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Cisco Firepower 1010 Threat Defense icmp vpn communication problem

oelagy
Level 1
Level 1

Hello,


I have a problem with VPN communication from another end, they do not reach my local network in any way, I can reach the remote network at the other end. the VPN is up, can someone give me a hand.

thank you very much

35 Replies 35

@oelagy do you have the correct Access Control rules to allow the remote network to communicate with your network? Provide screenshots of your configuration.

Run packet-tracer from the CLI to simulate the traffic flow and provide the output for review.

I assume you already have NAT exemption rules in place to ensure the traffic is not unintentially translated.

 

Hello,

It happens to me with all the vpn that I have created: Attached capture of the ACLs:

oelagy_1-1681978853692.png

 

I am performing NAT

172.31.1.27 remote ip

192.100.9.95 local net

10.77.158.95 local net Nat

I attach the capture of nat

oelagy_2-1681979518284.png

Thank you

 

 

@oelagy the problem appears to be NAT, traffic is matching the dynamic NAT rule and being translated behind the FTD's outside interface.

Your NAT rules #1 and #2 should be disabled/deleted and recreated as Auto NAT rules.

I assume NAT rules #3 and #4 are correct.

Once the new Auto NAT rules (natting used for internet access) are created they will be processed after the Manual NAT rules, so VPN traffic would match the Manual NAT rules and not translated. All other traffic not matching the Manual NAT rules would subsequently match the Auto NAT rules.

oelagy
Level 1
Level 1


Hi,

I have disabled rule no. 1 and no. 2, on the other hand the rules that I have created by nate work correctly, from my network to the other end I reach all the hosts correctly


nat (inside_2,outside) source static |s2sAclSrcNwgV4|69b97ff6-cecf-11ed-8541-e3fc0f181972 |s2sAclSrcNwgV4|69b97ff6-cecf-11ed-8541-e3fc0f181972 destination static |s2sAclDestNwgV4|69b97ff6-cecf-11ed-8541-e3fc0f181972 |s2sAclDestNwgV4|69b97ff6-cecf-11ed-8541-e3fc0f181972 no-proxy-arp route-lookup
nat (inside_2,outside) source static |s2sAclSrcNwgV4|481533f2-cf91-11ed-8541-4bca6c5a3746 |s2sAclSrcNwgV4|481533f2-cf91-11ed-8541-4bca6c5a3746 destination static |s2sAclDestNwgV4|481533f2-cf91-11ed-8541-4bca6c5a3746 |s2sAclDestNwgV4|481533f2-cf91-11ed-8541-4bca6c5a3746 no-proxy-arp route-lookup
nat (inside_2,outside) source static |s2sAclSrcNwgV4|c8e6567b-d37b-11ed-8541-017d7fee41c6 |s2sAclSrcNwgV4|c8e6567b-d37b-11ed-8541-017d7fee41c6 destination static |s2sAclDestNwgV4|c8e6567b-d37b-11ed-8541-017d7fee41c6 |s2sAclDestNwgV4|c8e6567b-d37b-11ed-8541-017d7fee41c6 no-proxy-arp route-lookup
nat (inside_4,outside) source dynamic any-ipv4 interface inactive
nat (inside_3,outside) source dynamic any-ipv4 interface inactive
nat (inside_2,outside) source static local_net local_net_nat_telrad destination static remote_net_telrad remote_net_telrad
nat (inside_2,outside) source static local_net local_net_nat_ingesa destination static remote_net_ingesa remote_net_ingesa
!
object network any-ipv4
nat (inside_2,outside) dynamic interface


When you mean to create a new rule, do I have to create it for Inside2 ?


Thank you

below is need after inactive the NAT dynamic 

object network any-ipv4
nat (inside_3,outside) dynamic interface

object network any-ipv4
nat (inside_4,outside) dynamic interface

@oelagy this is an example of a NAT Exemption rule, which is a Manual NAT rule, this ensures VPN traffic is not translated. This NAT rule is above the Auto NAT rule, which is used for internet access.

RobIngram_0-1681983640630.png

You need to create these rules to match your environment, for as many interfaces as you have.

I have created this rule, attached capture

oelagy_0-1681984555354.png

@oelagy ok, that looks like it should work for networks behind interface inside_2, did you test this?

You'd need to replicate the rules for the other inside interfaces (if required).

Probamos y no funciona, no se me eestoy explicando yo puedo acceder a todas los host que tengo en otros extremos del tunel , pero desde otro extremo no pueden acceder, ni tienen comunicacion .

he probado montando otro equipo igual de la misma carcateristicas Firepower1010 y en este caso ni puedo enviar ping ni tampoco recibo en ambos exteremos

I see your early post you already config it ACL for INbound

oelagy
Level 1
Level 1

yes correct for dynamic NAT I have configured inside_2

object network any-ipv4
nat (inside_2,outside) dynamic interface

interface Ethernet1/2
nameif inside_2
cts manual
propagate sgt preserve-untag
policy static sgt disabled trusted
security-level 0
ip address 192.100.9.1 255.255.255.0

again check this POINT please 
you have thee IN interface 

INside_2
INside_3
INside_4

the INside_2 have VPN so it need two NAT (static& dynamic) if you want host also to reach internet 

INside_3/INside_4 need dynamic NAT only since it dont have VPN 

oelagy
Level 1
Level 1

I correctly reach another host that is at the other end of the tunnel, the problem is that the other end does not communicate with my network in any way.
the VPN is up and working correctly

@oelagy have you tried again since changing the NAT rules? Because in your packet-tracer output we can determine it was unintentially translated behind the outside interface.

object network any-ipv4
nat (inside_2,outside) dynamic interface