Volume Mapping (On-premise)
When you need to read and write files from an on-premise disk, you need to know the path in which the data is stored and make sure that the docker container in your runtime(s) running has access to this path. There are several ways of dealing with this challenge. First, this microlearning will discuss the various alternatives and best approaches in these scenarios.
Should you have any questions, please contact academy@emagiz.com.
1. Prerequisites
- Basic knowledge of the eMagiz platform
2. Key concepts
This microlearning centers around learning how to set up your volume mapping correctly so you can exchange file-based data on-premise.
By volume mapping, we mean: Creating a configuration through which the docker container can read and write data on a specific path on an on-premise machine.
There are several options for volume mapping for your on-premise machine.
- Volume
- Bind mount
- Temporary file system
- Named pipe
3. Volume Mapping (On-premise)
When you need to read and write files from an on-premise disk, you need to know the path in which the data is stored and make sure that the docker container in your runtime(s) running has access to this path. There are several ways of dealing with this challenge. First, this microlearning will discuss the various alternatives and best approaches in these scenarios.
There are several options for volume mapping for your on-premise machine.
- Volume
- Bind mount
- Temporary file system
- Named pipe
Below we will explain the differences between the various options available for your volume mapping. But before we do, we first explain how to set up this configuration within eMagiz. Then, you must navigate to Deploy -> Architecture on the model level. In this overview, you can access the Volume mapping per runtime deployed on-premise. To do so, you can right-click on the runtime to access the context menu.
When you click this option, you will see the following pop-up. In this pop-up, you can define the machine-level and runtime-level volumes. More on that later. This is the starting point for configuring your volume mapping. We will walk through each available option and explain how they work and should be configured.
3.1 Volume
The first type available to you is Volume. With this option you create one or more folders on docker that is relevant for that runtime to read and/or write persistent data. To configure this type you need to link the runtime volume to a machine volume that you can create within the same pop-up. This means that you can re-use a "Machine volume" over multiple runtimes (i.e. containers).
So, at first we open the tab called "Machine volume". By pressing the "New" button we can define a new "Machine volume". In the pop-up that follows we can define the name of a machine volume and tell whether the volume already exists on your docker installation or not.
Once you have done so we press "Save" and switch back to the "Runtime volumes" tab. In here we press the "New" button to create a new "Runtime volume". In the pop-up that follows we first need to select the Type we want to use. For this example we use the type called "Volume". Based on your selection the relevant input fields will change.
The first thing we need to select is the "Machine volume". Once we have selected our "Machine volume" we need to select the Target that is specific for this runtime. This target defines the second part of the path to which the runtime will gain access. For example, when you fill in "/target" we can combine this with the "Machine volume" name to arrive at the correct directory from which eMagiz needs to read data (or write data to). So in our case this would be "/file-directory/target."
The last setting we need to configure is to define which rights we will grant our runtime on the volume we are creating. The default setting is read/write rights for the runtime which is sufficient in most cases. The result of following these steps will be the following.
3.2 Bind mount
An alternative option to read and write persistent data is to use the "Bind mount" option avaiable. In general we advice to use the "Volume" option because they have better performance and bind mounts are dependent on the directory structure and OS of the host machine. Having said that not all external systems can adapt to this that easily. That is why the "Bind mount" option can be of interest in your use case.
To configure a "Bind mount" you need to define a source and a target directory that are linked to each other. The source directory defines the directory on your local system (that might already be in use currently to exchange files). The target directory defines a directory on your docker installation that can be accessed by the runtime.
3.3 Temporary file system
3.4 Named pipe
The named pipe option can be selected but we yet have to see a valid use case within the context of eMagiz for using this option. Therefore we won't discuss this option further in this microlearning.
4. Assignment
Configure an entry in which you build the archiving and the clean up of the archiving.
This assignment can be completed with the help of the (Academy) project that you have created/used in the previous assignment.
5. Key takeaways
- Archiving is used for audit purposes
- Archiving is used for retry scenarios
- Ensure that data is cleaned after a retention period to keep in control of the data
- Don't forget the max messages per poll
6. Suggested Additional Readings
If you are interested in this topic and want more information on it please read the help text provided by eMagiz and check out the following store content:
7. Silent demonstration video
This video demonstrates how you could have handled the assignment and gives you some context on what you have just learned.