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Router bloicks WAN IP for Cisco VLAN

bgraves
bgraves asked
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Last Modified: 2018-09-22
Cisco RV345 router in a static IP mode.
ISP gives me IPs of   x.y.z.232 /29 with gateway x.y.z.233
I set RV345 WAN as x.y.z.234 /29

Now I try to define a globally known address using a VLAN to connect a server:
  so maybe a server at x.y.z.236 with an interface on a port asdsigned to VLAN1.
  VLAN 1: IP x.y.z.235 /29  and the RV345 gives a red box and won't allow it.
  because I am not so smart, I try /30 and it also errors
  Tried other IPs, x.y.z.236 through x.y.z.238 and they all fail
  Any IP OUTSIDE the router's WAN range x.y.z.232 /29 is allowed.

I want the server's IP to be one of the ISP assigned values, but the RV345 seems to prevent it.
What am I missing here?
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Sr.Net.Eng
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JohnBusiness Consultant (Owner)
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Expert of the Year 2018

Commented:
I want the server's IP to be one of the ISP assigned values, but the RV345 seems to prevent it.

That is normal (I have a Cisco RV325).  The outside WAN is for your external IP and the inside WAN is a non-routable IP range like 192.168.x.x

Author

Commented:
So, Soulja,
Would I use a static NAT to map WAN x.y.z.236 /29 to x.y.z.236 /29 or would it have to be internal IP like 192.168.x.x?
The 192.168.x.x is a problem since the targeted device is a Sonicwall, it needs to know what incoming WAN IP was used to address it.
SouljaSr.Net.Eng
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Commented:
You would nat one of your public ip's to an internal one for that server you are trying to set up.

Author

Commented:
Multiple WAN IPs go to same server. The server inspects the WAN IP address to determine where/what to do.
So, let me check my understanding here, I would NAT each global WAN to a separate 192.168.x.x type IP and then setup the target server with something like 192.168.x.y /29 so it can handle them all?
SouljaSr.Net.Eng
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Commented:
What do you mean the server inspects the wan ip? What type of server is this? I am referring to one to one nat's. One public ip to one internal Ip.

Author

Commented:
The router feeds a Sonicwall firewall. The Sonicwall does the mapping of multiple WAN addresses to internal servers.
I do understand the the RV345 could do this but we are trying to mirror an old vendor supplied system with a Cisco 1841 feeding the Sonicwall and the old system did this forwarding just fine.
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Commented:
Static NAT is the only way you could do it with that device, which is what Soulja already told you. Sonicwalls are far more flexible in this sense, that you can have any public IP in your block translate to any local address behind it that you like.

Can the Sonicwall have multiple public IP addresses translate to the same private IP? Yes. How would a session behave when doing that, would actually be a good question. Never had a reason to do it.
Can the RV345? Highly doubtful. Given the way it's design is for static NAT, you probably won't be able to do it.

The router feeds a Sonicwall firewall. The Sonicwall does the mapping of multiple WAN addresses to internal servers.
I do understand the the RV345 could do this but we are trying to mirror an old vendor supplied system with a Cisco 1841 feeding the Sonicwall and the old system did this forwarding just fine.
Are you trying to have the RV345 feed a Sonicwall? If the answer to that is yes, then that's a waste of hardware. You could just have the Sonicwall and be done with it.