Electronic Arts have the worst support portal EVER!

I'm incredulous at EA's very bad support process.

I had purchased some in-app content for my son's tablet, and after an app reinstall it would not resume the content.

So I tried, repeat, tried to contact EA.

Their Contact Us portal is horrific. It is a "fake" contact us, wherein it pretends to offer you an ability to contact but in reality forces you down the check forums and raise a ticket via the portal.

But the portal was horrific.

Trying to raise a new ticket on this URL didn't work.
1. Go to https://help.ea.com/en/fifa/ea-sports-fifa/
2. Scroll down and select "Contact Us"
3. Click on Android Tablet and select Next
4. Select "Missing Content" and "Had content and lost it"
5. In the "Please tell us a little more about your issue" box type "In-App Purchases"
6. Press Next
7. You get dumped on Step 3 above. You cannot complete the support request.

Eventually I chose a different selection option and got to the end screen. But if I attached a PNG to the ticket whilst raising it - it dumped you back at the beginning.

Eventually I figured I had to raise a ticket under the wrong option and submit it. And then attach the JPG after.

During this process I was in an email conversation with a support guy who was adamant I should attach the PNG to a support ticket that he had raised of which I had no access to.

In all, this whole debacle cost me 1.5 hours of my life, to fix a problem with my son's in app purchase. It is enough to put me off in-app purchases for life!

NB: I contacted Google and they refunded it within 5 minutes. They've got the right customer experience.

Port exhaustion on Windows server

We had a set of servers that started showing what seemed to be random connection errors. They ran across services and across servers.

Our first thought was it was a hardware or centralised switch problem, but the network guys assured us the switch had no problem.

Then we started leaning towards configuration problems on the boxes. These servers ran multiple services, all heavy socket consumers.

Whenever a socket connection is made to a known port, Windows also uses a temporary socket for the return communications. These temporary sockets, known as ephemeral or short-lived sockets, are assigned from a pool which can be configured.

netsh int ipv4 show dynamicportrange tcp
Protocol tcp Dynamic Port Range
---------------------------------
Start Port      : 50001
Number of Ports : 255

This is an incredibly low number for a server high in comms. It shows that when a socket is created, only 255 are available. Bearing in mind when the communication has completed the socket remains open for a short while (known as the TcpTimedWaitDelay) for efficiency in reuse. This defaults to 30 seconds.

Also the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\Tcpip\Parameters showed  a MaxUserPort of 1279, which conflicted with the StartPort + Number of Ports range.

In a state of port exhaustion MS documentation says that you can get non-specific errors that just look like general connection errors.

e.g.
System.Net.WebException: The underlying connection was closed: An unexpected error occurred on a send.

References
https://msdn.microsoft.com/en-us/library/aa560610(v=bts.20).aspx
http://www.outsystems.com/forums/discussion/6956/how-to-tune-the-tcp-ip-stack-for-high-volume-of-web-requests/
https://technet.microsoft.com/en-us/library/cc938219.aspx

Installing gpiozero on the Raspberry Pi (Wheezy)

I found it troublesome to install the gpiozero package in order to interface to the Rasbperry PI IO.

In the end the following commands worked:

sudo apt-get update
sudo apt-get install python3-pip

sudo pip-3.2 install gpiozero

Test it with
sudo python3 -c "import gpiozero"

https://docs.google.com/document/d/1EbbVjdgXbKVPFlgH_pEEtPZ0zOZVSPHT4sQNW88Am7w/edit?pli=1#

Running the program within IDLE raised the exception about not able to access /dev/mem. To fix this I added the IDLE shortcut to the desktop, ran the nano editor under sudo to edit the shortcut and ran IDLE with the sudo prefix.

Fakes Mocks and Stubs

Fakes, Mocks and Stubs offer varying depth of business logic.

A Fake is a simple object that contains no business logic. It simply contains specific values (such as good or bad) that can be injected into a test to determine the result.

A Mock allows the test to replace a method call or property accessors to return a particular value. For example the test can mock a repository class to return pre-canned data when the Read() method is called. Mocks are also useful in unit tests as they can tested that particular methods were called and how many times they were called. You can assert against a mock.

A Stub is more comprehensive and at the coding level can replace an entire class. For the repository example the repository could be replaced with a StubRepository and this either returns a response based upon input data or based upon some preconfigured data.

Beyond the coding level a Stub can also be used to replace a subsystem. If a payments system is calling a third party interface, it may be necessary to stub out the 3rd party. This benefits if calling the third party costs money, if performance tests are required, if you want to avoid overloading the third party, or if the third party is unable to provide the failure scenarios when you need them.

For a stubbed interface it is often useful to return output data based upon input data. For a Fraud-checking stub, the response may vary based upon the applicant's last name, e.g. fail fraud checks if the last name is "MyLastName_Fail". You want to avoid statefulness in the stub or vary the response from the stub based upon configuration, which would require a system restart.

For performance testing it may also be useful to simulate latency based upon input data. In our Fraud Check example the response may delayed by 5 seconds if the applicant's first name was "MyFirstName_5s". This delay may help tease out scalability problems or race conditions in neighbouring parts of the system. The test driver can then issue a variety of load conditions simply by supplying varying usernames as request parameters.

I found my AD account being locked continuously when I had an enforced password change. This was because I had many disconnected (but not logged off) RDP sessions on many test servers across the network. So with the help of this PowerShell module, I wrote a script to detect which sessions were left open so I could manually log off.

Import-Module PSTerminalServices

$username = 'AndrewPotts'
$servers = @("serverA","serverB")

foreach ($server in $servers)
{
 Write-Host -NoNewLine $server
 
 try
 {
  $loggedOn = $False
  
  Get-TSSession -ComputerName $server | ForEach-Object { 
   if ($_.Username -eq $username) { $loggedOn = $True }
  }
  
  
  if ($loggedOn -eq $True)
  {
   Write-Host -ForegroundColor Yellow ' Logged on'
  }
  else
  {
   Write-Host
  }
 }
 catch [System.Exception]
 {
  Write-Host -ForegroundColor Red ' $_.Exception.Message'
 }
}

Debugging with WinDbg

Open a command prompt as administrator.


If you get
Cannot load "xxx"

when typing
.load clr sos

then make open a command prompt as administrator

set the path to include the .net framework 2.0 and 4.0

C:\windows\Microsoft.NET\Framework\v4.0.30319\

If it is a 32-bit process, load the 32-bit windbg and reference
the paths to the 32-bit .NET

If it is a 64-bit process, load the 32-bit windbg and reference
the paths to the 64-bit .NET, eg:
C:\windows\Microsoft.NET\Framework64\v4.0.30319\

WCF scalability settings

This article provides a good steer on the scalability settings for WCF.