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Unstable primary router - rock solid secondary router: please help

Discussion in 'General Wireless Discussion' started by elsaddiq, Sep 13, 2016.

  1. elsaddiq

    elsaddiq New Around Here

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    Greetings:

    I recently setup a home network using two routers: one for a private network (with file sharing, print sharing, etc.) and the other for a guest network with no shares or access to the private network. The routers are tied together on different floors of a two story home using MoCA.

    For reasons unknown, the primary (private) router occasionally drops the internet connection while the secondary router remains rock solid. I'm not even sure how that's possible. They both have static ips with the secondary router's ip being outside of the range of the primary router. The primary router handles DHCP with the secondary being setup as an access point. I have noticed on one of my devices connected to the primary router, authentication errors, but multiple wireless devices on this router lose connectivity. Devices on the secondary router never lose connectivity.

    Anyone have any ideas? Thanks.
     
  2. abailey

    abailey Very Senior Member

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    It may help to give a little more information about your setup. What are the models of the routers? Are the routers in the same subnet? How are the two connected (I don't mean by MOCA, I mean are you connecting them using a LAN port of the Primary to the WAN port of the secondary)?
     
    elsaddiq likes this.
  3. ktriebol

    ktriebol Occasional Visitor

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    Does the problem still occur if you shut down the secondary router and totally remove it from the system?
     
    elsaddiq likes this.
  4. sfx2000

    sfx2000 Part of the Furniture

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    The "secondary router" can be a problem if not set up correctly - for example, IP range overlap or a secondary DHCP server can cause a lot of problems...
     
    elsaddiq likes this.
  5. elsaddiq

    elsaddiq New Around Here

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    Sorry guys, the title should have been "Unstable Primary Router." The secondary router is rock solid. This is what I can't understand.

    The primary is a Cisco DPC3941T Modem/Router/Gateway setup with static ip in the 10.x.x.x range. This has to be the primary do to the need for landline phone service. The secondary router is a Linksys WRT54G that also runs DHCP but in the 192.x.x.x range and with a static ip in the range of router 1 (but outside of the range of router 1's DHCP assignment range). The secondary (on the second floor) connects to the primary by way of a MoCA adapter to one of the LAN ports on the secondary. The primary is a MoCA compatible device.

    This setup was given to me by an acquaintance that's a network administrator for a major company but I've been unable to get a reliable setup going. I have two problems: The primary loses connectivity randomly AND I'm unable to access the web interface of the secondary to troubleshoot once everything is up and running as if the secondary's ip is not remaining static.

    Thanks.
     
  6. elsaddiq

    elsaddiq New Around Here

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    The primary is fine without the secondary so I know the conflict is with the secondary. I'm just not sure where.

    DNS servers match, subnet is the same, gateway points to primary, lan ports are static outside of primary's DHCP range, etc.
     
    Last edited: Sep 15, 2016
  7. netwrks

    netwrks Senior Member

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    Let the Cisco be the Base router for your network / DHCP Server, and set the Linksys and whatever other routers you as an Access Point(s).
     
    elsaddiq likes this.
  8. elsaddiq

    elsaddiq New Around Here

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    I'm running DHCP on both to avoid co-mingling of the networks. One is in the 10.x.x.x range and the other in the 192.x.x.x range.
     
  9. Samir

    Samir Very Senior Member

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    Even though you're running two different subnets, the networks are still co-mingled, but not bi-directionally. The Linksys traffic can see all the Cisco lan devices, but not vice versa. If this is what you want, then fine. But if you don't need this, there are ways to simplify the network.

    As far as the conflict, this is a toughy. A couple of things to try. Bring the Linksys down and connect it to the Cisco directly with a cable. If that works, then while still downstairs, connect it via moca. If that still works, check the speed/duplex setting on the linksys and moca adapters. Set them manually and see if that helps. Post back with results and we'll go from there...
     
    elsaddiq likes this.
  10. elsaddiq

    elsaddiq New Around Here

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    The Linksys works fine connected directly to the Cisco and again when reconnected to MoCA.

    I would like the reverse of what you mentioned above. It's okay for the Cisco traffic to see the Linksys devices but not for the Linksys traffic to see the Cisco devices. Remembering that the Cisco is a voice/modem/router gateway, is there a way to simplify this network while getting stability and achieving the above goals? I'm open.

    Thanks again for all of the responses.
     
  11. Samir

    Samir Very Senior Member

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    So this sounds like the Moca may be having issues then as that's the only thing that changes that causes the problem to start. See if you can connect a computer to the moca where the Linksys normally connects, and then have that computer send continuous pings to the cisco's IP address, ie 'ping -t 10.10.10.1'. Let it run like this for at least a day. Then stop it and look at the stats--you should have packet loss <1%. Anything higher and I think we've found the problem.

    As far as the network separation issue, unfortunately the only easy way would be to swap all the device from one router to the other and vice versa. A router behind another router will always be able to see the first router's network since the first network treats the second router like any other lan device.

    Now, there's a couple of tricks that may work, but they depend on how the cisco gateway can be set up. One way would be to use vlans if it has that capability. You could put the cisco lan in one vlan and then the ip that your linksys connects in another vlan. But this will be complete separation which may not be what you want.

    Another way would be to get a second public IP address from your ISP. The linksys would get this public IP address even though it would be connected to the cisco. Again, the two networks would then be completely separate.

    Some routers' dmz does not allow the lan to connect to the dmz. If the cisco works like this, then you could put the linksys in the dmz, and completely separate the networks.

    As far as getting the cisco lan to see the linksys, but not vice versa, I think the only easy one there is to swap all the devices. That might not be too bad either as you could just get a switch at each location and then just have one cat5 run back to each router from the switch. Since you'd need two runs and the moca link is only one of those runs, this solution gets even more messy since there would have to be a way to be another run either on the same wire or via some other means.

    That's all I got for now. Hope some of this helps.
     
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  12. elsaddiq

    elsaddiq New Around Here

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    Alright, trying to go a different way with this.

    If I turn DHCP off on router two, can I still set the static ip for that router to the 10.x.x.x range? If so, will the DHCP from router one then give devices connected to router two ip addresses in the 10.x.x.x range or will it still use the 192.x.x.x range? Or, will it be random?

    Also, should I point router two's gateway ip to router one's internal ip address or to the external gateway ip address of router one?

    Finally, if I set router two to a static ip, should I set router one's LAN port to the same static ip since this is where router two connects, or should it have its own static ip?

    Thanks again.