Receiving Alarm "The Hub *** has too many active subscribers. You should consider to offload some of the subscribers to another Hub."

Document ID : KB000034326
Last Modified Date : 14/02/2018
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Issue: 

Receiving alarm "The Hub *** has too many active subscribers. You should consider to offload some of the subscribers to another Hub."

You may also see slow alarm throughput, frequent queue disconnects and intermittent connectivity issues.

Environment:  

 Any Windows environment with Hub 7.x and above.

Cause:  

This is due to a limitation within the OpenSSL library on Windows.

The Windows hub has a max of 64 subscribers. When the limit is exceeded you should see an alarm: "The Hub <hubname> has too many active subscribers (###). You should consider to offload some of the subscribers to another Hub."

Note that the below items are subscribers in Unified Infrastructure Manager (UIM):

    Get/Attach Queues
    Tunnels

Resolution:

The recommendation to resolve this issue is to off-load these to a "sibling" Unix hub. Unix systems do not have this limitation. You can also change the Get/Attach queues to POST and this will not count towards the subscriber limit.

Additional Information:

How Configure Queues and Tunnels