IPsec VPN

Adding source and destination subnets to IPsec VPN phase 2 configurations

If your FortiGate-7000 configuration includes IPsec VPNs you should enhance your IPsec VPN Phase 2 configurations as described in this section. If your FortiGate-7000 does not include IPsec VPNs you can proceed with a normal firmware upgrade.

Because the FortiGate-7000 only allows 16-bit to 32-bit routes, you must add one or more destination subnets to your IPsec VPN phase 2 configuration for FortiGate-7000 v5.4.5 using the following command:

config vpn ipsec phase2-interface edit “to_fgt2″So set phase1name <name> set src-subnet <IP> <netmask> set dst-subnet <IP> <netmask>

end Where

src-subnet is the subnet protected by the FortiGate that you are configuring and from which users connect to the destination subnet. Configuring the source subnet is optional but recommended.

dst-subnet is the destination subnet behind the remote IPsec VPN endpoint. Configuring the destination subnet is required.

You can add the source and destination subnets either before or after upgrading to v5.4.5 as these settings are compatible with both v5.4.3 and v5.4.5. However, if you make these changes after upgrading, your IPsec VPNs may not work correctly until these configuration changes are made.

Example basic IPsec VPN Phase 2 configuration

In a simple configuration such as the one below with an IPsec VPN between two remote subnets you can just add the subnets to the phase 2 configuration.

Enter the following command to add the source and destination subnets to the FortiGate-7000 IPsec VPN Phase 2 configuration.

config vpn ipsec phase2-interface edit “to_fgt2″So set phase1name “to_fgt2”

set src-subnet 172.16.1.0 255.255.255.0

Adding source and destination subnets to IPsec VPN phase 2 configurations

set dst-subnet 172.16.2.0 255.255.255.0

end

Example multiple subnet IPsec VPN Phase 2 configuration

In a more complex configuration, such as the one below with a total of 5 subnets you still need to add all of the subnets to the Phase 2 configuration. In this case you can create a firewall address for each subnet and the addresses to address groups and add the address groups to the Phase 2 configuration.

Enter the following commands to create firewall addresses for each subnet.

config firewall address edit “local_subnet_1” set subnet 4.2.1.0 255.255.255.0

next

edit “local_subnet_2” set subnet 4.2.2.0 255.255.255.0

next edit “remote_subnet_3”

set subnet 4.2.3.0 255.255.255.0

next edit “remote_subnet_4”

set subnet 4.2.4.0 255.255.255.0

next edit “remote_subnet_5”

set subnet 4.2.5.0 255.255.255.0 end

And then put the five firewall addresses into two firewall address groups.

config firewall addrgrp edit “local_group” set member “local_subnet_1” “local_subnet_2”

next

edit “remote_group” set member “remote_subnet_3” “remote_subnet_4” “remote_subnet_5”

end

Now, use the firewall address groups in the Phase 2 configuration:

Configuring the FortiGate-7000 as a dialup IPsec VPN server

config vpn ipsec phase2-interface edit “to-fgt2” set phase1name “to-fgt2” set src-addr-type name set dst-addr-type name set src-name “local_group” set dst-name “remote_group”

end

Configuring the FortiGate-7000 as a dialup IPsec VPN server

FortiGate-7000s running v5.4.5 can be configured as dialup IPsec VPN servers.

Example dialup IPsec VPN configuration

The following shows how to setup a dialup IPsec VPN configuration where the FortiGate-7000 acts as a dialup IPsec VPN server.

To configure the FortiGate-7000 as a dialup IPsec VPN server:

Configure the phase1, set type to dynamic.

config vpn ipsec phase1-interface edit dialup-server set type dynamic set interface “v0020” set peertype any set psksecret < password>

end

Configure the phase 2, to support dialup IPsec VPN, set the destination subnet to 0.0.0.0 0.0.0.0.

config vpn ipsec phase2-interface edit dialup-server set phase1name dialup-server set src-subnet 4.2.0.0 255.255.0.0 set dst-subnet 0.0.0.0 0.0.0.0 end

Troubleshooting

To configure the remote FortiGate as a dialup IPsec VPN client

The dialup IPsec VPN client should advertise its local subnet(s) using the phase 2 src-subnet option.

If there are multiple local subnets create a phase 2 for each one. Each phase 2 only advertises one local subnet to the dialup IPsec VPN server. If more than one local subnet is added to the phase 2, only the first one is advertised to the server.

Dialup client configuration:

config vpn ipsec phase1-interface edit “to-fgt7k” set interface “v0020” set peertype any set remote-gw 1.2.0.1 set psksecret <password>

end

config vpn ipsec phase2-interface edit “to-fgt7k” set phase1name “to-fgt7k” set src-subnet 4.2.6.0 255.255.255.0 set dst-subnet 4.2.0.0 255.255.0.0

next edit “to-fgt7k-2” set phase1name “to-fgt7k” set src-subnet 4.2.7.0 255.255.255.0 set dst-subnet 4.2.0.0 255.255.0.0

end

Troubleshooting

Use the following commands to verify that IPsec VPN sessions are up and running.

Use the diagnose load-balance status command from the primary FIM interface module to determine the primary FPM processor module. For FortiGate-7000 HA, run this command from the primary FortiGate-7000. The third line of the command output shows which FPM is operating as the primary FPM.

diagnose load-balance status

FIM01: FIM04E3E16000074

Master FPM Blade: slot-4

Slot 3: FPM20E3E17900113

Status:Working    Function:Active

Link:      Base: Up          Fabric: Up

Heartbeat: Management: Good    Data: Good

Status Message:”Running”

Slot 4: FPM20E3E16800033

Status:Working    Function:Active

Link:      Base: Up          Fabric: Up

Heartbeat: Management: Good    Data: Good

Status Message:”Running”

Troubleshooting

FIM02: FIM10E3E16000040

Master FPM Blade: slot-4

Slot 3: FPM20E3E17900113

Status:Working    Function:Active

Link:      Base: Up          Fabric: Up

Heartbeat: Management: Good    Data: Good

Status Message:”Running”

Slot 4: FPM20E3E16800033

Status:Working    Function:Active

Link:      Base: Up          Fabric: Up

Heartbeat: Management: Good    Data: Good

Status Message:”Running”

Log into the primary FPM CLI and run the command diagnose vpn tunnel list <phase2> to show the sessions for the phase 2 configuration. The example below is for the to-fgt2 phase 2 configuration configured previously in this chapter. The command output shows the security association (SA) setup for this phase 2 and the all of the destination subnets .

Make sure the SA is installed (In blue color). And the “dst” are correct (in red color).

CH15 [FPM04] (002ipsecvpn) # diagnose vpn tunnel list name to-fgt2

list ipsec tunnel by names in vd 11

—————————————————–name=to-fgt2 ver=1 serial=2 4.2.0.1:0->4.2.0.2:0

bound_if=199 lgwy=static/1 tun=intf/0 mode=auto/1 encap=none/40 options[0028]=npu ike_assit

proxyid_num=1 child_num=0 refcnt=8581 ilast=0 olast=0 auto-discovery=0 ike_asssit_last_sent=4318202512 stat: rxp=142020528 txp=147843214 rxb=16537003048 txb=11392723577 dpd: mode=on-demand on=1 idle=20000ms retry=3 count=0 seqno=2 natt: mode=none draft=0 interval=0 remote_port=0 proxyid=to-fgt2 proto=0 sa=1 ref=8560 serial=8

src: 0:4.2.1.0/255.255.255.0:0 0:4.2.2.0/255.255.255.0:0 dst: 0:4.2.3.0/255.255.255.0:0 0:4.2.4.0/255.255.255.0:0

0:4.2.5.0/255.255.255.0:0

SA: ref=7 options=22e type=00 soft=0 mtu=9134 expire=42819/0B replaywin=2048 seqno=4a26f esn=0 replaywin_lastseq=00045e80

life: type=01 bytes=0/0 timeout=43148/43200

dec: spi=e89caf36 esp=aes key=16 26aa75c19207d423d14fd6fef2de3bcf ah=sha1 key=20 7d1a330af33fa914c45b80c1c96eafaf2d263ce7

enc: spi=b721b907 esp=aes key=16 acb75d21c74eabc58f52ba96ee95587f ah=sha1 key=20 41120083d27eb1d3c5c5e464d0a36f27b78a0f5a

dec:pkts/bytes=286338/40910978, enc:pkts/bytes=562327/62082855 npu_flag=03 npu_rgwy=4.2.0.2 npu_lgwy=4.2.0.1 npu_selid=b dec_npuid=3 enc_

npuid=1

Log into the CLI of any of the FIM modules and run the command diagnose test application fctrlproxyd 2. The output should show matching destination subnets.

Troubleshooting

diagnose test application fctrlproxyd 2 fcp route dump : last_update_time 24107

Slot:4 routecache entry: (5)

checksum:27 AE 00 EA 10 8D 22 0C D6 48 AB 2E 7E 83 9D 24

vd:3 p1:to-fgt2 p2:to-fgt2 subnet:4.2.3.0 mask:255.255.255.0 enable:1 vd:3 p1:to-fgt2 p2:to-fgt2 subnet:4.2.4.0 mask:255.255.255.0 enable:1 vd:3 p1:to-fgt2 p2:to-fgt2 subnet:4.2.5.0 mask:255.255.255.0 enable:1

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