topic Re: IPsec tunnel takes long time to re-establish in General Topics

IPsec tunnel takes long time to re-establish

CTramier — Sun, 16 Oct 2022 06:16:22 GMT

Hello,

We have 2 IPsec tunnels s2s between 2 Palo Alto firewalls.

We are using ike-v2 gateways, and liveness check : 5s

The WAN on one of the side is flapping, sometimes disconnect around 10min. After this disconnection, the tunnel does not re-establish immediately, it takes around 15min.

We have also configured tunnel monitors on both sides, we have assigned IP addresses on tunnel interfaces, and we are monitoring these IPs, the monitor are UP and active.

Do you know why it's not reconnecting immediately after the WAN back up ? Is there something to do in terms of config ?

Re: IPsec tunnel takes long time to re-establish

CTramier — Thu, 20 Oct 2022 12:17:31 GMT

In fact, when the public IP is reachable again, we can see the tunnel is briefly re-established then go down again, and we need to bounce it manually to have it reconnected.

Re: IPsec tunnel takes long time to re-establish

ksalustro — Wed, 15 Feb 2023 18:56:16 GMT

I am seeing a similar issue that I'm trying to work through. In your setup, is there is a single WAN interface at the site, or are you failing over to another WAN interface? Is either side of the tunnel in dynamic, or passive mode?

Do you have "Liveness Check" enabled in the IKE settings?

Re: IPsec tunnel takes long time to re-establish

ksalustro — Wed, 15 Feb 2023 18:58:26 GMT

Also is there any NAT involved and if so, do you have NAT-T enabled?

Re: IPsec tunnel takes long time to re-establish

nikoolayy1 — Mon, 20 Feb 2023 10:43:43 GMT

Better enable IKE debugs and to see what is happening as to not make wild suggestions:

https://knowledgebase.paloaltonetworks.com/KCSArticleDetail?id=kA10g000000ClivCAC

https://knowledgebase.paloaltonetworks.com/KCSArticleDetail?id=kA10g000000ClcKCAS

https://knowledgebase.paloaltonetworks.com/KCSArticleDetail?id=kA10g000000PORsCAO