For SQL Server 2005, SQL Server 2008 and later, to get a list of SQL Server servers on the network, the sqlcmd.exe utility can be used. The sqlcmd utility lets you enter Transact-SQL statements, system procedures and script files at the command prompt. One of the arguments that can be passed to the sqlcmd utility is “-Lc” which will list locally configured server computers, and the names of the server computers that are broadcasting on the network. The “c” part of the “-Lc” argument stands for clean output and it means that the output appears without the Servers: header line and each server line is listed without leading spaces.
C:\> sqlcmd -Lc
For SQL Server 2000, the isql or osql utilities can be used. Just like the sqlcmd utility, the isql and osql utilites allow you to enter Transact-SQL statements, system procedures and script files form the command prompt. The osql utility uses ODBC to communicate with the server while the isql utility uses DB-Library to communicate with SQL Server 2000. Unlike the sqlcmd utility, the clean output “c” argument option is not available and only the “-L” command argument is available.
C:\> osql -L