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  • #2188963

    Multiple GW on 1 flat network


    by swetzel ·

    Is it possable to have multiple GW routers on one flat network and just have certain systems point to certain GW routers?

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    • #3060859

      Reply To: Multiple GW on 1 flat network

      by hozcanhan ·

      In reply to Multiple GW on 1 flat network

      certainly, it is possible ! do you have a very big network or money ? How do you think ISPs have so many uplinks ? Please comment why you want this ?

    • #3045476

      Reply To: Multiple GW on 1 flat network

      by dplewis ·

      In reply to Multiple GW on 1 flat network

      Short answer – yes.
      There are a few scenarios I can foresee:
      1) You want multiple gateways in the same subnet maybe for resilience – in which case you would be best implementing VRRP or similar to provide a virtual Default Gateway.
      2) You want to loadshare between these gateways. Simple way – set up a DHCP scope for each gateway with half the IP addresses required in each. More deterministic way – If you’ve got newer Cisco high-end switching gear you can do resilient and load-sharing Default Gateway with the GLBP feature.
      3) If you want muliple gateways on different subnets (why?) – known as multi-netting – you need to make sure it’s supported on your L3 switches. Basically on most gear you add a secondary IP address. Note that if using DHCP in this setup you can only lease IP addresses from one of the subnets.
      4) If you want to have different hosts send their default route traffic via a different path, just configure them with the different default gateways (i.e see 2). Make sure the gateways can’t exchange routing information, though (switch off RIP, OSPF etc.)
      Hope this helps,

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