ActiveMQ warning: Frame size of 1 GB larger than max allowed 100 MB

Question

I'm trying to switch from a legacy jms broker to ActiveMQ.

One thing I cannot figure out is a warning in the logs once per hour:

WARN | Transport Connection to: tcp://127.0.0.1:38542 failed: java.io.IOException: 
  Frame size of 1 GB larger than max allowed 100 MB | ...

It's obviously some scheduled job in ActiveMQ that outputs this warning, because it comes at the same minute every hour, regardless of whether any messages are sent or not.

But what exactly means "Frame size" here?

We are not sending any jms-messages larger than a few kilobytes or so...

I read you can increase this "maxFramesize" in the connector, but doesn't help either.

When I try set it to 1GB (1073741824) (or higher) :

<transportConnector name="openwire" 
  uri="tcp://0.0.0.0:61616?maximumConnections=100&amp;wireFormat.maxFrameSize=1073741824"/>

I still see the (now absurd) warning-message:

WARN  | Transport Connection to: tcp://127.0.0.1:42256 failed: java.io.IOException: 
  Frame size of 1 GB larger than max allowed 1 GB

What is ActiveMQ actually complaining about?

And how can I fix it?

Answer 1

ActiveMQ 5 would only log this message if someone was sending your broker a message that is encoded to a size larger than the configured limit. Since it happens to you on a regular interval then I'd look for some external resource that is doing something silly like trying to telnet into the broker Openwire port to check liveness and sending some garbage string or some such. The broker would not be logging that error unless something was inbound so you need to start looking for the source of the errant sender.