Announcement

Collapse
No announcement yet.

WAN/LAN Throughput Issue

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • WAN/LAN Throughput Issue

    Hell,

    I have a 3660 Router, IOS 12.3(22), WAN Interface NM-1GE, 3 LAN FE ports.

    If I have 3 physical FastEthernet LAN ports (each setup on different VLAN's), and a Gigabit WAN port, should I have an issue with getting more than 100Mb throughput on the WAN interface?

    Specifically, if each of the 3 physical FE ports is passing 40Mb of traffic, and the combined total of those 3 is 120Mb, shouldn't this design support greater than 100Mb of throughput?

    As it stands, I see this limited to roughly 100Mb (less than that, due to overhead etc), but ultimately I can't pass more than 100Mb of traffic and I don't see why I would be limited by the FE interfaces if they each support up to 100Mb etc.

    Any input would be appreciated. If any other information is needed please let me know.

  • #2
    Re: WAN/LAN Throughput Issue

    What is the maximum throughput on the 3660? Just cause you have a 1gig interface or a 100Mbs interface does not mean you will get line rate all the time. Typically if your router has a max throughput of 100Mbps then that would be 50Mbps up and 50 down (aggregate bandwidth). Also what speed circuit is on the Wan side? I doubt its even 100Mbps (i could be wrong though).
    Last edited by auglan; 17th December 2012, 18:37.
    CCNA, CCNA-Security, CCNP
    CCIE Security (In Progress)

    Comment


    • #3
      Re: WAN/LAN Throughput Issue

      Originally posted by auglan View Post
      What is the maximum throughput on the 3660? Just cause you have a 1gig interface or a 100Mbs interface does not mean you will get line rate all the time. Typically if your router has a max throughput of 100Mbps then that would be 50Mbps up and 50 down (aggregate bandwidth).
      Based on what I have found, it looks like it should be 320Mb, so at that, 160Mb tx/rx? Of course, the other factors of cpu usage etc are factors on everything. As it stands, during the period the bandwidth is stuck at 100Mb, cpu usage is at 60%. There is a minor amount of NAT occurring, and no access lists aside from 1 specifying a small network to be NAT'd.

      Thank you for your input. It is appreciated.

      Comment


      • #4
        Re: WAN/LAN Throughput Issue

        Your cpu seems very high for normal operation as well. Is that 60 percent at peak or normal usage. You are also running old code (12.3 etc) Have you opened a TAC case to see if those numbers are accurate for that platform or a possible bug issue?
        CCNA, CCNA-Security, CCNP
        CCIE Security (In Progress)

        Comment


        • #5
          Re: WAN/LAN Throughput Issue

          Originally posted by auglan View Post
          Your cpu seems very high for normal operation as well. Is that 60 percent at peak or normal usage. You are also running old code (12.3 etc) Have you opened a TAC case to see if those numbers are accurate for that platform or a possible bug issue?
          The CPU is during peak traffic, and runs around 20% outside of peak until I start reaching 60-70Mb of traffic at which it hits 30-40%, and then rises to roughly 60% when traffic hits the 95-100Mb mark.

          My CPU goes up with traffic. CPU usage during peak is all IP traffic. So the CPU is high because of the traffic.

          Comment


          • #6
            Re: WAN/LAN Throughput Issue

            My CPU goes up with traffic. CPU usage during peak is all IP traffic. So the CPU is high because of the traffic.
            Okay this is to be expected. Are you noticing excessive packet drops and/or excessive queuing on those interfaces?
            CCNA, CCNA-Security, CCNP
            CCIE Security (In Progress)

            Comment

            Working...
            X