LSVPN not working when NAtted via Loopback

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LSVPN not working when NAtted via Loopback

Hi Community,

 

I got the following problem:

We have a running LSVPN with primary and secondary tunnel, which are connected on the hub on two different VRs, which sync themselves via iBGP - everything fine so far.

 

One of the satellite sites got two ISP lines, which should be used active/passive for redundancy.

Binding the IPSec tunnel on the physical interface is not possible, because when this link goes down (because provider got a problem or sth else), the down-interface won't try to establish a VPN - I need to use a loopback IP, which is natted and routed to the active ISP line.

 

I did it, and the first impression was, that this is working, BUT: After 1h, when the IPSec SA dies, the renegotiation is taking too long and the users got problems via VoIP, SAP and so on.

When checking the hub and GW firewall, I noticed, that the SSL connection to Portal was built up from Satellite to Hub (as expected), but the IPSec tunnel was built up from Hub to Satellite.

That's why I'm confused - here I'm in the position of doing the NAT myself and both providers are direct public IPs, the PAN can use, but this wouldn't work, when sitting behind a provider Internet box, which does the Natting for me.

 

Does anybody know, if it's even supported, to have the LSVPN satellite IPsec sitting on a loopback interface and using an active/passive Internet redundancy?

 

I'm happy for any inputs here.

 

Regards

Chacko

Best Regards
Chacko

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TAC confirmed:

This request is not possible with LSVPN.

When trying to achive ISP redundancy on satellite side, a workaround would be a parallel classical VPN tunnel with different metrics.

 

A feature request was created for this:

FR ID 12468

Best Regards
Chacko

View solution in original post


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could you please share rough sketch.

SD-WAN | Cloud Networking | PCNSE | ICSI CNSS | MCNA | | CCNP | CCSA | SPSP | SPSX | F5-101 | CCIE-SEC-Attempted
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Chacko42_0-1596018814080.png

That's the setup.

Default Route is with metric 10 to ISP-A with Path-Monitoring, Default-Route with metric 20 is to next vr vr-secondary.

Loopback.1 is the source interface for lsvpn ipsec tunnel.

 

When configuring the ipsec tunnel directly on ethernet1/1 without nat - tunnel works.

When configuring the ipsec tunnel on loopback with static-nat to ISP-A, the Portal connection is initiated via Satellite, but the IPSec is initiated via Hub

Best Regards
Chacko
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how do you check in lsvpn if hub is intiator ?

SD-WAN | Cloud Networking | PCNSE | ICSI CNSS | MCNA | | CCNP | CCSA | SPSP | SPSX | F5-101 | CCIE-SEC-Attempted
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when I have a look at the session table on the sateliite, I can see an outgoing session via SSL to LSVPN-Portal.

But the IPSec tunnel is incoming with source of the LSVPN-GW and that cannot be right.

 

In this special case, I can do a static nat, but if this is an ISP box with dynamic ip and we are just a box behind it, incoming IPSec is not possible and not by LSVPN design.

Best Regards
Chacko
Highlighted
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TAC confirmed:

This request is not possible with LSVPN.

When trying to achive ISP redundancy on satellite side, a workaround would be a parallel classical VPN tunnel with different metrics.

 

A feature request was created for this:

FR ID 12468

Best Regards
Chacko

View solution in original post

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