SureBackup Virtual Lab: Masquerade IP error?

[davegold]

Hi,

I'm doing something wrong in setting up my Virtual Lab vNIC connection IPs, hopefully someone here will see what I'm doing wrong.

Virtual Lab setup-->Network settings. Single network I'm putting in the virtual lab.
Proxy IP Number for isolated network is my original gateway: 192.168.1.1/255.255.240.0
Masquerade network is 192.168.254

When I try to save, I get the error "Specified mask parameter is invalid (MasqueradeNetworkAddress & Mask) != MasqueradeNetworkAddress."

Any ideas?

Dave

[davegold]

I think I've answered my own question, but I'm still a bit confused. Here is what I did, and why I'm confused:

Workaround/solution: Set masquerade to 10.10.0.0 range, after confirming that is not an IP range in use

Question: Shouldn't 192.168.1.1/255.255.240.0 only include 192.168.0.1 through 192.168.15.254, meaning that I should have been able to use 192.168.200.0 for the masquerade? Am I missing something here?

Thanks for any comments.

Dave

[Vitaliy S.]

Hi Dave,

The masquerade address 192.168.200.0 doesn't correlate with the mask specified, in this case you should be using something like this - 192.168.16.0, 192.168.32.0, 192.168.48.0 etc.

Thanks.

[Alexey D.]

"Specified mask parameter is invalid (MasqueradeNetworkAddress & Mask) != MasqueradeNetworkAddress."

Let me explain this message - let's do some math with your input:
MasqueradeNetworkAddress = 192.168.200.0
Mask = 255.255.240.0

1. Performing AND operation:
192.168.200.0 & 255.255.240.0 = 192.168.192.0

2. Comparing with the expression on the right side:
192.168.192.0 != 192.168.200.0

Indeed, two numbers are not equal. That happened because one bit from your 192.168.200.0 IP fell apart
(due to 255.255.240.0 netmask didn't span to that bit).

[davegold]

Ah, got it. I can choose any ofthe starting IP's that match the subnet, but not an IP in the middle of the range.

So 192.168.0 through 192.168.15 are my production range; I could use 192.168.16, 192.168.32, etc. for my masquerade.

Thanks Vitaliy and Alexey!

Dave

[Alexey D.]

You're welcome!

Yes, with the given netmask, bits 192.168.0.x - 192.168.15.x (and corresponding combinations) belong to end-client part of IP, so just make sure they don't show up in masquerade address.