You also need to ensure that the router is allowing IP protocols 50 and 51 for ESP and AH respectively in and out of the Sonicwall assuming you will be creating an IPSec tunnel..
Thanks,
Kent
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Browse All TopicsI have a SonicWall sitting behind a Cisco router. I am trying to configure the Sonicwall to have a routable IP so that it can communicate with another SonicWall offsite. Could someone please show me the best possible setup? Any help is appreciated.
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The router is my router. The ISP only setup their end... I indeed do have available addresses to use, as I am already using a handful for other purposes. Would the SonicWALL be assigned on of these public IP's as the WAN interface, along with the corresponding subnet, DNS, and gateway addresses? Or will I be putting in some NAT statements to resolve the public back to the sonicwall on a private address?
Thanks,
If you have public IP addresses to spare, then set the Sonicwall WAN up on one of them, so no NAT is happening on the router (do NAT on the Sonicwall to your protected network). Then it's pretty straightforward. Each end of the link you set up the VPN ...
(If using Enhanced OS, first create a "network" range name on each firewall thus:
On siteA sonic, create a range called SiteBLanRange set it to the lan range of Site B
On SiteB sonic, create a range caleld SiteALanRange, set it to lan range of Site A - Tricky stuff huh! :-)
If you don't have Enchanced OS, you will have to manually insert the laN IP ranges in the VPN config when you reach that point.
Main VPN page. Tick the ENable VPN box if it isn't on already. The default Firewall Identifier will be your Firewall's serial number - that's good enough, and you should certainly not change it if you are already using any VPN tunnels.
VPN Policies - Site A
Create a new Policy.
Auth - IKE using PreShared Secret.
Name = SiteB
IPsec Primary Gateway - ste this to the IP address of the WAN side of the SiteB sonicwall
IPsec Secondary = IF the SiteB firewall has a dual WAN connection, set this to the IP of the second.
Shared Secret = make up a password/phrase. Type it in twice. Remember it, youl'l need it on SiteB setup.
Local IKE ID - Type = IP Address - Leave Blank
Peer IKD ID - Type = IP address - Leave Blank
Networks
Choose local network from list - select "Firewalled Subnets" (a default range).
Choose dest network from list - select "SiteBLanRange" (created above).
Proposals - Phase 1
Ech = Aggressive mode
DH Grp = Group 2
Encrpt = DES
Auth = MD5
TTL = 28800
Proposals - Phase 2
ESP
DES
MD5
(do not enable PFS)
TTL 28800
Advanced
Enable KeepAlive
Save it
Remember to check the ENABLED box for the policy
Repeat the process at Site B but remember to use SiteALanRange, and the Site a WAN ip address(es).
Once you have both sides configured and enabled they should just hook up automatically - a green blob will show agsinst the porlicy once it's active and logged on.
ONCE YOU HAVE IT WORKING then (not before) feel free to tinker with the settings, e.g. try 3DES instead of DES. But get it working first! :-)
Oh - you *do* have DIFFERENT ip ranges on each LAN don't you? You *can* set it up where both LANs have the same range but you have to do a complex double-loopback-reNat thing that makes my head spin. Avoid, don't, set the LAN ranges to be different.
If you HAVE to do this behind a NAT router, it should work but make sure the router isn't interfering with ANY of the packets. In particular, if the router is offering to be a VPN host, turn that OFF so the router doesn't suck in the incoming IKE packets. Really, if you can, do NAT on the Sonicwall NOT on the router.
If behind NAT, do NOT change the phase 2 proposal from ESP to AH - AH type proposals include the source Ip address in the encoding so of course NAT screws it up.
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by: tl121000Posted on 2009-04-08 at 13:40:33ID: 24101493
First - is the Cisco Router your router or the ISP's router (known as Customer Premise Equipment - CPE)?
If CPE, you need to see if you have an available public outside global address.