This is probably the easiest question to answer for any SQL Server DBA. And this is one of those scenarios where the adage “There are multiple ways to skin a cat” holds true. You could look into the SQL Server Errorlog and quickly look up the phrase “is listening on” and find lines of the following nature:

Server is listening on [ ‘any’ <ipv6> 1433].
Server is listening on [ ‘any’ <ipv4> 1433].

Or you could even use SQL Server Configuration Manager (SQL Server 2005 and above) to figure out the TCP/IP settings of the SQL instance. Now there is a catch here! If you see the screenshot, you will notice that the Listen All property is set to YES. This means that the SQL Server instance will listen on all the IP Addresses that the server/machine is configured to listen on. If this property was set to NO, then you moved over the IP Addresses tab (see screenshot), you would have see one of the IPs listed there which was Active and Enabled. (IP Address hidden in screenshot). All this seems simple enough, right? Then why am I taking the time to mention all these facts that you are already know and are probably questioning my sanity about writing such a post. Well…. If you had a let’s say a few hundred SQL Server instances from which you needed to fetch this information, then I can imagine how much you would relish the manual task of fetch this information. Both the options mentioned above, Errorlog and Configuration Manager, will not help you in this endeavor. Which is why I decided to leverage two of my best friends in the scripting world…. WMI and Powershell.

Using the namespace for SQL Server 2008: root\Microsoft\SqlServer\ComputerManagement10 and the class ServerNetworkProtocolProperty, you can fetch the TCP/IP settings for any SQL instance. The script illustrated below can be used to fetch the IP Address(es) that one SQL instance is listening on. You could write an outer loop to fetch the SQL Server instance names from a database or XML file and then use the script below to get the relevant data. If you want to SQL Server 2005 specific code, then the namespace to be used is root\Microsoft\SqlServer\ComputerManagement. Unfortunately for SQL Server 2000 and below, there are no WMI namespaces available to retrieve this information. In case you have SQL Server 2000 instances in your shop, then you would have to write Powershell code to fetch this information from the instance specific registry keys or using Select-String cmdlet to traverse the SQL Errorlog to retrieve this information. Note that the Errorlog approach has caveats in environments where the Errorlog is regularly recycled.

Addition: January 30, 2012: If you have specific IPs that a SQL Server failover cluster is listening on with the Listen All property set to TRUE, then the script can be modified such that only the Active and Enabled IP Addresses are reported by the script below. The part of the script which reports the IP Config output for the server can be omitted.

# This Sample Code is provided for the purpose of illustration only and is not intended to be used in a production environment. THIS SAMPLE CODE AND ANY RELATED INFORMATION ARE PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR PURPOSE. We grant You a nonexclusive, royalty-free right to use and modify the Sample Code and to reproduce and distribute the object code form of the Sample Code, provided that You agree: (i) to not use Our name, logo, or trademarks to market Your software product in which the Sample Code is embedded; (ii) to include a valid copyright notice on Your software product in which the Sample Code is embedded; and (iii) to indemnify, hold harmless, and defend Us and Our suppliers from and against any claims or lawsuits, including attorneys’ fees, that arise or result from the use or distribution of the Sample Code.
# Author: Amit Banerjee
# Description: Powershell code to fetch the IP Addresses that the SQL instance is listening on.
# Notes:
# root\Microsoft\SqlServer\ComputerManagement10 - This namespace is applicable for SQL Server 2008 and above.
# For SQL Server 2005 the namespace is root\Microsoft\SqlServer\ComputerManagement
# There is no equivalent WMI namespace for SQL Server 2000 instance

# Provide the computer name that you want to query
$vComputerName = "."
# Provide the SQL instance name that you want the information for
# MSSQLSERVER for default instance
$vInstanceName = "MSSQLSERVER"

Write-Host "IP Address(es) that the SQL instance " $vComputerName "\" $vInstanceName " is listening on are listed below: "

$vListenAll = 0
$vTCPProps = get-WMIObject ServerNetworkProtocolProperty -ComputerName $vComputerName -NameSpace "root\Microsoft\SqlServer\ComputerManagement10" | Where-Object {$_.PropertyName  -eq "ListenOnAllIPs" -and $_.InstanceName -eq $vInstanceName}
foreach ($vTCPProp in $vTCPProps)
{
$vListenAll = $vTCPProp.PropertyNumVal
}

if($vListenAll -eq 1)
{
Write-Host "Is instance configured to listen on All IPs (Listen All property): TRUE"
# Get Networking Adapter Configuration
$vIPconfig = Get-WmiObject Win32_NetworkAdapterConfiguration -ComputerName $vComputerName

# Iterate and get IP address on which the SQL is listening
foreach ($vIP in $vIPconfig)
{
if ($vIP.IPaddress)
{
foreach ($vAddr in $vIP.Ipaddress)
{
$vAddr
}
}
}
}
else
{
# If SQL is configured to listen for specific IP addresses (eg. SQL clusters), then this else block will fetch those IP Addresses
# The Sort-Object ensures that the for-each loop below doesn't break while reporting the active and enabled IPs
$vIPProps = get-WMIObject ServerNetworkProtocolProperty -ComputerName $vComputerName -NameSpace "root\Microsoft\SqlServer\ComputerManagement10" | Where-Object {$_.InstanceName -eq $vInstanceName -and $_.ProtocolName  -eq "Tcp"} | Sort-Object IPAddressName,PropertyName
$vActive = 0
$vEnabled = 0

Write-Host "Is instance configured to listen on All IPs (Listen All property): FALSE"

foreach ($vIPProp in $vIPProps)
{
# Check if the IP is active
if ($vIPProp.Name -ne "IPAll" -and ($vIPProp.PropertyName -eq "Active"))
{
$vActive =  $vIPProp.PropertyNumVal
}
# Check if the IP is enabled
if ($vIPProp.Name -ne "IPAll" -and ($vIPProp.PropertyName -eq "Enabled"))
{
$vEnabled = $vIPProp.PropertyNumVal
}
# Report the IP if active and enabled
if ($vIPProp.Name -ne "IPAll" -and $vIPProp.PropertyName -eq "IPAddress" -and $vEnabled -eq 1 -and $vActive -eq 1)
{
# Get the IP addresses that SQL is configured to listen on
$vTCPProp.PropertyStrVal
}
}
}