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bettioool
New Contributor II

Connection from VLAN to VIP does not work

Hello everyone,
I am in the following configuration. I have 3 VLANs (which will grow in the future) which host servers offering services (1 per VLAN).

These Servers have configured a VIP One to One, and on the policy an IP Pool with the same IP as the VIP.

If I try to connect from the various servers in these VLANs to the servers' VIP, it does not work.
For example from Server 11 I try to connect to the VIP of Server 21 or 31, the connection does not work

How can I solve this? I attach for simplicity a diagram showing the current configuration.

 

Immagine 2024-05-13 121901.png

These the policy configured for VLAN

 

 

config firewall vip
    edit "VIP Libraesva XXXX"
        set uuid b4f0161e-ea9b-51ee-e7ea-5c6c30663786
        set extip X.X.X.103
        set mappedip "10.X.21.X"
        set extintf "any"
        set color 8
    next
end

config firewall ippool
    edit "IP Pool Libraesva XXX"
        set startip X.X.X.103
        set endip X.X.X.103
    next
end

config firewall policy
    edit 44
        set name "Internet to VIP XXXX Esva HTTPS"
        set uuid 4e622af2-ecfa-51ee-d4d2-7074d2965dca
        set srcintf "virtual-wan-link"
        set dstintf "VLAN-54"
        set action accept
        set srcaddr "all"
        set dstaddr "VIP Libraesva XXXX"
        set schedule "always"
        set service "HTTPS"
        set utm-status enable
        set ssl-ssh-profile "certificate-inspection"
        set av-profile "g-default"
        set webfilter-profile "g-default"
        set ips-sensor "g-default"
        set application-list "g-default"
        set logtraffic all
    next
end

config firewall policy
    edit 35
        set name "XXXX Esva to Internet"
        set uuid 306ab010-ea9c-51ee-db4f-01ba73aaf031
        set srcintf "VLAN-54"
        set dstintf "virtual-wan-link"
        set action accept
        set srcaddr "VLAN 54 - XXXX Libraesva"
        set dstaddr "all"
        set schedule "always"
        set service "ALL"
        set utm-status enable
        set ssl-ssh-profile "certificate-inspection"
        set av-profile "g-default"
        set webfilter-profile "g-default"
        set ips-sensor "g-default"
        set application-list "g-default"
        set logtraffic all
        set nat enable
        set ippool enable
        set poolname "IP Pool Libraesva XXXX"
    next
end

 

 Thanks

Regards

10 REPLIES 10
ozkanaltas
Valued Contributor III

Hello @bettioool ,

 

Are you sure that you did enough configuration on the firewall policy? 

 

Can you share these command's output with us? After running these commands, can yo try to access your server? 

 

diagnose debug disable
diagnose debug flow trace stop
diagnose debug flow filter clear
diagnose debug reset

diagnose debug flow filter saddr  <SRC_IP>
diagnose debug flow filter daddr <DST_IP>
diagnose debug flow show console enable
diagnose debug console timestamp enable
diagnose debug flow trace start 100
diagnose debug enable

 

 

 

If you have found a solution, please like and accept it to make it easily accessible to others.
NSE 4-5-6-7 OT Sec - ENT FW
If you have found a solution, please like and accept it to make it easily accessible to others.NSE 4-5-6-7 OT Sec - ENT FW
bettioool

Hi @ozkanaltas ,

here the output of the commands:

 

id=20085 trace_id=1 func=print_pkt_detail line=5955 msg="vd-h-services:0 received a packet(proto=1, 10.127.22.101:5->209.227.211.X:2048) tun_id=0.0.0.0 from VLAN-22. type=8, code=0, id=5, seq=85."
id=20085 trace_id=1 func=init_ip_session_common line=6135 msg="allocate a new session-00144d20, tun_id=0.0.0.0"
id=20085 trace_id=1 func=get_new_addr line=1227 msg="find DNAT: IP-10.127.54.101, port-0(fixed port)"
id=20085 trace_id=1 func=fw_pre_route_handler line=182 msg="VIP-10.127.54.101:5, outdev-unknown"
id=20085 trace_id=1 func=__ip_session_run_tuple line=3560 msg="DNAT 209.227.211.X:8->10.127.54.101:5"
id=20085 trace_id=1 func=__vf_ip_route_input_rcu line=1999 msg="find a route: flag=00000000 gw-0.0.0.0 via VLAN-54"
id=20085 trace_id=1 func=fw_forward_handler line=726 msg="Denied by forward policy check (policy 0)"
id=20085 trace_id=2 func=print_pkt_detail line=5955 msg="vd-h-services:0 received a packet(proto=1, 10.127.22.101:5->209.227.211.X:2048) tun_id=0.0.0.0 from VLAN-22. type=8, code=0, id=5, seq=86."
id=20085 trace_id=2 func=init_ip_session_common line=6135 msg="allocate a new session-00144d37, tun_id=0.0.0.0"
id=20085 trace_id=2 func=get_new_addr line=1227 msg="find DNAT: IP-10.127.54.101, port-0(fixed port)"
id=20085 trace_id=2 func=fw_pre_route_handler line=182 msg="VIP-10.127.54.101:5, outdev-unknown"
id=20085 trace_id=2 func=__ip_session_run_tuple line=3560 msg="DNAT 209.227.211.X:8->10.127.54.101:5"
id=20085 trace_id=2 func=__vf_ip_route_input_rcu line=1999 msg="find a route: flag=00000000 gw-0.0.0.0 via VLAN-54"
id=20085 trace_id=2 func=fw_forward_handler line=726 msg="Denied by forward policy check (policy 0)"
id=20085 trace_id=3 func=print_pkt_detail line=5955 msg="vd-h-services:0 received a packet(proto=1, 10.127.22.101:5->209.227.211.X:2048) tun_id=0.0.0.0 from VLAN-22. type=8, code=0, id=5, seq=87."

It seems that Fortinet passes traffic through the VLAN and not through the SD-WAN zone.

In view of upcoming activities, it is inconvenient for me to make N policies for all possible connection combinations between VLANs. And with each addition of VLAN add all N possible combinations.

I would like outgoing traffic from VLAN 22 (which will have to go to VLAN 54) for example to exit and re-enter from the SD-WAN interface and not from the VLAN interface

I hope I have explained myself

Thanks
Regards

bettioool

Hi @ozkanaltas ,

here the output of command

id=20085 trace_id=1 func=print_pkt_detail line=5955 msg="vd-h-services:0 received a packet(proto=1, 10.127.X.X:5->209.227.X.X:2048) tun_id=0.0.0.0 from VLAN-XX. type=8, code=0, id=5, seq=85."
id=20085 trace_id=1 func=init_ip_session_common line=6135 msg="allocate a new session-00144d20, tun_id=0.0.0.0"
id=20085 trace_id=1 func=get_new_addr line=1227 msg="find DNAT: IP-10.127.X.X, port-0(fixed port)"
id=20085 trace_id=1 func=fw_pre_route_handler line=182 msg="VIP-10.127.X.X:5, outdev-unknown"
id=20085 trace_id=1 func=__ip_session_run_tuple line=3560 msg="DNAT 209.X.X.X:8->10.127.X.X:5"
id=20085 trace_id=1 func=__vf_ip_route_input_rcu line=1999 msg="find a route: flag=00000000 gw-0.0.0.0 via VLAN-YY"
id=20085 trace_id=1 func=fw_forward_handler line=726 msg="Denied by forward policy check (policy 0)"
id=20085 trace_id=2 func=print_pkt_detail line=5955 msg="vd-h-services:0 received a packet(proto=1, 10.127.X.X:5->209.227.X.X:2048) tun_id=0.0.0.0 from VLAN-XX. type=8, code=0, id=5, seq=86."
id=20085 trace_id=2 func=init_ip_session_common line=6135 msg="allocate a new session-00144d37, tun_id=0.0.0.0"
id=20085 trace_id=2 func=get_new_addr line=1227 msg="find DNAT: IP-10.127.X.X, port-0(fixed port)"
id=20085 trace_id=2 func=fw_pre_route_handler line=182 msg="VIP-10.127.X.X:5, outdev-unknown"
id=20085 trace_id=2 func=__ip_session_run_tuple line=3560 msg="DNAT 209.227.X.X:8->10.127.X.X:5"

It seems that Forti passes traffic through the VLAN and not through the SD-WAN zone.

In view of upcoming activities, it is inconvenient for me to make N policies for all possible connection combinations between VLANs. And with each addition of VLAN add all N possible combinations.

I would like outgoing traffic from VLAN 22 (which will have to go to VLAN 54) for example to exit and re-enter from the SD-WAN interface and not from the VLAN interface

I hope I have explained myself

Thanks

Regars

ozkanaltas
Valued Contributor III

Hello @bettioool ,

 

I understand your concern. But you can't achieve your request with your infrastructure. 

 

Because all networks are directly connected to your FortiGate. Because of that, FortiGate prefers a directly connected connection instead of SD-Wan. This is normal.

 

If you want all traffic to go to the internet and then come back from the internet, you can use vdom for this request. But this way things will get even more complicated.

If you have found a solution, please like and accept it to make it easily accessible to others.
NSE 4-5-6-7 OT Sec - ENT FW
If you have found a solution, please like and accept it to make it easily accessible to others.NSE 4-5-6-7 OT Sec - ENT FW
AEK
SuperUser
SuperUser

Hello

I see only firewall policy allowing from WAN to the VIP and from the server to WAN. Did you add a firewall policy to allow the traffic from VLAN 11 to the VIP?

AEK
AEK
bettioool
New Contributor II

Hi @AEK ,
no I did not, as it would be inconvenient with the increasing number of VLANs to make the N rules to allow all other VLANs.

Is there any way to make it work without doing these N rules?

 

Thanks


Regards

ozkanaltas
Valued Contributor III

Hello @bettioool ,

 

In normal time you need to create rule for every communication. But if can enable multiple interface policies on feature select menu. You can select multiple interface on one rule. You can solve your problem with one rule. 

If you have found a solution, please like and accept it to make it easily accessible to others.
NSE 4-5-6-7 OT Sec - ENT FW
If you have found a solution, please like and accept it to make it easily accessible to others.NSE 4-5-6-7 OT Sec - ENT FW
bettioool

Hi,
However, I need the traffic to arrive at the destination server with IP Pools (IP Public) assigned.

ozkanaltas
Valued Contributor III

Hello @bettioool ,

 

I couldn't think of this situation. In this case, you should write rules for each traffic.

If you have found a solution, please like and accept it to make it easily accessible to others.
NSE 4-5-6-7 OT Sec - ENT FW
If you have found a solution, please like and accept it to make it easily accessible to others.NSE 4-5-6-7 OT Sec - ENT FW
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