Meraki MX100 SIP and Dual WAN

New here

Meraki MX100 SIP and Dual WAN

I have a situation where I am implementing a cloud based SIP phone system with all my users behind and MX100 configured with dual WAN.  I have the MX configured to send all traffic out WAN 1, but continue to see phone traffic traversing WAN 2.  I have my traffic shaping policies set to give priority to all SIP traffic, and my question is, would my traffic shaping override the "send all traffic out WAN 1" statement, and look at the available bandwidth of both WANs combined?  Or would it only look at the available bandwidth of WAN 1?



5 Replies 5
Meraki Employee
Meraki Employee

Hi @12ax7,


Can you explain a little more of your setup? global setting is set to use WAN1 as primary uplink and using shaping for VoIP priority?

This far traffic should not be affected to use a different uplink. 

Do you have load balancing enabled?

Just browsing



Seen the same for SMTP.   Support couldn't find why this was happening.  Running on beta on this MX now,  still sometimes it goes to the wrong WAN.

Kind of a big deal
Kind of a big deal

I have seen something similar happen when there is a momentary outage on the primary circuit.  The MX keeps sending flows out the backup circuit until those flows end before moving them back.  The problem is some flows are long lived and can take a very long time to failback.


I've found causing a failure on the back path (such as unplugging the backup circuit and plugging it back in again) forces everything back onto the primary circuit.

Indeed, same seems to happen with 4G failover,   unplugging works fine,  but no internet connection takes way longer to be detected, or not at all sometimes.  

Yep, you need the physical interface to be brought down.  Otherwise you need to wait five or so minutes for the logic to switch over.

Get notified when there are additional replies to this discussion.
Welcome to the Meraki Community!
To start contributing, simply sign in with your Cisco account. If you don't yet have a Cisco account, you can sign up.