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I have the following configuration: Netgear FSV338 vpn filewall(NAT and DHCP) connected to the LAN port of NETGEAR WNDR3400 router.

When I connect to the network, I can only see the firewall's ip and not the router's ip. It is as if the router doesn't have an IP, which seems impossible. If I connect my computer directly to the router I still cannot access it. Why would the router not appear on the wireless networks it created?

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    Have you set the router's ip configuration manually (best to do so). If not, it might have a default static address that's not in the same range the DHCP server is leasing addresses. – Terry Jul 22 '15 at 15:02
  • @Terry It was that the static IP of the router on LAN equaled the IP of the firewall on LAN. If you put your comment as an answer, I'll check it. Also the wifi has had some connection issues (such as wrong password for the right password, the range is bad), could this have been causing it? I was told to also change the default netgear channels. – dylan7 Jul 22 '15 at 15:20
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    When you work in client environments, it's often enough to assign auto channel for your wifi. Use an application like inssider to monitor wifi activity near you (or pingtools on android). – Terry Jul 22 '15 at 15:27
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Routers/firewalls mostly come with their own default static IP address (also depending on manufacturer and model). If the IP address of your router is not within the same range as your DHCP server, you will not be able to access it.

For example: your firewall has address 192.168.1.1 (subnet 255.255.255.0) and distributes 192.168.1.50 to 192.168.1.200, you will have (as first device asking for an address) the IP-address 192.168.1.50. If your router still has its static address which is not in the range (like 192.168.0.1), you will not be able to access it. Also beware of default IP-addresses being the same, some vendors have the same default IP address.

Best practice when creating a new network setup is defining which networks scheme you want to use and assigning static addresses to key devices (firewall, router, server, printers,...). When you install a device, just directly connect your computer to that device and connect to their default IP address. That way, you won't have to deal with double IP addresses.

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The logic that Terry gives needs a correction, or it risks allowing the OP's problem to repeat itself.

The OP's confirmed problem (see comments on question) was that there was an IP address conflict, due to the fact that the firewall and router both had the same, default, statically-assigned IP address. The solution was to manually change the static IP of the router, resolving the conflict.

However, the logic Terry expresses to underpin his answer is misleading, when he said that, "If the IP address of your router is not within the same range as your DHCP server, you will not be able to access it." In fact, you want your static IPs to be placed outside the range which the DHCP Server uses to lease IPs, in order to prevent future conflicts when a new device is connected via DHCP. The important mechanic at work (as Terry's example correctly denotes) is that all hosts share the same network range per the subnet mask.

For example, if your subnet mask is 255.255.255.0, and the rest of your network's IPs have as their first three numbers 192.168.1.x, then you could have x=1 be the gateway (the firewall in this case), 2<=x<=50 be reserved to be statically (manually) assigned (x=2 would make a good router IP), and have the DHCP pull from the range 51<=x<=100. All 192.168.1.x hosts can communicate with each other being on the same network/subnet, regardless of static/dynamic origination. But the DHCP will never step on the toes of your static addresses.

(Reference [see section How IP Address Conflicts Happen, second bullet]: https://www.lifewire.com/what-is-ip-address-conflict-818381 )

  • (1) Quote or paraphrase; choose one.  Do not use quotation marks and then use words different from what the other person actually said.  If it’s easier to make your point by rephrasing (paraphrasing) the original statement (e.g., «Mary said that she likes cats.»), then do so, but don’t use quotation marks. … (Cont’d) – Scott Jan 7 at 8:30
  • (Cont’d) … (2) Terry’s answer is not “completely wrong”; it is ambiguous / misleading, and you misinterpreted it. Terry didn’t say anything about the IP address of the router relative to the DHCP server’s DHCP address distribution range, per se; the statement was that, if the router has a default static IP address that is not in the operational network range of the other network devices, then they will not be able to communicate. Terry’s answer gives the example of a router with an address of 192.168.0.(something)/24 on a network where everything else is 192.168.1.(something)/24. – Scott Jan 7 at 8:30
  • Respectfully, I stand by both (1) and (2): – Beerman58 Jan 9 at 13:44
  • (1) I did use quotation marks on purpose to correctly repeat the exact sentence in Terry's post that best summarized Terry's repeating misleading logic. (Try an on-page browser find of you don't believe me.) ...(Cont'd) – Beerman58 Jan 9 at 13:53
  • (Cont'd)... (2) You said: "Terry didn’t say anything about the IP address of the router relative to the DHCP server’s DHCP address distribution range, per se...” umm... Yes, he does. Repeatedly. (Including once in Terry's first comment to the original question then multiple times as the underlying logic pinning down the answer; again, try a browser search on "DHCP" and "distributes"). Bottom line, I'm in the same boat as the OP and wasted my time before my post trying to re-understand what is DHCP after being mislead by Terry's answer (see reference link). ...(Cont'd) – Beerman58 Jan 9 at 14:13

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