Question

How to configure SQL Server to access only by dot symbol as server name

<add connectionString="Server=.;Database=aspnetdb;User ID=ccadbuser;Password=123456" name="LocalSqlServer" providerName="System.Data.SqlClient" />

Answer 1

If you mean – that you want to accept connections ONLY from local machine – then disable network protocols tcp and netpipe in sql server configuration utility. Leave only shared memory

If you insist on dot – make it programmatically, like this in c#

var csb = new SqlConnectionStringBuilder(YourConnString);
csb.DataSource = ".";

var c = new SqlConnection(csb.ToString());

do all you need