Non-Meraki VPN - IKEv2 issues (?)

[RaphaelL]

Hi ,

I would like to start off by stating that I'm a complete noob when it comes to VPN , IPSEC , SA , IKEv2 and all that stuff.

We have a simple setup. One MX peering to a Palo Alto. 

Phase 1 works fine and Phase 2 works fine.... most of the time. 

As you can see ( even if it's blured ) there are like 10 subnets configured. 

When we establish the tunnel , ALL 10 subnets are working fine. After couple hours ( something like 6-24 hours ). Some of the subnets stop working. 

I can see the log on the MX that : msg: <remote-peer-2|13> closing CHILD_SA net-2{42} with SPIs cccdb01e(inbound) (54640 bytes) 9812d7e5(outbound) (144750 bytes) and TS XXXXXXXX/28 === XX.XX.15.0/24

However when ever I try to bring the SA up by sending traffic to .15.0/24 it doesn't. Either I have to bring to whole tunnel down and up OR I can bring it up by sending traffic from the Palo-Alto side. 

I have confirmed that the timers of Phase 1 and 2 are matching on both sides ( 28800s and 3600s )

I'm running MX18.211.3 and I have a case open.

I have read the multiple posts here and many of the documentation pages but I couldn't find anything except : https://documentation.meraki.com/MX/Site-to-site_VPN/Site-to-Site_VPN_Settings#NOTE_For_IKEv2

Any troubleshooting ideas ?

Cheers , 

[KarstenI]

The Link you posted and here with some more details:

https://documentation.meraki.com/MX/Site-to-site_VPN/IKEv1_and_IKEv2_for_non-Meraki_VPN_Peers_Compar...

The IKEv2 implementation of the MX is different to approx. 90% of commercial firewalls out there.  It's a shame that the MX team doesn't care. Or they care in a way that they hope customers move the peer to AutoVPN. Sadly, for me, some customers moved entirely away from the Meraki Fullstack because of MX limitations.

[RaphaelL]

That's sad. I just hope that Support is going to tell me right away that this is not working instead of me wasting hours trying to tshoot that. 

I didn't design that. Our Extranet is built with Palo Alto and I can't easily put a MX HUB. That would solve all my issues in an instant , but not possible atm.

[AgungTP]

hmm, I'm having the same issue here.. I need to reset the tunnel from the other side (the initiator) to make it works, re-enable the VPN tunnel or restart MX didn't help at all

[CJHarms]

We seem to have exactly the same Problem. I also have a Case open (12167713) but no Fix/Workaround so far.

We remove and re-add the Network Tag on the affected Site-to-Site VPN Peer to get it going again for 24-48hrs.

[AgungTP]

well, I have decided to use IKEv1 instead of IKEv2, I have no choice currently, its running stable so far (at least for the last 2 weeks)

[CJHarms]

We might also need to go back to IKEv1. In the new MX19.x Firmware i can see a lot of Bugfixes regarding Third Party VPNs - I hope the Fixes get backported to the MX18.x Firmware so I can try if a new 18.x Firmware fixes the IKEv2 Problems.