SD-WAN Rule Assistance

[SK2505]

Team,

We have a requirement for shift the traffic without session drop, Kindly assist us for the same.

Below are the requirement,

1.We have a VC Device (Polycom) making a outgoing calls (Not Incoming calls).

2.Have Two ISP's and configured the SD-WAN Rule also to load balance the traffic, But, the problem is, when one of the ISP went down the traffic shifted to another ISP and the existing sessions got closed and traffic initiated as new.

3.Is there any possibilities to configure SD-WAN Rule or anything without old session close?

Kindly assist 

[akristof]

Hello,

This depends on single thing. Are you using SNAT? And to what IP address you are natting your traffic? If you have your own ip address range that you are announcing to both ISPs, then it will work.

But if you are snating traffic to different IPs, this is expected behavior. Because if source-ip will change, usually server will drop the connection because it doesn't know to which session (on server) it belongs.

Also, you will need to enable this setting:

https://community.fortinet.com/t5/FortiGate/Technical-Tip-Using-SNAT-route-change-to-update-existing...

[SK2505]

Yeah, I understood. Thanks for your help

[AEK]

If you mean for IPsec VPN continuity via SD-WAN then as per my knowledge it should be possible. However I don't think this can be possible for normal internet connections.

At a given time a given remote server has a connection with your clients from IP 1.1.1.1, once you fail-over to second ISP the remote server can't just accept to resume the connections from your second IP 2.2.2.2. That's why all connection have to reset and connect again.

However

[SK2505]

Yeah, I understood. Thanks for your help