Network traffic to Management Center

I’m installing Mosquitto, Streamsheets and the Management Center through Docker. Everything works perfectly, however when I am connected to the Management Center I receive traffic on the network port, something around 14 Mbps continuously.
This traffic is considered normal for communication between the Management Center and my browser or am I wrong in some configuration.
If there are more clients connected to Mosquitto generating topics, will this traffic increase?

Hi @pedro.rc ,

Thanks for your message. Just talked to the technical colleagues: 14 Mbit would be very large as traffic in this case. Since we just entered the week-end here in Germany, it might take until Monday that we will come back to you, but I guess that this traffic has other reasons than the management center.


Hi Pedro,

Sorry for the delay getting you a proper reply. The management center (MMC) backend subscribes to the # topic on Mosquitto so that it can present a topic tree of known topics to the users browsing the MMC front end. This means that traffic on the Mosquitto instance will be duplicated to the MMC. The MMC backend also has to send data to each MMC frontend that is currently open. So if you are currently sending around 14Mbps to the broker then yes, this is an expected level of traffic. We are aware that the current implementation isn’t optimised for performance and are looking into how we can optimise this and still get the same functionality.

If the bandwidth you are sending to the broker isn’t around 14Mbps then there may be another problem we need to look into.



Hi @roger.light, thanks for replying,
I’m also using MQTT Explorer trying to understand the situation, and I noticed that the amount of updates of topics $SYS is much lower than when compared to those that are updated in the TOPIC TREE of the MMC.
I think the topics update should be the same, considering that the subscribe in $SYS is the same for both.
In this sense, every update in TOPIC TREE generates the high traffic reported.
In another test I disabled all clients, leaving only the cedalo client, and there was only 1 active connection in the broker. Even in this situation, I still have that traffic.

Just to come back to this, if you update the Management Center to at least version 2.4.2 then there is an option to disable the topic tree in the settings.



Hi, thanks for the reply.
Could you tell me what is the best way, or the correct way to proceed with this update?
I tried to do the update as follows and had the following problems:
I changed the docker-compose.yml on the line
image: cedalo/management-center:2.4.5
and after docker compose up -d.
the container was uploaded with the correct version but when accessing the management I receive the information that You have not configured any broker.
Please create the connection first.

After entering the broker credentials and trying to save I get the error
Error creating connection “My Mosquitto broker”. Reason: BaseMosquittoProxyClient: Timeout.

Hello pedro,

Do you know from which version you have updated?


Hi Tizian,
I’m trying to update from:
Name – Cedalo Management Center
Version – 2.2
Build number – 1625492115

Hi pedro,

Thank you.
Is there any error code popping up in your terminal?
If you want, you can send me a PM with your config file, so we can have a closer look. :slight_smile:


I chose to test other versions, going down one by one, and in 2.4.2 optive success. In others, I always had the same situation.
For the moment version 2.4.2 meets my need.
Follows log of version 2.4.5 that cannot connect.

Starting Management Center for Eclipse Mosquitto
No license key found or provided.
Tue, 23 Aug 2022 19:24:57 GMT express-session deprecated undefined resave option; provide resave option at start.js:175:24
Tue, 23 Aug 2022 19:24:57 GMT express-session deprecated undefined saveUninitialized option; provide saveUninitialized option at start.js:175:24
Connecting to “Mosquitto 2.0” on mqtt://mosquitto:1883
Started Mosquitto proxy at http://localhost:8088
“CEDALO_MC_PLUGIN_DIR” is not set. Skipping loading of plugins
Mosquitto proxy server started on port 8088
Connected to ‘Mosquitto 2.0’ at mqtt://mosquitto:1883
No license key found or provided.

Hi pedro,

Try adding CEDALO_MC_PLUGIN_DIR in your docker-compose file:
The value of this variable is not important, but if it’s not defined mmc won’t work properly.

      CEDALO_MC_USERNAME: myuser
      CEDALO_MC_PASSWORD: mypassword

This is mainly used for our premium plugins, but the MMC is expecting this entry anyway.

actually solved the problem by adding CEDALO_MC_PLUGIN_DIR:
thanks for the feedback.

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