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UDP port 1434
I was just wondering if it was possible to setup remote access to 2 SQL Server database located on 2 different machines (different IP) on a network? I currently have 1 SQL Server 2000 running on a server. Our router redirects the assigned port for my instance and the UDP port 1434 to that server. With this setup i can remotely work from home on the database. Now we have another server running SQL Server 2005. I can assign that instance a different port and have it redirected to the 2nd server. But what about the UDP port 1434??? How can i share that port, or change it on either server so i can access both machines remotely? Thanks,XiNull
FYi, SQL Server Browser starts and claims UDP port 1434. When SQL Server 2000 and SQL Server 2005 clients request SQL Server resources, the client network library sends a UDP message to the server using port 1434. SQL Server Browser responds with the TCP/IP port or named pipe of the requested instance. Therefore, you need to make sure SQL Browser is enabled and started when remote client ask for which tcp port or pipe name SQL Server is listening on. If your remote SQL Instance is a default instance, you do not necessary enable sql browser since client would always try default TCP port 1433 and pipe name \<remoterserver>pipesqlquery. But, if you have SQL 2k5 named instance installed or SQL 2000 and SQL 2k5 side by side installed, you must enable and start sqlbrowser. Satya SKJ
Microsoft SQL Server MVP
Writer, Contributing Editor & Moderator
http://www.SQL-Server-Performance.Com
This posting is provided AS IS with no rights for the sake of knowledge sharing. The greatest discovery of my generation is that a human being can alter his life by altering his attitudes of mind.
I have noticed even SQL Browser service is running you may need use port number in your connection…
Is it a bug or something else? MohammedU.
Moderator
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BRowser works on the dynamic port if it is not specified, for this reason it is better to provide the port number.
BOL specifies
quote:
When an instance of SQL Server starts, if the TCP/IP or VIA protocols are enabled for SQL Server, the server is assigned a TCP/IP port. If the named pipes protocol is enabled, SQL Server listens on a specific named pipe. This port, or "pipe," is used by that specific instance to exchange data with client applications. During installation, TCP port 1433 and pipe sqlquery are assigned to the default instance, but those can be changed later by the server administrator using SQL Server Configuration Manager. Because only one instance of SQL Server can use a port or pipe, different port numbers and pipe names are assigned for named instances, including SQL Server Express. By default, when enabled, both named instances and SQL Server Express are configured to use dynamic ports, that is, an available port is assigned when SQL Server starts. If you want, a specific port can be assigned to an instance of SQL Server. When connecting, clients can specify a specific port; but if the port is dynamically assigned, the port number can change anytime SQL Server is restarted, so the correct port number is unknown to the client. Upon startup, SQL Server Browser starts and claims UDP port 1434. SQL Server Browser reads the registry, identifies all instances of SQL Server on the computer, and notes the ports and named pipes that they use. When a server has two or more network cards, SQL Server Browser returns the first enabled port it encounters for SQL Server. SQL Server 2005 and SQL Server Browser support ipv6 and ipv4. When SQL Server 2000 and SQL Server 2005 clients request SQL Server resources, the client network library sends a UDP message to the server using port 1434. SQL Server Browser responds with the TCP/IP port or named pipe of the requested instance. The network library on the client application then completes the connection by sending a request to the server using the port or named pipe of the desired instance.
When an instance of SQL Server starts, if the TCP/IP or VIA protocols are enabled for SQL Server, the server is assigned a TCP/IP port. If the named pipes protocol is enabled, SQL Server listens on a specific named pipe. This port, or "pipe," is used by that specific instance to exchange data with client applications. During installation, TCP port 1433 and pipe sqlquery are assigned to the default instance, but those can be changed later by the server administrator using SQL Server Configuration Manager. Because only one instance of SQL Server can use a port or pipe, different port numbers and pipe names are assigned for named instances, including SQL Server Express. By default, when enabled, both named instances and SQL Server Express are configured to use dynamic ports, that is, an available port is assigned when SQL Server starts. If you want, a specific port can be assigned to an instance of SQL Server. When connecting, clients can specify a specific port; but if the port is dynamically assigned, the port number can change anytime SQL Server is restarted, so the correct port number is unknown to the client. Upon startup, SQL Server Browser starts and claims UDP port 1434. SQL Server Browser reads the registry, identifies all instances of SQL Server on the computer, and notes the ports and named pipes that they use. When a server has two or more network cards, SQL Server Browser returns the first enabled port it encounters for SQL Server. SQL Server 2005 and SQL Server Browser support ipv6 and ipv4. When SQL Server 2000 and SQL Server 2005 clients request SQL Server resources, the client network library sends a UDP message to the server using port 1434. SQL Server Browser responds with the TCP/IP port or named pipe of the requested instance. The network library on the client application then completes the connection by sending a request to the server using the port or named pipe of the desired instance.
Satya SKJ
Microsoft SQL Server MVP
Writer, Contributing Editor & Moderator
http://www.SQL-Server-Performance.Com
This posting is provided AS IS with no rights for the sake of knowledge sharing. The greatest discovery of my generation is that a human being can alter his life by altering his attitudes of mind.
hmm,<br /><br />Thanks for replying…either i’m not thinking straight and don’t understand, or i explained incorrectly my problem.<br /><br />I know SQL Server Browser claims UDP port 1434. In SQL Server 2000 it was integrated within the SQL Server service itself. And I know that each instance of SQL server uses a TCP port (default is 1433). Personally i always change this port for security reason. I understand all this. <br /><br />But that’s not problem. I have 2 different machines (both having different IPs), both running SQL Servers (one is 2000, the other 2005). And I want to be able to access both these servers remotely via the internet. Both these machines are behind a router. This is NOT 2 SQL Server installed Side-by-Side, it’s 2 SQL Server installed on 2 different machines on a network. I know i can assign both of these servers (Instances) different TCP port assignments. But i can’t assign the UDP port 1434. This one seems to be locked in. So my router can only route UDP port 1434 to 1 server. So i’m stuck only being able to access 1 server.<br /><br />I hope this explanation was easier to understand <img src=’/community/emoticons/emotion-7.gif’ alt=’:S’ /><br /><br />XiNull
XiNull, I think there is something fundamentally wrong in the way that the security has been setup by your network administrators.
The port 1434 should be open for UDP traffic and should not be routed to a specific IP address. The control of access to respective servers should be controlled via rules, which should allow your remote IP address to access your VPN over specific ports (UDP 1434, TCP xxxx(whatever your sqlserver ip addresses are) etc.. UDP requests should not be routed to specific IP addresses as this is fundamentally why access to SQLServers are restricted to just one server. Olu Adedeji
True and it is better to check whether tha tport is enabled or open for traffic, if you are running any anti-virus or firewall based software it will be blocked by default. Satya SKJ
Microsoft SQL Server MVP
Writer, Contributing Editor & Moderator
http://www.SQL-Server-Performance.Com
This posting is provided AS IS with no rights for the sake of knowledge sharing. The greatest discovery of my generation is that a human being can alter his life by altering his attitudes of mind.
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