IPSec tunnel over IPSec tunnel not working

Adrian_Jensen — Thu, 06 Mar 2025 00:08:26 GMT

Has anyone ever done tunnel-over-tunnel on the PaloAlto (to Cisco/etc.)? I have been having problems getting traffic to return to a remote site. I normally have multiple IPSec tunnels to remote sites (carrying specific isolated VLAN/networks) over a private WLAN, the tunnels tied to specific Network Zones on the PaloAlto. Recently I had to setup a new remote site with a public internet connection and IPSec back to the PaloAlto public interface.

I had no problem passing generic traffic over the public IPSec tunnel. The inner IPSec tunnel establishes and sends isolated traffic to the PA, no problem. Everything goes through the Security Policies/NAT without issue. The logs show return traffic back to the remote site over the appropriate inner IPSec tunnel... But the inner tunnel traffic never arrives at the remote site... I finally found the following KB from 2019 that says due to a previous looping issue in misconfigured setups, IPSec-over-IPSec traffic is dropped internally (apparently only outbound, not inbound).

https://knowledgebase.paloaltonetworks.com/KCSArticleDetail?id=kA10g000000PLoyCAG

Is there a way around this? Would running an IP-IP tunnel over the IPSec tunnel work?

topic IPSec tunnel over IPSec tunnel not working in General Topics

IPSec tunnel over IPSec tunnel not working