[rabbitmq-discuss] BIGIP/F5 and Connection resets

Wed Dec 19 17:23:56 GMT 2012

Hi,

On 19/12/12 16:39, Jason McIntosh wrote:
> I saw that heartbeats are turned on with 3.0.0 - the question is does
> 2.8.7 have heartbeat support by default on the server side or can it be
> turned on?

Yes, heartbeat support has been available for several years. Any broker
version released in last few years will honour heartbeat requests from
clients.

The broker can propose a configured  heartbeat interval since v3.0.0
using the "heartbeat" directive:
http://www.rabbitmq.com/configure.html

The default in v3.x.x is 600 seconds. In earlier versions of the broker
the default was not to use heartbeats.

The client and broker negotiate a heartbeat interval during connection
tuning phase of connection establishment as per the specification:

http://www.rabbitmq.com/amqp-0-9-1-reference.html#connection.tune.heartbeat
http://www.rabbitmq.com/amqp-0-9-1-reference.html#connection.tune-ok.heartbeat

> How is this different the SO_KEEPALIVE: 
> http://www.erlang.org/doc/man/inet.html

The difference is that TCP keep-alives are implemented in the network
stack below the application level. They are part of the transport and
transparent to the application.

This can be turned on using the tcp_listen_options configuration
directive. The default is not to use keep-alives. Bear in mind that the
default keep-alive interval varies widely across different
implementations of TCP/IP.

> If we used just a router and not a load balancer it seems most
> network firewalls auto disconnect with NO notification both clients
> after an hour of no TCP/IP traffic

AMQP heartbeats should solve this problem.

-Emile