Second outbound NAT for specific IP address

Question

Hi Forum, I have a unusual (I think) query. 
 We are splitting with another organisation and migrating away from their Cisco 6500 to a SG330 UTM. We have our own public IP address range that is routed to the UTM and have setup our own private IP ranges. The private IP ranges access the internet with a standard NAT masquerade & a SNAT. 
 However we still need to access a fileserver that is on the old Cisco 6500. The UTM can access the VLAN that the file server is on, although obviously the subnet is "owned" by the 6500. We can put a UTM interface on the file server's VLAN, but I can't figure out how to route traffic to it. 
 My plan was to use a NAT to the UTM interface on the storage VLAN to access the file server, but since the private subnets already have a Masquerade rule, I don't see how this will work. Could I set a static route for this subnet to point to a bridging network which then nats out onto the storage VLAN? 
 Cheers Jon

JonRhoades · Accepted Answer

I don't know what I was thinking. In case anybody ends up in this situation what I did was.... 
 
 Added the VLAN as an interface on the UTM, but created a different gateway from the one that was on the Cisco 6500. Then on the fileserver added a default route for our new network to the UTM's gateway.