SQLServer Redirector Port 1434

[Byrocat]

I'm doing some vulnerability assessments of MS SQLServer installations
using AppDetective.

On doing the "discovery" proble (to find the instances), I find that I
get two "hits" -- port 1433 shows the MS SQALServer instance, but port
1434 comes up with MS SQL Server Redirector.

The online books seems to be a bit light on waht the use of this port
is for.

I thought that port 1433 was the port on which SQLServer listens for
ODBC connections.

However, port 1434 seems to be used for the same purpose.

Any additional information of a non-technical level (my manager needs
to know this and he's not a DBA) is greatly appreciated.

Thanks in advance!

[Erland Sommarskog]

Byrocat (bd******@sympatico.ca) writes:

I'm doing some vulnerability assessments of MS SQLServer installations
using AppDetective.

On doing the "discovery" proble (to find the instances), I find that I
get two "hits" -- port 1433 shows the MS SQALServer instance, but port
1434 comes up with MS SQL Server Redirector.

The online books seems to be a bit light on waht the use of this port
is for.

I thought that port 1433 was the port on which SQLServer listens for
ODBC connections.

However, port 1434 seems to be used for the same purpose.

Any additional information of a non-technical level (my manager needs
to know this and he's not a DBA) is greatly appreciated.

1434 is the port used to find named instances. Say that you need to
connect to MACHINE\INSTANCE2. The client first asks on 1434 where to
find INSTANCE2, and then gets the correct port number to use. If you
close this port, clients will have to specify the port number when
connecting to named instances.

The same thing applies if you move the default instance from 1433 to
some other port.
--
Erland Sommarskog, SQL Server MVP, es****@sommarskog.se

Books Online for SQL Server SP3 at
http://www.microsoft.com/sql/techinf...2000/books.asp