topic Re: DUAL Dynamic IPSEC Tunnels single VR in General Topics

DUAL Dynamic IPSEC Tunnels single VR

mhm_ameen — Sun, 28 Aug 2022 09:38:30 GMT

Hi , have 2 dynamic isp at site 1 with single vr and ECMP and 1 public ip at site 2 paloalto at OCI cloud , i have setup dual tunnels from site 1 to site 2 but its not stable at all , both tunnels will be up but if we simulate failover using either path monitoring or tunnel monitoring or making isp 1 or 2 down we can see that vpn is stuck in initiating phase. We used below guide

https://knowledgebase.paloaltonetworks.com/KCSArticleDetail?id=kA10g000000POO0CAO

Re: DUAL Dynamic IPSEC Tunnels single VR

OtakarKlier — Mon, 29 Aug 2022 15:29:45 GMT

Hello,

What IP are you using as your monitor? Also what happens if you disable ECMP and user weighted routes instead?

Please advise,

Re: DUAL Dynamic IPSEC Tunnels single VR

mhm_ameen — Tue, 30 Aug 2022 07:07:35 GMT

using tunnels ip for monitor for IPSEC, i don't want to disable ECMP since requirements is to have load balancing internet connection. please find attached diagram.

we are using FQDN for dynamic peer in ike gateway.

FQDN being used is ip address is it ok or it must be in form of name.domain.com ??

Re: DUAL Dynamic IPSEC Tunnels single VR

OtakarKlier — Thu, 01 Sep 2022 15:53:52 GMT

Hello,

I would make sure your monitor IP's for the tunnels are only sent down the tunnel that has the monitored IP address. I think ECMP might be messing up the tunnel monitor, ie sending traffic down one tunnel and reaching the IP address so the tunnel never goes down and routing gets goofed.

So make sure the tunnel monitor is setup so tunnel 1 uses an IP address that is only accessible via tunnel 1. What I have done, since I use OSPF, is to have the tunnels have a /30 address and static routes that are only sent down that tunnel and not down OSPF.

example: Tunnel1 has a /30 IP address and the other side of the tunnel has the other /30 address. The the static route for the /30 is sent to the tunnel interface and is not redistributed via OSPF so it cant reroute.

Hope that makes sense.

Regards,