Getting Role Instance endpoint information from within an Azure VM

In a previous post I discussed the concepts of VM to VM communication in Azure.  The basics of how it works and where the knobs are to enable it.

Here is a little different focus.  It is the scenario that the endpoints have been defined, but your setup script that is installing or configuring your application needs to discover other roles and information about them because it needs to talk to them.

This is IPv4 traffic.  Most any application should know how to use this. 

I mentioned previously that name resolution is not available.  The other caveat is that I am not using Azure Connect (the Azure Virtual Network feature).  Connect gives name resolution, but it only gives me the IPv6 endpoint of the Connect VPN tunnel it does not give me the IP actual network IP addresses that my application wants.

So, PowerShell to the rescue.  To get you started I have this little PowerShell script that walks through my service, all Roles, and documents the endpoints that are enabled.

I run this on Instance A and I know where the open ports are configured on instance B.  I also use this to document my environment from within my environment by directing the output to a text file.

By the way, this is made possible by the Azure Service Runtime.  This is installed in VM Role VMs when the Windows Azure Integration Components are installed.  The hitch is that the VM must be in Azure for it to work, and you must be executing as Administrator.

<#
.SYNOPSIS
    A script to query the Azure Service Runtime and dump the endpoint configuration
    of all roles to a TXT file.
.DESCRIPTION
    This script is designed as a very simple troubleshooting tool for your VMs in Azure.
    It performs the very simple task of working through all Roles and Instances and
    writing the EndPoint configurations to a TXT file.
    This way when you are troubleshooting issues you have a quick document in the VM
    that you can reference to see what Internal EndPoints have been opened to
    facilitate VM to VM communication.
.LEGAL
    SCRIPT PROVIDED "AS IS" WITH NO WARRANTIES OR GUARANTEES OF ANY KIND, INCLUDING BUT NOT LIMITED TO
    MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR PURPOSE.  ALL RISKS OF DAMAGE REMAINS WITH THE USER, EVEN IF THE AUTHOR,
    SUPPLIER OR DISTRIBUTOR HAS BEEN ADVISED OF THE POSSIBILITY OF ANY SUCH DAMAGE.  IF YOUR STATE DOES NOT PERMIT THE COMPLETE
    LIMITATION OF LIABILITY, THEN DELETE THIS FILE SINCE YOU ARE NOW PROHIBITED TO HAVE IT.  TEST ON NON-PRODUCTION SERVERS.
.AUTHOR
    Brian Ehlert, Citrix Labs, Redmond, WA, USA
.REFERENCES
    Thank you TechNet. For examples.
#>

# declare the DumpInstance Function
function DumpInstance {
    param ($roleMem)
   
    foreach ($roleIn in $roleMem) {
    $i = ($roleIn.InstanceEndpoints.Count -  1)
    $roleIn.Role.Name + ", " + $roleIn.Id

    do {
    $keyName = $roleIn.InstanceEndpoints.Keys[$i]
    $endProtocol = $roleIn.InstanceEndpoints.Values[$i].Protocol
    $endPort = $roleIn.InstanceEndpoints.Values[$i].IPEndPoint.Port
    $endIp = $roleIn.InstanceEndpoints.Values[$i].IPEndPoint.Address.ToString()
    $endFamily = $roleIn.InstanceEndpoints.Values[$i].IPEndPoint.AddressFamily
   
    $endIp + ", " + $endPort + ", " + $keyName + ", " + $endProtocol + ", " + $endFamily
    --$i
    }
    until ($i -lt 0)
    ""
    }
}

# Add the Service Runtime snap-in to the standard Windows PowerShell command shell.
add-pssnapin microsoft.windowsazure.serviceruntime

# Get all Roles
$allRoles = Get-RoleInstance

foreach ($roleMem in $allRoles) {
    DumpInstance $roleMem
}