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ASA 8.4 - RAVPN Hairpinning to subnet across S2S VPN - Routing failed to locate next hop

Hi all!

Having a weird issue trying to get my RAVPN users to access resources at a remote site(corp).  RAVPN users (192.168.11.x) can access resources at the main site, and the main site can access resources at the remote site(192.168.101.x), but when I try to setup the hairpin connection so the RAVPN users can hit the remote site, I get a weird error in the logs - "Routing failed to locate next hop for ICMP from Outside:192.168.11.x to Inside:192.168.101.x"

My thought here is that it's trying to access the remote subnet via the Inside interface as shown in the error above "Inside:192.168.101.x", as my understanding is that since that subnet is on the other end of a site to site VPN, it should be accessed via the outside interface.  

Relevant sections of crypto map on main ASA:

crypto map Outside_map 1 match address Outside_cryptomap_1

access-list Outside_cryptomap_1 extended permit ip object-group DM_INLINE_NETWORK_3 object Corp-subnet 

object-group network DM_INLINE_NETWORK_3
 network-object object VPN-network

object network VPN-network
 subnet 192.168.11.0 255.255.255.0
 description VPN Subnet

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Nat statements:
nat (Outside,Outside) source static VPN-network VPN-network destination static Corp-subnet Corp-subnet
nat (Inside,Outside) source static any any destination static VPN-network VPN-network

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Access Lists:
access-list Outside_access_in extended permit ip object VPN-network object Corp-subnet 
access-list Outside_access_in extended permit ip object Corp-subnet object VPN-network 

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Any ideas what I'm doing wrong?
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valheru_m
Asked:
valheru_m
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1 Solution
 
eeRootCommented:
Do pings or trace routes from the firewall to 192.168.101.x connect properly?  If not, what path does the trace route reveal?
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Marius GunnerudSenior Systems EngineerCommented:
I suspect that the traffic from the RAVPN is not being encrypted over the site to site vpn.  make sure the 192.168.11.x network is configured in the crypto ACL at both the corp and remote site also that there is an identity NAT / no nat statement for this traffic at both sites also.

would help to see the full sanitized configuration from both sites.
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Marius GunnerudSenior Systems EngineerCommented:
Also make sure that routing is configured for the RAVPN at the remote site
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valheru_mAuthor Commented:
eeRoot:  Ping gets no response.  Traceroute doesnt even show a first hop.
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valheru_mAuthor Commented:
Attached is the CoLo (Main site) config sanitized. Will sanitize corp and post shortly.
CoLoASA-sanitized.rtf
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valheru_mAuthor Commented:
Corp config sanitized
CorpSanitized.txt
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Marius GunnerudSenior Systems EngineerCommented:
it doesn't look like you have defined the RAVPN in the site to site cryptomap, but it is difficult to tell since a lot of the IPs are removed.  Are you using public IPs internally?

Also, The EasyVPN configuration at the corp office, I did not find a corresponding config on the remote office so I am assuming that is not being used here.

I would set up the site to site to include the 192.168.11.x network and add it to the no nat config at both ends.
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valheru_mAuthor Commented:
On the corp site, users do have the ability to RAVPN there as well, but I'm trying to get rid of that for reasons that are a little too long-winded to expand upon here.  The RAVPN config at that site will be going away.  

There are no internal public IPs.  

As for the config, the relevant lines from the config I posted that address the nonat on both ends I *think* are these, but if I'm mistaken please feel free to correct me:

crypto map outside_map 2 match address outside_cryptomap
access-list outside_cryptomap extended permit ip 192.168.101.0 255.255.255.0 object-group DM_INLINE_NETWORK_2 
object-group network DM_INLINE_NETWORK_2
 <redacted> *** note that I only redacted the IPs not involved with the VPNNet, which is the VPN subnet from the CoLo ***
 network-object VPNNet 255.255.255.0

name 192.168.11.0 VPNNet description  VPN Network

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The 192.168.101.0(Corp) and 192.168.11.0(CoLo VPN) nets are the only ones I'm concerned with at this time and everything else seems to be working fine.

On the CoLo config, I believe these are the relevant lines:

nat (any,any) source static VPN-network VPN-network destination static Corp-subnet Corp-subnet

crypto map Outside_map 1 match address Outside_cryptomap_1

access-list Outside_cryptomap_1 extended permit ip object-group DM_INLINE_NETWORK_3 object Corp-subnet 

object-group network DM_INLINE_NETWORK_3
 network-object object Dev-Network
 network-object object Prod-Network
 network-object object VPN-network

object network VPN-network
 subnet 192.168.11.0 255.255.255.0
 description VPN Subnet

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Are you reccommending modifications to these lines specifically or...?

Thanks for your time!
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Marius GunnerudSenior Systems EngineerCommented:
At the ColoASA remove the any any from the NAT statements and specify the exact subnets.  Something like the following

nat (Outside,Outside) source static VPN-network VPN-network destination static Corp-subnet Corp-subnet
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