Save the changes and restart the MySQL service for the changes to take effect. The next step is to create a new user for your slave server. Use the following command to create it:. Now that you have marked the position, you can start moving the data from the master to the slave. You need to create a MySQL dump file to move the data. Use the following command to create the dump file:. Now, all you need to do is configure the slave server and test if replication is working.
Ensure MySQL is installed. Open the configuration file in your slave server and update these lines:. In the same way that you did for the master server, you need to bind the IP address and uncomment those two lines for the slave server. Now, restart the MySQL server using the following command:.
Once the data is imported, you need to stop MySQL in the slave server using the following command:. You have finally imported the dump files and updated the master IP address, password, log file name, and position, to enable the master to communicate with the slave without any issues. To test if your MySQL master slave replication works, just create a database in your master server and see if it is replicated in the slave server. If you can see the database in the slave, then it is working fine.
The above article has provided you with enough information about how to set up a MySQL master slave replication. The step-by-step guide is specially provided to help beginners understand the process and start testing the replication process in their environment.
But this process requires extensive hard work as you have to manually configure many details. So, if you want to overlook this hardship and experience a hassle-free process, then give Hevo a try. Hevo is a No-code Data Pipeline. It is a fully automated platform, and so it will take over the configuration process from you. It can easily migrate your data from MySQL to your desired destination in minutes.
If you have existing data on your master that you want to synchronize on your slaves before starting the replication process, you must stop processing statements on the master.
Before permitting the master to continue executing statements, obtain its current binary log coordinates and dump its data. If you do not stop the execution of statements, the data dump and the master status information that you use will not match and you will end up with inconsistent or corrupted databases on the slaves. You will need this information when configuring the slave so that the slave knows where within the binary log to start executing events. The File column shows the name of the log file and the Position shows the position within the file.
For example, the binary log file would look like mysql-bin. Record these values. Note: If the master has been running previously without binary logging enabled, the log file name and position values will be empty. Once the data dump has been completed, you can then import this data into the slave before starting the replication process. This dumps all databases to a file named dbdump.
Dump without locking tables will not result in downtime. Once a slave is replicating, you can find in its data directory one file named master. Do not remove or edit these files unless you know exactly what you are doing and fully understand the implications. For a detailed explanation of exactly what all of the different tags here mean, please read through the Profile Developer Toolkit Guide available on the Tech Forum.
In this document, you will find definitions of everything used here. I am using BLE to communicate from multiple sensor to one central master which handle all the data.
I would also like to create an Android App that will communicate with this central master to display all the data coming from the sensor.
What would be the proper architecture? Can the central be both server and client or should I use the write functionnality to display data on my android App? What if I would like to use the app to configure my Central device with the read functionnality?
Knowledge Article. Details Details. Quick Overview Here's what this article covers: Master or " central " devices scan for other devices. Slave or " peripheral " devices advertise and wait for connections. Usually, the master is also the client. Server devices have a local database and access control methods, and provide resources to the remote client. Usually, the slave is also the server.
You can use read , write , notify , or indicate operations to move data between the client and the server. Read and write operations are requested by the client and the server responds or acknowledges. Notify and indicate operations are enabled by the client but initiated by the server, providing a way to push data to the client. Notifications are un acknowledged, while indications are acknowledged.
Notifications are therefore faster, but less reliable Example gatt. Master vs. Slave - Connection Roles One important concept in BLE connectivity is the difference between a master device and a slave device. Client vs. Receive vs. GATT structure A GATT database implements one or more profiles , and each profile is made up of one or more services , and each service is made up of one or more characteristics.
Attributes and Characteristics You may occasionally hear or see the terms "attribute" and "characteristic" used interchangeably, and while this isn't entirely wrong, it isn't totally accurate and it can be confusing.
Here are a few general guidelines about what kind of data transfer you will need to use: If the client needs to send data to the server, use write. If the client needs to get data from the server on-demand i. If the server needs to send data to the client without the client requesting it first, use notify or indicate.
The client must subscribe to these updates before any data will be transferred. The server cannot pull data from the client directly. If this is necessary, the server must use notify or indicate to send pre-arranged request data to the client, and then the client may follow up with a write operation to send back whatever data that the server needs.
Commands which you must send are shown separately from the events which the stack generates: Read - this operation is requested by the GATT client on a specific attribute exposed by the GATT server, and the server then responds with the requested value.
This can be used to read attributes up to 22 bytes in length. This is the most common method used by a GATT client to read individual attribute values. If you are building a GATT client device for a specific kind of application, you may never need this. This only applies if you are reading attributes that are longer than 22 bytes.
It is often simpler to construct your GATT server such that there are no long attributes, for simplicity. Note that the BLE protocol still requires that data is packetized into max.
This takes a list of attribute handles for input and requests all of the resulting values back at once in a single response packet. Values are sent back in the order they are requested, with no delineation between different values. Any data beyond the maximum read packet size 22 bytes will be silently dropped. This also requires that all requested attributes except optionally the last one have a known size, since no value delineation is used, and that all values combined fit within 22 bytes or less.
This event will occur exactly once for the entire "read multiple" request, delivering a maximum of 22 bytes. Normally, this operation is handled by the stack automatically, and the characteristic value stored in RAM right on the module is sent back to the client. But with "user" characteristics, this data storage and retrieval is entirely up to you.
The stack simply lets you know when it has been requested, and then you must get it or generate it , then send it back or not in whatever format is desired. This command takes a result code and the actual value, if any, to send back. The server then stores the new value and optionally acknowledges the write operation back to the client. This performs an acknowledged write operation, so the server will respond when the value has been successfully written.
This is the most common method used by a GATT client to write individual attribute values. This event is useful for controlling program flow based on whether a critical write operation has finished yet or not. This is exactly the same as the above command except that it is unacknowledged.
There will be no response upon completion. Like the "notify" operation, this means that it is faster multiple unacknowledged writes may be performed within a single connection interval , but less reliable than acknowledged writes.
It is effectively the same as a single write operation, but not executed immediately. You can queue only up to 18 bytes at a time to be written, and you specify the offset as well as the data.
This only necessary when you need to write more than 20 bytes to a single attribute, since it gives you the ability to write at a certain offset. You have to break up the write operation into byte or smaller chunks.
The stack handles sending the queued writes in multiple packets automatically when you run this command, and it will take as many connection intervals as necessary.
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