Nikki's Lunch

We had a good working application which connect to Amazon Aurora Serverless pretty well and just recently it started to intermittently unable to connect with the error "The provider did not return a ProviderManifestToken string". The following is some spec of the application: .NET Framework 4.6.2 MySQL.Data 6.10.9 MySQL.Data.Entity 6.10.9 EntityFramework 6.2.0 (EF6) When I debugged the application, it has inner exception which has the message: "Sequence contains more than one matching element". Upon more troubleshooting, I remember that Aurora Serverless is a cluster and it requires at least 2 subnets which reside in 2 different Available Zones. Amazon does not recommend the use of IP address instead provide us with an endpoint to connect to the cluster. That means, the endpoint might resolve to two IP addresses. So, I decided to see what DNS lookup will show and indeed, the endpoint resolves to two IP addresses. Hence, my suspect is the MySQLConnection w...

When I first used OpenVPN client, it was set up for me so I'm missing out on some configuration know how. And now I need to set up OpenVPN on a new computer and I need to save a connection so I can quickly connect to it the next time I log on. In this case, I'm using a v2.x.x OpenVPN client and I can't seem to figure out how to do that. It turns out that I have to be disconnected from all connections and then select Import > From server.... Then I can enter my connection information and it will be saved and easily accessible just by hovering over it and select Connect...

Environment variables can sometimes be a pain to deal with. Since environment variables are often cached or loaded only once, a change might not be immediately reflected in the application that we intend to apply them to.  In my case, I need to debug our ASP.NET application and need the new environment variables.  Restarting the Visual Studio itself was not enough.  I tried to kill the worker process and that doesn't help either.  At the end, I tried one thing that works which I got from a forum, i.e., enter the following command on command prompt or PowerShell run in admin mode: iisreset

This might affect other hosting too, but it just happened that I bumped into it in my A2 hosting account. Basically I created a new website and upload the files. I had the domain name servers updated. Everything looks good. But for somewhat reason, my default page is not shown by default. I checked the DNS propagations and it was done. I try visiting one of the pages in my website and it works great. But somehow when entering only the domain name, it doesn't bring up the default page. After several hours, I figured out that there is index.html that was put when the directory was setup. Renaming it to something other than list of default documents fix the issue.