Bigger

先说下环境：
CentOS7.3，当然Debian/Ubuntu也基本一致。
步骤：
1.下载二进制安装包：

wget -c 
https://fastdl.mongodb.org/linux/mongodb-linux-x86_64-3.4.0.tgz

2.解压缩：

tar -zxvf mongodb-linux-x86_64-3.4.0.tgz

3.把二进制文件放到/usr/local/mongodb下面，当然不是必须要放这里的：

cp mongodb-linux-x86_64-3.4.0 /usr/local/mongodb -f

4.设置环境变量：

# 编辑/etc/profile文件
vi /etc/profile
# 增加一条环境变量设置
export PATH=/usr/local/mongodb/bin:$PATH

5.增加mongodb启动用户：

useradd -g mongod mongod

6.创建数据库文件夹，并给mongod权限，这里给放到/data/mongo下：

mkdir -p /data/mongo
chown -R mongod:mongod /data/mongo

7.创建日志目录，并给mongod权限

mkdir -p /var/log/mongodb
chown -R mongod:mongod /var/log/mongodb

8.创建进程管理目录，并给mongod权限

mkdir -p /var/run/mongodb
chown -R mongod:mongod /var/run/mongodb

9.创建mongodb配置文件mongod.conf，并给mongod权限

vi /etc/mongod.conf
chown mongod:mongod /etc/mongod.conf

之后内容如下：

# mongod.conf
# for documentation of all options, see:
#   http://docs.mongodb.org/manual/reference/configuration-options/
# where to write logging data.
systemLog:
  destination: file
  logAppend: true
  path: /var/log/mongodb/mongod.log
# Where and how to store data.
storage:
  dbPath: /data/mongo
  journal:
    enabled: true
#  engine:
#  mmapv1:
#  wiredTiger:
# how the process runs
processManagement:
  fork: true  # fork and run in background
  pidFilePath: /var/run/mongodb/mongod.pid  # location of pidfile
# network interfaces
net:
  port: 27017
  bindIp: 127.0.0.1  # Listen to local interface only, comment to listen on all interfaces.
#security:
#operationProfiling:
#replication:
#sharding:
## Enterprise-Only Options
#auditLog:
#snmp:

保存

10.增加启动脚本，这里使用systemctl：

vi /usr/lib/systemd/system/mongod.service

内容如下：

[Unit]
Description=High-performance, schema-free document-oriented database
After=network.target
Documentation=https://docs.mongodb.org/manual
[Service]
User=mongod
Group=mongod
Environment="OPTIONS=--quiet -f /etc/mongod.conf"
ExecStart=/usr/local/mongodb/bin/mongod $OPTIONS run
PIDFile=/var/run/mongodb/mongod.pid
# file size
LimitFSIZE=infinity
# cpu time
LimitCPU=infinity
# virtual memory size
LimitAS=infinity
# open files
LimitNOFILE=64000
# processes/threads
LimitNPROC=64000
# total threads (user+kernel)
TasksMax=infinity
TasksAccounting=false
# Recommended limits for for mongod as specified in
# http://docs.mongodb.org/manual/reference/ulimit/#recommended-settings
[Install]
WantedBy=multi-user.target

保存

11.启用启动脚本

systemctl enable mongod.service

12.使用服务：

# 启动：
service mongod start
# 停止：
service mongod stop
# 重启：
service mongod restart

如果mongo命令不可用，请检查环境变量的设置；如果mongo命令报错，请查看日志/var/log/mongodb/mongod.log

13.卸载：

# 停止服务：
service mongod stop
# 删除启动脚本
rm /usr/lib/systemd/system/mongod.service -f
# 重新加载脚本
systemctl daemon-reload
# 删除配置文件
rm /etc/mongod.conf -f
# 删除日志文件夹
rm /var/log/mongodb -rf
#删除进程管理文件夹
rm /var/run/mongodb -rf
#删除安装文件
rm /usr/local/mongodb -rf
#删除数据库文件
rm /data/mongo -rf
#清除环境变量
vi /etc/profile
#删除 export PATH=/usr/local/mongodb/bin:$PATH，并保存

（完）

在ASP.NET 4.5及之前的版本，可以使用FormsAuthenticationTicket来做基础身份认证，现在到了.Net Core中，发现原来的FormsAuthenticationTicket不能用了，其实在.Net Core中，依然可以使用基础身份认证，下面是使用方法。因为这是在具体项目中使用的，会多出一些其他的代码，请自行忽略。

1.在Startup.cs文件中，public void ConfigureServices(IServiceCollection services)方法下添加：

services.AddAuthorization();

完整代码：

        public void ConfigureServices(IServiceCollection services)
        {
            // Add framework services.
            services.AddApplicationInsightsTelemetry(Configuration);
            services.AddOptions();
            services.Configure<Models.ConnectionStrings>(Configuration.GetSection("ConnectionStrings"));
            services.AddAuthorization();    //Form基础验证
            services.AddMvc();
        }

2.在public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)方法下添加：

            app.UseCookieAuthentication(new CookieAuthenticationOptions
            {
                AuthenticationScheme = "Cookie",
                LoginPath = new PathString("/Manage/Login"),
                AccessDeniedPath = new PathString("/Manage/Forbidden"),
                AutomaticAuthenticate = true,
                AutomaticChallenge = true
            });

完整代码：

        public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
        {
            loggerFactory.AddConsole(Configuration.GetSection("Logging"));
            loggerFactory.AddDebug();
            //Form基础验证
            app.UseCookieAuthentication(new CookieAuthenticationOptions
            {
                AuthenticationScheme = "Cookie",
                LoginPath = new PathString("/Manage/Login"),
                AccessDeniedPath = new PathString("/Manage/Forbidden"),
                AutomaticAuthenticate = true,
                AutomaticChallenge = true
            });
            app.UseApplicationInsightsRequestTelemetry();
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
                app.UseBrowserLink();
            }
            else
            {
                app.UseExceptionHandler("/Home/Error");
            }
            app.UseApplicationInsightsExceptionTelemetry();
            app.UseStaticFiles();
            app.UseMvc(routes =>
            {
                routes.MapRoute(
                    name: "default",
                    template: "{controller=Home}/{action=Index}/{id?}");
            });
        }

如果发现有报错，添加引用即可。

3.在控制器文件中，登录的方法下，添加：

                var claims = new List<Claim>()
                {
                    new Claim(ClaimTypes.Name,login.username) 
                    //,new Claim(ClaimTypes.Email,"emailaccount@microsoft.com")  
                };
                //var userPrincipal = new ClaimsPrincipal(new ClaimsIdentity(claims, "SuperSecureLogin"));
                var userPrincipal = new ClaimsPrincipal(new ClaimsIdentity(claims, token));
                HttpContext.Authentication.SignInAsync("Cookie", userPrincipal, new AuthenticationProperties
                {
                    ExpiresUtc = DateTime.UtcNow.AddMinutes(20),
                    IsPersistent = false,
                    AllowRefresh = false
                });

在我自己的项目中，完整的Login方法代码：

        [HttpPost]
        [ModelValidationFilter]
        public Models.ResultModel<object> Login(Models.Login login)
        {
            var result = new Models.ResultModel<object>();
            result = _manage.Login(login);            
            if(result.status)
            {//登录成功
                string token = result.data.ToString();  //登录成功后生成的token，用于验证登录有效性
                var claims = new List<Claim>()
                {
                    new Claim(ClaimTypes.Name,login.username) 
                    //,new Claim(ClaimTypes.Email,"emailaccount@microsoft.com")  
                };
                //var userPrincipal = new ClaimsPrincipal(new ClaimsIdentity(claims, "SuperSecureLogin"));
                var userPrincipal = new ClaimsPrincipal(new ClaimsIdentity(claims, token));
                HttpContext.Authentication.SignInAsync("Cookie", userPrincipal, new AuthenticationProperties
                {
                    ExpiresUtc = DateTime.UtcNow.AddMinutes(20),
                    IsPersistent = false,
                    AllowRefresh = false
                });
            }
            return result;
        }

4.在需要进行身份验证的控制器或Action上，添加[Authorize]特性，如：

加在Action上

        [Authorize]
        public IActionResult Dashboard()

或加在Controller上

    [Authorize]
    public class ManageSystemController : Controller

5.取验证信息

     var auth = await HttpContext.Authentication.GetAuthenticateInfoAsync("Cookie");
     string username = auth.Principal.Identity.Name;    //用户名

6.注销登录

    HttpContext.Authentication.SignOutAsync("Cookie");

具体可参考微软官方Demo：How to achieve a basic authorization in ASP.NET Core

1.查看当前的数据库用户连接有多少

 USE master
 GO
 --如果要指定数据库就把注释去掉
 SELECT * FROM sys.[sysprocesses] WHERE [spid]>50 --AND DB_NAME([dbid])='gposdb'
 SELECT COUNT(*) FROM [sys].[dm_exec_sessions] WHERE [session_id]>50

2.查看各项指标是否正常，是否有阻塞，选取了前10个最耗CPU时间的会话

SELECT TOP 10
[session_id],
[request_id],
[start_time] AS '开始时间',
[status] AS '状态',
[command] AS '命令',
dest.[text] AS 'sql语句', 
DB_NAME([database_id]) AS '数据库名',
[blocking_session_id] AS '正在阻塞其他会话的会话ID',
[wait_type] AS '等待资源类型',
[wait_time] AS '等待时间',
[wait_resource] AS '等待的资源',
[reads] AS '物理读次数',
[writes] AS '写次数',
[logical_reads] AS '逻辑读次数',
[row_count] AS '返回结果行数'
FROM sys.[dm_exec_requests] AS der 
CROSS APPLY 
sys.[dm_exec_sql_text](der.[sql_handle]) AS dest 
WHERE [session_id]>50 AND DB_NAME(der.[database_id])='gposdb'  
ORDER BY [cpu_time] DESC

3.查看具体的SQL语句，需要在SSMS里选择以文本格式显示结果

--在SSMS里选择以文本格式显示结果
SELECT TOP 10 
dest.[text] AS 'sql语句'
FROM sys.[dm_exec_requests] AS der 
CROSS APPLY 
sys.[dm_exec_sql_text](der.[sql_handle]) AS dest 
WHERE [session_id]>50  
ORDER BY [cpu_time] DESC

4.查看CPU数和user scheduler数和最大工作线程数，检查worker是否用完也可以排查CPU占用情况

 --查看CPU数和user scheduler数目
 SELECT cpu_count,scheduler_count FROM sys.dm_os_sys_info
 --查看最大工作线程数
 SELECT max_workers_count FROM sys.dm_os_sys_info

5.查看worker是否用完，如果达到最大线程数的时候需要检查blocking

SELECT
scheduler_address,
scheduler_id,
cpu_id,
status,
current_tasks_count,
current_workers_count,active_workers_count
FROM sys.dm_os_schedulers

对照表：
各种CPU和SQLSERVER版本组合自动配置的最大工作线程数

6.查看会话中有多少个worker在等待

 SELECT TOP 10
 [session_id],
 [request_id],
 [start_time] AS '开始时间',
 [status] AS '状态',
 [command] AS '命令',
 dest.[text] AS 'sql语句', 
 DB_NAME([database_id]) AS '数据库名',
 [blocking_session_id] AS '正在阻塞其他会话的会话ID',
 der.[wait_type] AS '等待资源类型',
 [wait_time] AS '等待时间',
 [wait_resource] AS '等待的资源',
 [dows].[waiting_tasks_count] AS '当前正在进行等待的任务数',
 [reads] AS '物理读次数',
 [writes] AS '写次数',
 [logical_reads] AS '逻辑读次数',
 [row_count] AS '返回结果行数'
 FROM sys.[dm_exec_requests] AS der 
 INNER JOIN [sys].[dm_os_wait_stats] AS dows 
 ON der.[wait_type]=[dows].[wait_type]
 CROSS APPLY 
 sys.[dm_exec_sql_text](der.[sql_handle]) AS dest 
 WHERE [session_id]>50  
 ORDER BY [cpu_time] DESC

7.查看ASYNC_NETWORK_IO等待

（注：比如我当前执行了查询SalesOrderDetail_test表100次，由于表数据非常多，所以SSMS需要把SQLSERVER执行的结果慢慢的取走，造成了ASYNC_NETWORK_IO等待）

 USE [AdventureWorks]
 GO
 SELECT * FROM dbo.[SalesOrderDetail_test]
 GO 100

8.查询CPU占用高的语句

SELECT TOP 10
   total_worker_time/execution_count AS avg_cpu_cost, plan_handle,
   execution_count,
   (SELECT SUBSTRING(text, statement_start_offset/2 + 1,
      (CASE WHEN statement_end_offset = -1
         THEN LEN(CONVERT(nvarchar(max), text)) * 2
         ELSE statement_end_offset
      END - statement_start_offset)/2)
   FROM sys.dm_exec_sql_text(sql_handle)) AS query_text
FROM sys.dm_exec_query_stats
ORDER BY [avg_cpu_cost] DESC

9.查询缺失索引

SELECT 
    DatabaseName = DB_NAME(database_id)
    ,[Number Indexes Missing] = count(*) 
FROM sys.dm_db_missing_index_details
GROUP BY DB_NAME(database_id)
ORDER BY 2 DESC;

SELECT  TOP 10 
        [Total Cost]  = ROUND(avg_total_user_cost * avg_user_impact * (user_seeks + user_scans),0) 
        , avg_user_impact
        , TableName = statement
        , [EqualityUsage] = equality_columns 
        , [InequalityUsage] = inequality_columns
        , [Include Cloumns] = included_columns
FROM        sys.dm_db_missing_index_groups g 
INNER JOIN    sys.dm_db_missing_index_group_stats s 
       ON s.group_handle = g.index_group_handle 
INNER JOIN    sys.dm_db_missing_index_details d 
       ON d.index_handle = g.index_handle
ORDER BY [Total Cost] DESC;

本文中，假定你已经安装好了Mongodb、及ASP.NET Core的开发环境。本文主要说下在ASP.NET Core中怎样连接Mongodb数据库：
一、在ASP.NET Core中使用Mongodb，首先要安装C#的Mongodb Driver，现在最新的是2.3版本，使用Nuget直接安装就可以。
二、配置数据库的连接，打开appsettings.json文件，添加下面设置：

  "ConnectionStrings": {
    "MongodbConnection": "mongodb://127.0.0.1:27017"
  }

三、新建一个关于连接数据库的Model类，我是放在Models类库中，具体可以根据自己的项目来

    public class ConnectionStrings
    {
        public string MongodbConnection { get; set; }
    }

四、打开Startup.cs文件，修改 ConfigureServices 方法，如下：

        public void ConfigureServices(IServiceCollection services)
        {
            // Add framework services.
            services.AddApplicationInsightsTelemetry(Configuration);
            services.AddOptions();    //增加
            services.Configure<IB.Models.ConnectionStrings>(Configuration.GetSection("ConnectionStrings"));    //增加数据库连接
            services.AddMvc();
        }

五、使用

        private readonly IOptions<Models.ConnectionStrings> _settings;    //取数据库连接串
        public DemoController(IOptions<Models.ConnectionStrings> settings)
        {
            this._settings = settings;
        }

以上

因为.net core我也是边学边用，会时不时的遇到些比较坑人的地方，会不定期的在这里更新，同时给出脱坑方法。目前有如下这些坑：

1.如果开发环境没有安装.Net Core 1.1，而服务器上是.Net Core 1.1的环境，那么。。。你的程序在服务器上跑不起来，向下不兼容，要问怎么解决，打开你的工程，打开nuget，更新，把里面的全都更新了，之后再重新编译部署就可以了。

2.按照官网文档https://docs.microsoft.com/en-us/aspnet/core/publishing/linuxproduction进行部署，到使用systemd来管理.net core站点启动这一步的时候，无论你怎么操作都是不会像官方那样成功的，而是会报500错误，而直接使用dotnet命令来运行的时候又没问题，使用journalctl 命令来看日志，会看到这些：

    root@biz126:/home/wwwroot/netcore/domain/tool.dwz.nz/web# journalctl -fu kestrel-dwztool.service
    -- Logs begin at Fri 2016-11-18 12:10:41 CST. --
    Nov 19 22:19:04 biz126 dotnet-tooldwznz[14275]: Application started. Press Ctrl+C to shut down.
    Nov 19 22:51:46 biz126 systemd[1]: Stopping tool.dwz.nz website...
    Nov 19 22:51:46 biz126 dotnet-tooldwznz[14275]: Application is shutting down...
    Nov 19 22:51:47 biz126 systemd[1]: Stopped tool.dwz.nz website.
    Nov 19 22:53:05 biz126 systemd[1]: Starting tool.dwz.nz website...
    Nov 19 22:53:05 biz126 systemd[1]: Started tool.dwz.nz website.
    Nov 19 22:53:06 biz126 dotnet-tooldwznz[17468]: Hosting environment: Production
    Nov 19 22:53:06 biz126 dotnet-tooldwznz[17468]: Content root path: /
    Nov 19 22:53:06 biz126 dotnet-tooldwznz[17468]: Now listening on: http://localhost:5000
    Nov 19 22:53:06 biz126 dotnet-tooldwznz[17468]: Application started. Press Ctrl+C to shut down.

从日志中的“Content root path: /”可以看到，把/文件夹作为了站点的根目录了，解决方法：打开Program.cs文件，添加using System.Reflection;，之后注释掉原来的.UseContentRoot(Directory.GetCurrentDirectory())，添加新的.UseContentRoot(Path.GetDirectoryName(Assembly.GetEntryAssembly().Location))，再重新编译发布部署，就可以了

如果要在VS中调试的话，还要再改回去。

3.如果你所有的步骤都是按照官方文档进行，安装的时候：

    sudo apt-get install curl libunwind8 gettext
    curl -sSL -o dotnet.tar.gz https://go.microsoft.com/fwlink/?LinkID=835021
    sudo mkdir -p /opt/dotnet && sudo tar zxf dotnet.tar.gz -C /opt/dotnet
    sudo ln -s /opt/dotnet/dotnet /usr/local/bin

设置守护进程：

        [Unit]
        Description=Example .NET Web API Application running on Ubuntu

        [Service]
        ExecStart=/usr/bin/dotnet /var/aspnetcore/hellomvc/hellomvc.dll
        Restart=always
        RestartSec=10                                          # Restart service after 10 seconds if dotnet service crashes
        SyslogIdentifier=dotnet-example
        User=www-data
        Environment=ASPNETCORE_ENVIRONMENT=Production 

        [Install]
        WantedBy=multi-user.target

.Net Core 2.0.7 使用的systemctl配置如下：

[Unit]
Description=Example .NET Web API App running on Ubuntu

[Service]
WorkingDirectory=/var/aspnetcore/hellomvc
ExecStart=/usr/bin/dotnet /var/aspnetcore/hellomvc/hellomvc.dll
Restart=always
RestartSec=10  # Restart service after 10 seconds if dotnet service crashes
SyslogIdentifier=dotnet-example
User=www-data
Environment=ASPNETCORE_ENVIRONMENT=Production
Environment=DOTNET_PRINT_TELEMETRY_MESSAGE=false

[Install]
WantedBy=multi-user.target

启用服务：

    systemctl enable kestrel-hellomvc.service

启动服务：

        systemctl start kestrel-hellomvc.service
        systemctl status kestrel-hellomvc.service

你会发现，真是日了卵，http://localhost:5000无法访问，查日志：

    journalctl -fu kestrel-hellomvc.service

泥煤的，果然是有问题，站点没跑起来，什么原因呢？

问题就在这里（此处应有柯南）：

安装的时候，dotnet的环境变量添加在/usr/local/bin里，而守护进程的服务设置的却是/usr/bin/dotnet，能好用才见鬼，把守护进程中的/usr/bin/dotnet换成/usr/local/bin/dotnet就好了，我也在本系列中的第一篇文章《.Net Core系列教程（一）——环境搭建》中提到过。

4.创建Web项目，之后运行，咦？不按套路出牌，默认的项目竟然直接报一大堆错，像什么

Can not find runtime target for framework '.NETCoreApp,Version=v1.0' compatible with one of the target runtimes: 'win10-x64, win81-x64, win8-x64, win7-x64'

1.The project has not been restored or restore failed - run dotnet restore

2.The project does not list one of 'win10-x64, win81-x64, win8-x64, win7-x64' in the 'runtimes' section.

3.You may be trying to publish a library, which is not supported. Use dotnet pack to distribute libraries.

而报错文件全都指向.net core的C:\Program Files (x86)\MSBuild\Microsoft\VisualStudio\v14.0\DotNet\Microsoft.DotNet.Common.Targets文件的第262行，？？？一脸黑人问号。

报的错如下图：

我可是什么也没干啊，而且这报的还不是哪个代码的错误，这是哪里出了问题呢？这个也是从1.0升级为1.1之后出现的问题，解决办法（敲黑板，划重点）：

打开项目的配置文件project.json，找到 <span style="background-color: #D8D8D8;"> "Microsoft.NETCore.App": "1.1.0</span>",，修改为：

    "Microsoft.NETCore.App": {
        "version": "1.1.0",
        "type": "platform"
    },

保存，运行，通过，哦了，搞定。