老森常譚 IT Help

　　三年前曾試過為Sonicwall NSA 2400與FortiGate 110C建立Site to Site VPN，不過失敗了，後來測試Juniper 5GT與Sonicwall倒是成功。最近又有需求要與一台FortiGate 110C建VPN，雖然手上已經有另一台FortiGate 110C，照理說直接用同型號來建會省事很多，但我還是想再試一次用Sonicwall來建，看看能不能找出當初失敗的原因，來回測試一整天，總算搞定。

雙方環境如下：

【Sonicwall設定】
1.建Object
「Network」->「Address Objects」
Name: FortiGate_network
Zone Assignment: VPN
Type: Network
Network: 192.168.100.0
Netmask: 255.255.255.0
OK

2.設定VPN Tunnel
「VPN」
Enable VPN
Add
–General tab
IPSec Keying Mode: IKE using Preshared Secret.
Name: FortiGate_network
IPSec primary Gateway Name or Address: 203.4.5.6
Shared Secret: 設一組密碼
Local IKE ID: IP Address (保留空白)
Peer IKE ID: IP Address (保留空白)

–Network tab
Local Network：LAN Primary Subnet(192.168.1.0/24、192.168.2.0/24)
Destination Networks：FortiGate_network.

–Proposals tab
IKE (Phase1) Proposal
Exchange: Main Mode
DH Group: Group 2
Encryption: 3DES
Authentication: SHA1
Life Time: 28800

IKE (Phase2) Proposal
Protocol: ESP
Encryption: 3DES
Authentication: SHA1
不勾選「Enable perfect forward secrecy」
Life Time: 28800

–Advanced tab
Enable Keep Alive.
OK

接著設定FortiGate，有Tunnel及Interface兩種方式，二擇一設定即可。(官方教學是Tunnel模式)

【FortiGate設定—1.Tunnel模式】
1.設定VPN
「VPN」->「IPSec」->「Auto Key(IKE)」->「Phase 1」
「Create Phase 1」
Gateway Name: SonicWall
Remote Gateway: Static IP
IP Address: 203.1.2.3
Mode: Main
Authentication Method: Preshared Key
Pre-shared Key: 同上面Sonicwall設定的密碼

–Advanced
Encryption: 3DES
Authentication: SHA1
DH Group: 2
Keylife: 28800
保留其他設定的預設值。
OK

「VPN」->「IPSec」->「Auto Key(IKE)」->「Phase 2」
「Create Phase 2」
Tunnel Name: SonicWall-192.168.1.0
Remote Gateway: 選SonicWall
–Advanced
Encryption: 3DES
Authentication: SHA1
不勾選「Enable perfect forward secrecy(PFS)」
(如果勾選，就算Sonicwall也勾選，仍可能造成VPN無法建立，原因不明，Interface模式則沒有此問題)
Keylife: 28800
–Quick Mode Selector..
Source address：192.168.100.0/24
Destination address：192.168.1.0/24
OK
**這邊Quick Mode一定要設才能與SonicWall建立連線。不然FortiGate會出現”no matching gateway for new request”的錯誤。

設定第二個網段(192.168.2.0)
「Create Phase 2」
Tunnel Name: SonicWall-192.168.2.0
Remote Gateway: 選SonicWall
–Advanced
Encryption: 3DES
Authentication: SHA1
不勾選「Enable perfect forward secrecy(PFS)」
Keylife: 28800
–Quick Mode Selector..
Source address：192.168.100.0/24
Destination address：192.168.2.0/24
OK

2.建立Address
「Firewall」->「Address」->「Address」
Create New
name:FortiGate_network
IP address:192.168.100.0
subnet:255.255.255.0
OK

Create New
name:SonicWall_network_1
IP address:192.168.1.0
subnet::255.255.255.0
OK

Create New
name:SonicWall_network_2
IP address:192.168.2.0
subnet::255.255.255.0
OK

把Sonicwall兩個網段設為一個群組
「Firewall」->「Address」->「Group」
Create New
Group Name:SonicWall_network
Members:SonicWall_network_1、SonicWall_network_2
OK

3.設定防火牆規則
「Firewall」->「Policy」->「Policy」
Create New
Source Interface: Port 1(or Internal)
Source Address: FortiGate_network
Destination Interface: WAN1 (or External)
Destination Address: SonicWall_network
Schedule: always
Service: ANY
Action: IPSEC (or Encrypt)
VPN Tunnel: SonicWall
勾 Allow inbound
勾 Allow outbound
OK

【FortiGate設定—2.Interface模式】
1.設定VPN
「VPN」->「IPSec」->「Auto Key(IKE)」->「Phase 1」
「Create Phase 1」
Gateway Name: SonicWall
Remote Gateway: Static IP
IP Address: 203.1.2.3
Mode: Main
Authentication Method: Preshared Key
Pre-shared Key: 同上面Sonicwall設定的密碼

–Advanced
勾「Enable IPsec Interface Mode」
Encryption: 3DES
Authentication: SHA1
DH Group: 2
Keylife: 28800
保留其他設定的預設值。
OK

「VPN」->「IPSec」->「Auto Key(IKE)」->「Phase 2」
「Create Phase 2」
Tunnel Name: SonicWall-192.168.1.0
Remote Gateway: SonicWall

–Advanced
Encryption: 3DES
Authentication: SHA1
不勾選Enable perfect forward secrecy(PFS)
Keylife: 28800

–Quick Mode Selector..
Source address：192.168.100.0/24
Destination address：192.168.1.0/24
OK
**這邊Quick Mode一定要設才能與SonicWall建立連線。不然FortiGate會出現”no matching gateway for new request”的錯誤。

設定第二個網段(192.168.2.0)
「Create Phase 2」
Tunnel Name: SonicWall-192.168.2.0
Remote Gateway: SonicWall

–Advanced
Encryption: 3DES
Authentication: SHA1
不勾選Enable perfect forward secrecy(PFS)
Keylife: 28800
–Quick Mode Selector..
Source address：192.168.100.0/24
Destination address：192.168.2.0/24
OK

2.建立路由
「Router」->「Static」->「Static Route」
Create New
Destination IP/Mask: 192.168.1.0/24
Device: SonicWall
OK

Create New
Destination IP/Mask: 192.168.2.0/24
Device: SonicWall
OK

3.設定防火牆規則
「Firewall」->「Policy」->「Policy」
Create New
Source Interface: Port 1(or Internal)
Source Address: FortiGate_network
Destination Interface: SonicWall
Destination Address: SonicWall_network
Schedule: always
Service: ANY
Action: Accept
OK

Create New
Source Interface: SonicWall
Source Address: SonicWall_network
Destination Interface: Port 1(or Internal)
Destination Address: FortiGate_network
Schedule: always
Service: ANY
Action: Accept
OK

【參考連結】

• Fortigate對SonicWALL IPSEC 實作 | Fred’s Blog
• FortiGate to SonicWall VPN setup
• IPSEC VPN for remote users – no matching gateway for new request | Fortinet Technical Discussion Forums