How to have different log types using Serilog and ElasticSearch

Just use another overload for the Elasticsearch sink:

var path = GetLogPath();
var logger = new LoggerConfiguration()
    .MinimumLevel.Information()
    .Enrich.WithMachineName()
    .Enrich.WithProperty("RequestId", Guid.NewGuid())
    .WriteTo.RollingFile(
        pathFormat: path,
        outputTemplate: "{Timestamp:yyyy-MM-dd HH:mm:ss} [{Level:u4}] [{RequestId}] {Message}{NewLine}{Exception}", buffered: false, shared: true);
logger.WriteTo.Elasticsearch(
        this.configurationService.ElasticSearchUrl(), typeName: "type");

so you don't have to specify the typeName in the appsettings and it also won't affect all instances.

Updated Answer

To add Properties and values to your logger, you can use Contextual logging and Enrichment

Contextual Logger

The simplest and most direct way to attach contextual properties to a log event

First initialized your logger:

Log.Logger = new LoggerConfiguration().ReadFrom.AppSettings().CreateLogger();

Then you can create your contextual logger:

// adding Log Context
var StudentLogger = Log.Logger.ForContext<Student>();

StudentLogger.Error(/* log message */);

Or you can use correlation log entries:

// correlation Log Entries
var orderId = "some value";
var corrLog = Log.Logger.ForContext("orderId", orderId)

corrLog.Error(/* log message */);

Enrichment

In some cases we would like every event created by a logger to carry the same, fixed, property value. The Application example is one of these.

Serilog provides Enrich.WithProperty() at the level of a LoggerConfiguration for this:

Log.Logger = new LoggerConfiguration()
    .Enrich.WithProperty("Application", "e-Commerce")
    .Enrich.WithProperty("Environment", ConfigurationManager.AppSettings["Environment"])
    // Other logger configuration

---

Original Answer

There are two ways to configure Serilog:

Using API (need serilog.sinks.elasticsearch package):

var loggerConfig = new LoggerConfiguration()
    .MinimumLevel.Debug()
    .WriteTo.Elasticsearch(new ElasticsearchSinkOptions(new Uri("http://localhost:9200") ){
         AutoRegisterTemplate = true,
 });
var logger = loggerConfig.CreateLogger();

Serilog Documentation

Using configuration from AppSettings (need Serilog.Settings.AppSettings in addition to serilog.sinks.elasticsearch)

This way, you put all of your setting in AppSetting file, e.g.

<appSettings>
    <add key="serilog:using" value="Serilog.Sinks.Elasticsearch"/>
    <add key="serilog:write-to:Elasticsearch.nodeUris" value="http://localhost:9200;http://remotehost:9200"/>
    <add key="serilog:write-to:Elasticsearch.indexFormat" value="custom-index-{0:yyyy.MM}"/>
    <add key="serilog:write-to:Elasticsearch.templateName" value="myCustomTemplate"/>
  </appSettings>

And tell serilog to read the config from appSettigns

Log.Logger = new LoggerConfiguration()
  .ReadFrom.AppSettings()
  ... // Other configuration here, then
  .CreateLogger()

See: AppSetting and ElasticSearch Configure Sink

I am not sure which log event type you are referring to? In my case, I pass the object type while logging the errors:

catch (Exception ex)
{
    Logger.Error(ex, string.Format("Exception occured in Controller: {0}, Action: Post.", this.GetType()), this.GetType());