Question

我正在开发一个 Docker应用程序，该应用程序使用MySQL存储非常大的数据库（这是由于遗留原因所致）。 此主机已安装在主机上。

今天我从事的工作已经有1到2个月了，突然之间我无法与数据库进行通信了。

数据库的 uri 几个月来一直是相同的： jdbc:mysql://localhost:3306/dbname?verifyServerCertificate=false&useSSL=true&useJDBCCompliantTimezoneShift=true&useLegacyDatetimeCode=false&serverTimezone=UTC

一旦我尝试从运行在虚拟机上的应用程序连接到数据库，就会收到：

java.sql.SQLException: Cannot create PoolableConnectionFactory (Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.)
...
Caused by: java.net.ConnectException: Connection timed out

有罪代码是这样的：

private static boolean checkForExistence(String dbName) {
    boolean exists = false;
    BasicDataSource dataSource = new BasicDataSource();

    dataSource.setDriverClassName(JDBC_DRIVER); //com.mysql.cj.jdbc.Driver
    dataSource.setUrl(this.url); //that's the uri provided before
    dataSource.setUsername(USER);
    dataSource.setPassword(PASS);

    Connection conn = null;
    Statement stmnt = null;
    ResultSet dbs = null;
    try {       
        conn = dataSource.getConnection(); //And this is the line that triggers the exception.
        System.out.println(conn!=null);
        dbs = conn.getMetaData().getCatalogs();

        while(dbs.next() && !exists)
            if(dbs.getString(1).equals(dbName))
                exists = true;

    } catch (SQLException e) {
        e.printStackTrace();
    } finally {
        try {
            if(conn != null)
                conn.close();
            if(stmnt != null)
                stmnt.close();
            if(dbs != null)
                dbs.close();
            if(dataSource != null)
                dataSource.close();
        } catch (SQLException e) {
                logger.error(e.getMessage());
                return exists;
        }
    }

    return exists;
}

我尝试了以下操作：

在我的本地计算机上：telnet <public ip of the VM> 3306->连接超时
从我的本地计算机上：mysql -h<public ip of the VM> -u user -p-> ERROR 2003 (HY000): Can't connect to MySQL server on 'remoteHostname.com' (110)
从VM内部：nc localhost 3306->我可以进入。
从VM内部：mysql -h127.0.0.1 -u user -p->我可以进入。
从VM内部：mysql -h<public ip address> -u user -p->我可以进入。

如果我运行netstat -tulpn | grep 3306，我会得到：

tcp6       0      0 :::3306                 :::*                    LISTEN      -                   
tcp6       0      0 :::33060                :::*                    LISTEN      -

这是my.cnf：

[mysqld]
default_authentication_plugin=mysql_native_password
datadir=/local/user/mysql
socket=/var/lib/mysql/mysql.sock
general_log_file=/var/log/mysql.log
general_log=1
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid

我可以通过 PhpMyAdmin 连接到数据库，但是我认为这是由于使用了Socket连接。

如果我同时检查/var/log/mysql.log和/var/log/mysqld.log（这是有关错误的信息），则没有任何证据。基本上，当我尝试连接时，这些都不显示。

编辑： 如果我使用相同的设置连接到mysql的本地计算机实例，则一切正常。那么这可能与网络问题有关吗？还是由于某种原因，VM的mysql实例不再接受tcp连接？

重新编辑：检入/var/log/messages后，我发现主机已用完磁盘空间。从那时起，接口docker0进入blocked state，然后进入disabled state循环。

配置：

使用RHEL7远程VM
32核CPU
64GB RAM
MySQL 8.0.13-MySQL社区服务器-GPL
PhpMyAdmin 4.8.4

Answer 1

在问题的“重新编辑”部分中，我指定了新的详细信息。我仍然无法使用旧配置正确运行应用程序，但是在<Window.Resources> <Style x:Key="DatePickerStyle" TargetType="{x:Type DatePicker}"> <Setter Property="Foreground" Value="#FF333333"/> <Setter Property="IsTodayHighlighted" Value="True"/> <Setter Property="SelectedDateFormat" Value="Short"/> <Setter Property="Background" Value="Transparent"/> <Setter Property="Padding" Value="2"/> <Setter Property="BorderBrush"> <Setter.Value> <LinearGradientBrush EndPoint=".5,0" StartPoint=".5,1"> <GradientStop Color="#FFA3AEB9" Offset="0"/> <GradientStop Color="#FF8399A9" Offset="0.375"/> <GradientStop Color="#FF718597" Offset="0.375"/> <GradientStop Color="#FF617584" Offset="1"/> </LinearGradientBrush> </Setter.Value> </Setter> <Setter Property="BorderThickness" Value="1"/> <Setter Property="HorizontalContentAlignment" Value="Stretch"/> <Setter Property="Template"> <Setter.Value> <ControlTemplate TargetType="{x:Type DatePicker}"> <Border BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Padding="{TemplateBinding Padding}"> <VisualStateManager.VisualStateGroups> <VisualStateGroup x:Name="CommonStates"> <VisualState x:Name="Normal"/> <VisualState x:Name="Disabled"> <Storyboard> <DoubleAnimation Duration="0" To="1" Storyboard.TargetProperty="Opacity" Storyboard.TargetName="PART_DisabledVisual"/> </Storyboard> </VisualState> </VisualStateGroup> </VisualStateManager.VisualStateGroups> <Grid x:Name="PART_Root" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"> <Grid.Resources> <SolidColorBrush x:Key="DisabledBrush" Color="#A5FFFFFF"/> <ControlTemplate x:Key="DropDownButtonTemplate" TargetType="{x:Type Button}"> <Grid> <VisualStateManager.VisualStateGroups> <VisualStateGroup x:Name="CommonStates"> <VisualStateGroup.Transitions> <VisualTransition GeneratedDuration="0"/> <VisualTransition GeneratedDuration="0:0:0.1" To="MouseOver"/> <VisualTransition GeneratedDuration="0:0:0.1" To="Pressed"/> </VisualStateGroup.Transitions> <VisualState x:Name="Normal"/> <VisualState x:Name="MouseOver"> <Storyboard> <ColorAnimation Duration="0" To="#FF448DCA" Storyboard.TargetProperty="(Border.Background).(SolidColorBrush.Color)" Storyboard.TargetName="Background"/> <ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[3].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient"> <SplineColorKeyFrame KeyTime="0" Value="#7FFFFFFF"/> </ColorAnimationUsingKeyFrames> <ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[2].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient"> <SplineColorKeyFrame KeyTime="0" Value="#CCFFFFFF"/> </ColorAnimationUsingKeyFrames> <ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[1].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient"> <SplineColorKeyFrame KeyTime="0" Value="#F2FFFFFF"/> </ColorAnimationUsingKeyFrames> </Storyboard> </VisualState> <VisualState x:Name="Pressed"> <Storyboard> <ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(SolidColorBrush.Color)" Storyboard.TargetName="Background"> <SplineColorKeyFrame KeyTime="0" Value="#FF448DCA"/> </ColorAnimationUsingKeyFrames> <DoubleAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(UIElement.Opacity)" Storyboard.TargetName="Highlight"> <SplineDoubleKeyFrame KeyTime="0" Value="1"/> </DoubleAnimationUsingKeyFrames> <ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[1].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient"> <SplineColorKeyFrame KeyTime="0" Value="#EAFFFFFF"/> </ColorAnimationUsingKeyFrames> <ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[2].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient"> <SplineColorKeyFrame KeyTime="0" Value="#C6FFFFFF"/> </ColorAnimationUsingKeyFrames> <ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[3].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient"> <SplineColorKeyFrame KeyTime="0" Value="#6BFFFFFF"/> </ColorAnimationUsingKeyFrames> <ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[0].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient"> <SplineColorKeyFrame KeyTime="0" Value="#F4FFFFFF"/> </ColorAnimationUsingKeyFrames> </Storyboard> </VisualState> <VisualState x:Name="Disabled"/> </VisualStateGroup> </VisualStateManager.VisualStateGroups> <Grid Background="#11FFFFFF" FlowDirection="LeftToRight" HorizontalAlignment="Center" Height="18" Margin="0" VerticalAlignment="Center" Width="19"> <Grid.ColumnDefinitions> <ColumnDefinition Width="20*"/> <ColumnDefinition Width="20*"/> <ColumnDefinition Width="20*"/> <ColumnDefinition Width="20*"/> </Grid.ColumnDefinitions> <Grid.RowDefinitions> <RowDefinition Height="23*"/> <RowDefinition Height="19*"/> <RowDefinition Height="19*"/> <RowDefinition Height="19*"/> </Grid.RowDefinitions> <Border x:Name="Highlight" BorderBrush="#FF45D6FA" BorderThickness="1" Grid.ColumnSpan="4" CornerRadius="0,0,1,1" Margin="-1" Opacity="0" Grid.Row="0" Grid.RowSpan="4"/> <Border x:Name="Background" BorderBrush="#FFFFFFFF" BorderThickness="1" Background="#FF1F3B53" Grid.ColumnSpan="4" CornerRadius=".5" Margin="0,-1,0,0" Opacity="1" Grid.Row="1" Grid.RowSpan="3"/> <Border x:Name="BackgroundGradient" BorderBrush="#BF000000" BorderThickness="1" Grid.ColumnSpan="4" CornerRadius=".5" Margin="0,-1,0,0" Opacity="1" Grid.Row="1" Grid.RowSpan="3"> <Border.Background> <LinearGradientBrush EndPoint=".7,1" StartPoint=".7,0"> <GradientStop Color="#FFFFFFFF" Offset="0"/> <GradientStop Color="#F9FFFFFF" Offset="0.375"/> <GradientStop Color="#E5FFFFFF" Offset="0.625"/> <GradientStop Color="#C6FFFFFF" Offset="1"/> </LinearGradientBrush> </Border.Background> </Border> <Rectangle Grid.ColumnSpan="4" Grid.RowSpan="1" StrokeThickness="1"> <Rectangle.Fill> <LinearGradientBrush EndPoint="0.3,-1.1" StartPoint="0.46,1.6"> <GradientStop Color="#FF4084BD"/> <GradientStop Color="#FFAFCFEA" Offset="1"/> </LinearGradientBrush> </Rectangle.Fill> <Rectangle.Stroke> <LinearGradientBrush EndPoint="0.48,-1" StartPoint="0.48,1.25"> <GradientStop Color="#FF494949"/> <GradientStop Color="#FF9F9F9F" Offset="1"/> </LinearGradientBrush> </Rectangle.Stroke> </Rectangle> <Path Grid.ColumnSpan="4" Grid.Column="0" Data="M11.426758,8.4305077 L11.749023,8.4305077 L11.749023,16.331387 L10.674805,16.331387 L10.674805,10.299648 L9.0742188,11.298672 L9.0742188,10.294277 C9.4788408,10.090176 9.9094238,9.8090878 10.365967,9.4510155 C10.82251,9.0929432 11.176106,8.7527733 11.426758,8.4305077 z M14.65086,8.4305077 L18.566387,8.4305077 L18.566387,9.3435936 L15.671368,9.3435936 L15.671368,11.255703 C15.936341,11.058764 16.27293,10.960293 16.681133,10.960293 C17.411602,10.960293 17.969301,11.178717 18.354229,11.615566 C18.739157,12.052416 18.931622,12.673672 18.931622,13.479336 C18.931622,15.452317 18.052553,16.438808 16.294415,16.438808 C15.560365,16.438808 14.951641,16.234707 14.468243,15.826504 L14.881817,14.929531 C15.368796,15.326992 15.837872,15.525723 16.289043,15.525723 C17.298809,15.525723 17.803692,14.895514 17.803692,13.635098 C17.803692,12.460618 17.305971,11.873379 16.310528,11.873379 C15.83071,11.873379 15.399232,12.079271 15.016094,12.491055 L14.65086,12.238613 z" Fill="#FF2F2F2F" HorizontalAlignment="Center" Margin="4,3,4,3" Grid.Row="1" Grid.RowSpan="3" RenderTransformOrigin="0.5,0.5" Stretch="Fill" VerticalAlignment="Center"/> <Ellipse Grid.ColumnSpan="4" Fill="#FFFFFFFF" HorizontalAlignment="Center" Height="3" StrokeThickness="0" VerticalAlignment="Center" Width="3"/> <Border x:Name="DisabledVisual" BorderBrush="#B2FFFFFF" BorderThickness="1" Grid.ColumnSpan="4" CornerRadius="0,0,.5,.5" Opacity="0" Grid.Row="0" Grid.RowSpan="4"/> </Grid> </Grid> </ControlTemplate> </Grid.Resources> <Grid.ColumnDefinitions> <ColumnDefinition Width="*"/> <ColumnDefinition Width="Auto"/> </Grid.ColumnDefinitions>  <Button x:Name="PART_Button" Grid.Column="1" Foreground="{TemplateBinding Foreground}" Focusable="False" HorizontalAlignment="Left" Margin="3,0,3,0" Grid.Row="0" VerticalAlignment="Top" Width="20"/>  <DatePickerTextBox x:Name="PART_TextBox" Grid.Column="0" Foreground="{TemplateBinding Foreground}" Focusable="{TemplateBinding Focusable}" HorizontalContentAlignment="Stretch" Grid.Row="0" VerticalContentAlignment="Stretch"/> <Grid x:Name="PART_DisabledVisual" Grid.ColumnSpan="2" Grid.Column="0" IsHitTestVisible="False" Opacity="0" Grid.Row="0"> <Grid.ColumnDefinitions> <ColumnDefinition Width="*"/> <ColumnDefinition Width="Auto"/> </Grid.ColumnDefinitions> <Rectangle Grid.Column="0" Fill="#A5FFFFFF" RadiusY="1" Grid.Row="0" RadiusX="1"/> <Rectangle Grid.Column="1" Fill="#A5FFFFFF" Height="18" Margin="3,0,3,0" RadiusY="1" Grid.Row="0" RadiusX="1" Width="19"/> <Popup x:Name="PART_Popup" AllowsTransparency="True" Placement="Bottom" PlacementTarget="{Binding ElementName=PART_TextBox}" StaysOpen="False"/> </Grid> </Grid> </Border> </ControlTemplate> </Setter.Value> </Setter> </Style> </Window.Resources> <Grid> <DatePicker Width="150" Height="26" Style="{StaticResource DatePickerStyle}"/> </Grid>中使用--network=host参数可以解决问题。

这只是一种解决方法。我将用更多信息更新这个问题。

MySQL-Docker容器和MySQL之间突然出现“通信链接失败”

1 个答案: