Increasing max-connection limit of your PubSub+ broker

Training, Tips and Tricks
1

Every PubSub+ broker instance has a max connection limit that can be configured. If you are using the Standard Edition, this limit is capped at 1000 connections. While there are many usecases where you don’t need to change your connection count, to be able to use Solace’s powerful event mesh capability, you need to set your max connection count to at least 1000. If your max connection count is not 1000, you will get this error when you try to create an event mesh:
 

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Verifying your max connection limit

You can verify your max connection limit via CLI. In my case, it is currently set to 100.

ip-172-31-21-24> show system

System Uptime: 40d 23h 23m 51s
Last Restart Reason: Unknown reason

Available Resources:
   CPU cores: 2
   System Memory: 8.0 GiBytes
Scaling:
   Max Connections: 100
Topic Routing:
   Subscription Exceptions: Enabled
   Subscription Exceptions Defer: Enabled

Increasing your max connections limit

To increase max connections limit to 1000, follow these steps:

ip-172-31-21-24> enable
ip-172-31-21-24# configure
ip-172-31-21-24(configure)# service msg-backbone shutdown
All clients will be disconnected.
Do you want to continue (y/n)? y

ip-172-31-21-24(configure)# hardware message-spool shutdown
All message spooling will be stopped.
Do you want to continue (y/n)? y

ip-172-31-21-24(configure)# system scaling max-connections 1000
This command causes a reload of the system.
Do you want to continue (y/n)? y

Moving ADB messages to disk  : 100%
Backing up ADB config to disk: 100%

Performing database consolidation

This will shut down your broker so you will need to restart it. You will need to bring your msg-backbone and message-spool back up. To do that, run these commands:

ip-172-31-21-24> enable
ip-172-31-21-24# configure
ip-172-31-21-24(configure)# No hardware message-spool shutdown
ip-172-31-21-24(configure)# No service msg-backbone shutdown

Verifying your new max connections limit

Run show system command to verify that the max-connections limit is set to 1000.

ip-172-31-21-24(configure)# show system

System Uptime: 0d 0h 4m 34s
Last Restart Reason: User request

Available Resources:
   CPU cores: 2
   System Memory: 8.0 GiBytes
Scaling:
   Max Connections: 1000

That’s it! Now you can go back to your Solace Admin Portal and set up Event Mesh!