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Forum » Dynamicweb 9.0 Upgrade issues » Duplicate email sent in webfarm situation

Duplicate email sent in webfarm situation

Sean Meade Dynamicweb Employee
Sean Meade

Hi, folks

We have a customer with a webfarm. After they upgraded to 9.9.7 they started getting duplicate email reciepts sent after checkout. They finally found a hint in the logs yesterday: the message is getting sent by both nodes simultaneously.

Any idea what would cause this to occur in a webfarm situation?

Thanks, Sean


Deni Paramarta

Hey everyone,

The customer Sean is referring to is the company I work for. I am one of the web developers. The version we're running on currently is 9.12.4.





Martin Vang
Martin Vang

Hi Guys,

I was wondering about a couple of things:

1. Do you have multiple Instances/machines running dynamicweb on the webfarm (using the same Database+files)?

2. Do you use our LoadBalancingProvider? If so, what version?

3. If yes to 2, then are you using HostName or IP to identify the primary machine that should process the scheduled tasks?



Sean Meade Dynamicweb Employee
Sean Meade

Hi, Martin

1. It’s a 2 node webfarm with a shared database but separate disks which are kept in sync with a file sync service.

2. Yes. We're using the current version of the LoadBalancingProvider as far as I know. I don't have access to their /bin. Here's the screenshot they sent when I asked. Not sure if it tells you anything though:

Do you need me to get any more specific information on this from the customer?

3. The fields in the backend are (in the order of the headings below):

Hostname, DNS, DNS, IP address.


Nicolai Pedersen

I can see that the date of the providers dll is from 2018 - so what version is that?

You can see there are a number of them which are new versions here:


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