r8000p why would lan connections break when wan fails?

Question

On my r8000p i have wired connections to my windoze server that runs dns, dhcp, web services, file shares, etc.&nbsp; On WiFi i have both windoze and i-thingy clients.&nbsp; When my WAN connection goes down the machines on the LAN suddenly can't connect to each other, and actually lose active connections(even ones with machines that have static addresses) so i can't really blame a server dns or dhcp problem.&nbsp; Why would dropping a WAN connection cause the LAN to misbehave like that???

michaelkenward · Answer

k1ttt&nbsp;wrote:
Why would dropping a WAN connection cause the LAN to misbehave like that???

It shouldn't. So some more details might be useful.
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What firmware version do you have on the device? A number is more useful than "the latest". (It may not be by the time people read this.) There can also be newer versions, or "hot fixes", that do not show up if you check for new firmware in the browser interface.It might also help if you told people what the modem is in front of this router, if there is one. The make and model number could be useful. Is it, by any chance, also a router, with a set of LAN ports on the back?The reason for asking is that a lot of people turn up here trying to put a router behind a modem that is also a router. That can complicate troubleshooting.

k1ttt · Answer

Firmware Version&nbsp;&nbsp;V1.4.4.94_1.3.56&nbsp;the wan configuration is like this... which took spectrum a week to figure out and configure properly as we are their first home fiber installation town, and i am their first small business' account on that system... I have a static IP which is assigned to the r8000p, with ip = x.x.x.190, netmask=255.255.255.252, gateway x.x.x.189.&nbsp; the internet port of the r8000p goes to a spectrum router gateway with the x.x.x.189&nbsp;ip which then goes to their fiber modem which is a brand new gb capable box that they upgraded me to when the old one had some kind of intermittent problem.&nbsp; only 1 port on the spectrum router is used, the one to my r8000p, the wifi ports are disabled as are all it's services like dhcp, etc, as far as i can tell their router is just passing through everything going and coming to my router, i tried to get more detail from spectrum about it but apparently only one person somewhere in their engineering group could even figure out how to provision it.&nbsp; &nbsp;i could get numbers off them but don't know if they are spectrum part numbers or something else so they may not be that useful.&nbsp; on the r8000p the dhcp, dns, guest lan, and lots of other stuff is disabled, i do dhcp and dns from my server on the lan, the r8000p does do nat for several incoming services used for ham radio stuff.&nbsp;the real confusing part for me is that the server has static ip's for its network ports, 192.168.0.2 and .3, as do many of the single purpose windoze machines on wifi or ethernet ports and they all lose connections... or well maybe the wired ones might stay connected to the server, there are 2 special purpose machines on the lan that are wired ethernet to the router along with the server, they might still work but the only thing they connect to are outside addresses so they die anyway if the wan goes down... but all the wifi connected stuff is left stranded and can't even connect to the server, and they even lose active existing connections to the server which is really annoying!&nbsp;&nbsp;

michaelkenward · Answer

Heaven only knows what that network configuration is all about. I don't. It seems to be a recipe for chaos.
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What is the reason for those "static" IPs. That term gets widely abused and&nbsp; misunderstood.
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Do you mean that the ISP has given you a fixed (WAN) IP address on the Internet. Or are you talking about IP addresses on your local network.
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More important, the other question I asked, what is the modem/router in between the R8000P and the internet?
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as far as i can tell their router is just passing through everything going and coming to my router, i tried to get more detail from spectrum about it but apparently only one person somewhere in their engineering group could even figure out how to provision it.&nbsp; &nbsp;
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Perhaps they didn't understand your question. But I am suspicious about the "as far as i can tell " bit.
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Look at whatever label is on their router. If it really is a router, then you hit the first wall that catches many people out.
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Two routers on your network can cause headaches. For example, you can end up with local address problems. Among other things, the other router can misdirect addresses that the Netgear router usually handles, such as routerlogin.net or the usual IP address for a router, 192.168.1.1.This explains some of the other drawbacks.What is Double NAT? | Answer | NETGEAR SupportUnless you have specific reasons for using two routers – to create two separate networks for example – it is often easier to use just one router and then to set up the second router as a wifi access point. Netgear advises this, as does just about every site you will visit.It may be possible to put the modem/router into modem only (bridge) mode and then to use the second device as the router. But some Internet service providers, such as BT in the UK, supply modem/routers that won't work in bridge mode. There may be ways to get the modem/router to cooperate. Sometimes it is easier to put the second router into AP mode. But that has its own drawbacks:Disabled Features on the Router when set to AP Mode | Answer | NETGEAR Support

k1ttt · Answer

my ISP (Spectrum) assigns me the (static) x.x.x.190 as my wan side ip address which i put in manually to the r8000p instead of letting the wan side do dhcp.&nbsp; they also assign the x.x.x.189 manually to their router that is my gateway to their network, i have no idea why they need that router but thats how they made the whole thing work.&nbsp;I assign 192.168.0.* addresses manually in the windows network configuration for certain machines that use or need to be accessed on the lan by software that doesn't like to resolve names properly from my windows server dns.&nbsp; those are also 'static' because they can't be changed by dhcp.&nbsp;their router is a 'Spectrum' branded 'sagemcom fast-5280' if i am reading that fine print upside down on the back of the router.&nbsp; I have dealt with other company branded routers in the past and that fast-5280 may or may not work the same as a sagemcom one you could buy... if they actually sell them retail.&nbsp; NOTE: Their router is not seen by my lan, it is in series between the spectrun ont and the internet port on the r8000p.&nbsp;There is no 'double nat', my r8000p holds the public static ip x.x.x.190.&nbsp; For some reason they had to put a gateway router that just forwards my outgoing x.x.x.190:port address out to their backbone as-is.&nbsp; it also forwards incoming x.x.x.190 addressed packets to my r8000p as-is and the r8000p acts as a firewall for everything except the incoming ports i have it programmed to nat and forward to my lan machines.&nbsp; all of that works fine and perfectly as expected except for when the r8000p loses the internet connection and breaks the internal lan routing.&nbsp;the 'as far as i can tell' is because i have not tried to put a packet analyzer on the input and output of their router.&nbsp; but i do know that external internet services see my 'static' x.x.x.190 address and port as expected, and incoming data to x.x.x.190 is recognized and sent to the proper lan machine and port.&nbsp; i have figured out that it gets even more confusing on their side because the wan side of their router that provides my router with the x.x.x.189 gateway gets a dhcp address from their network services, but i have only seen that because i was helping them debug a faulty gateway router that served our new town network and was failing to wrap requests from my neighbors back to my x.x.x.190 public address so it broke them getting to my local weather web pages.... the problem was a brand new router that should have had a firmware update before it was installed.&nbsp;&nbsp;&nbsp;

michaelkenward · Answer

k1ttt&nbsp;wrote:
my ISP (Spectrum) assigns me the (static) x.x.x.190 as my wan side ip address which i put in manually to the r8000p instead of letting the wan side do dhcp.&nbsp;
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OK. That sorts out that one. A rare arrangement for iSPs, but one that Netgear's routers are designed to accept. In theory at least.
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The rest of the setup is also atypical. Two routers that, you say, don't have double NAT.
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So best leave you in the hands of some network experts who can make head or tail of this rat's nest of devices.
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Good luck.
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r8000p why would lan connections break when wan fails?

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