configuration file.
#
# You can copy this to one of:
# - "/etc/mysql/my.cnf" to set global options,
# - "~/.my.cnf" to set user-specific options.
# 
# One can use all long options that the program supports.
# Run program with --help to get a list of available options and with
# --print-defaults to see which it would actually understand and use.
#
# For explanations see
# http://dev.mysql.com/doc/mysql/en/server-system-variables.html

# This will be passed to all mysql clients
# It has been reported that passwords should be enclosed with ticks/quotes
# escpecially if they contain "#" chars...
# Remember to edit /etc/mysql/debian.cnf when changing the socket location.
[client]
port        = 3306
socket      = /var/run/mysqld/mysqld.sock

# Here is entries for some specific programs
# The following values assume you have at least 32M ram

# This was formally known as [safe_mysqld]. Both versions are currently parsed.
[mysqld_safe]
socket      = /var/run/mysqld/mysqld.sock
nice        = 0

[mysqld]
#
# * Basic Settings
#
wait_timeout=115200
max_allowed_packet=500M
user        = mysql
pid-file    = /var/run/mysqld/mysqld.pid
socket      = /var/run/mysqld/mysqld.sock
port        = 3306
basedir     = /usr
datadir     = /var/lib/mysql
tmpdir      = /tmp
lc-messages-dir = /usr/share/mysql
skip-external-locking
#
# Instead of skip-networking the default is now to listen only on
# localhost which is more compatible and is not less secure.
#bind-address       = 127.0.0.1
#skip-networking
#
# * Fine Tuning
#
key_buffer      = 16M
max_allowed_packet  = 50M
thread_stack        = 192K
thread_cache_size       = 8
# This replaces the startup script and checks MyISAM tables if needed
# the first time they are touched
myisam-recover         = BACKUP
max_connections        = 250
#table_cache            = 64
#thread_concurrency     = 10
#
# * Query Cache Configuration
#
query_cache_limit   = 16M
query_cache_size        = 16M
#
# * Logging and Replication
#
# Both location gets rotated by the cronjob.
# Be aware that this log type is a performance killer.
# As of 5.1 you can enable the log at runtime!
#general_log_file        = /var/log/mysql/mysql.log
#general_log             = 1
#
# Error log - should be very few entries.
#
log_error = /var/log/mysql/error.log
#
# Here you can see queries with especially long duration
#log_slow_queries   = /var/log/mysql/mysql-slow.log
#long_query_time = 2
#log-queries-not-using-indexes
#
# The following can be used as easy to replay backup logs or for replication.
# note: if you are setting up a replication slave, see README.Debian about
#       other settings you may need to change.
#server-id      = 1
#log_bin            = /var/log/mysql/mysql-bin.log
expire_logs_days    = 10
max_binlog_size         = 100M
#binlog_do_db       = include_database_name
#binlog_ignore_db   = include_database_name
#
# * InnoDB
#
# InnoDB is enabled by default with a 10MB datafile in /var/lib/mysql/.
# Read the manual for more InnoDB related options. There are many!
#
# * Security Features
#
# Read the manual, too, if you want chroot!
# chroot = /var/lib/mysql/
#
# For generating SSL certificates I recommend the OpenSSL GUI "tinyca".
#
# ssl-ca=/etc/mysql/cacert.pem
# ssl-cert=/etc/mysql/server-cert.pem
# ssl-key=/etc/mysql/server-key.pem



[mysqldump]
quick
quote-names
max_allowed_packet  = 100M

[mysql]
#no-auto-rehash # faster start of mysql but no tab completition
max_allowed_packet      = 160M

[isamchk]
key_buffer      = 16M

#
# * IMPORTANT: Additional settings that can override those from this file!
#   The files must end with '.cnf', otherwise they'll be ignored.
#
!includedir /etc/mysql/conf.d/

Answer 1

必须有一段代码更改max_allowed_packet的默认值。

您可以尝试记录查询以确定哪个用户或进程正在更改此值。

作为一种解决方法，您可以尝试仅为管理员用户设置“超级”权限，以防止他人更改max_allowed_packet。

Answer 2

我发现如果你的mysql服务器可以从任何主机（root @％）进行远程连接，那么有人会试图攻击你的系统。

有一些信息：

1）max_allowed_packet自动更改为1024。

2）他们要添加到您系统的新用户。用户名是：＆＃34; mysqld＆＃34;和＆＃34;服务器＆＃34;。 MySql没有默认用户。

3）他们也在＆＃34; mysql＆＃34;上添加新表。数据库中。

4）如果您的互联网连接速度不是很快，那么当您远程转储数据库时，您的互联网连接速度会很慢。

我建议：

更改root密码。（不要使用简单的密码）
如果可能，禁止远程连接到Mysql。
不要使用默认端口。（3306）为Mysql使用另一个端口。

Max_packet_allowed自动重置

2 个答案: