public void setMultipleServerConnectionsAllowed(boolean allowed) {
        JiveGlobals.setProperty("xmpp.server.session.allowmultiple", Boolean.toString(allowed));
        if (allowed && JiveGlobals.getIntProperty("xmpp.server.session.idle", 10 * 60 * 1000) <= 0)
        {
            Log.warn("Allowing multiple S2S connections for each domain, without setting a " +
                    "maximum idle timeout for these connections, is unrecommended! Either " +
                    "set xmpp.server.session.allowmultiple to 'false' or change " +
                    "xmpp.server.session.idle to a (large) positive value.");
        }
    }
Sets if remote servers are allowed to have more than one connection to this
server. Having more than one connection may improve number of packets that can be
transfered per second. This setting only used by the server dialback mehod.<p>

It is highly recommended that {@link #getServerSessionTimeout()} is enabled so that
dead connections to this server can be easily discarded.

@param allowed true if remote servers are allowed to have more than one connection to this
       server.
xmppserver/src/main/java/org/jivesoftware/openfire/SessionManager.java