Recent content by just2cool

  1. J

    BGP Dual home Problem

    Incorrect -- the limit is /24. Forcing anything less specific means you should tell your SP to do their job properly or dump them for one that does. Most SPs are terrible -- I usually need to repeat "escalation" 5 times before I get someone who knows what they're doing. As long as you...
  2. J

    Help on a connection to a Cisco 2970G

    A bit more of a stretch, try "switchport nonnegotiate" as well. I recall this giving me problems at some point. This "feature" is called DTP and tries to negotiate the other side to be a trunk and occasionally confuses the other side. (another annoying Cisco command btw). Also, try playing...
  3. J

    Cisco 2960S - Flow control

    No offense taken. The financial industry is full of nutcases like myself. We actually look at packet rates down to the millisecond-by-millisecond level and export buffer levels from switches (5-10 microseconds granularity from the Nexus3K and the like). We've seen a 5 Gbps 1 milisecond burst...
  4. J

    Cisco 2960S - Flow control

    Don't turn on flow control -- it probably won't fix anything. Flow control from the switch's perspective requires a pause frame to be sent from the connected host to the switch, which is essentially a white surrender flag. A host rarely does this unless something is really wrong with it or the...
  5. J

    Help on a connection to a Cisco 2970G

    en conf t int g0/25 speed nonnegotiate This is 100% likely to solve your problem, provided it is a working Cisco SFP supported by the 2970 and the fiber isn't damaged. Those speed 1000 / duplex commands don't apply for this. And flip polarity again if you have to. This is the most...
  6. J

    A small datacenter build and other projects

    We also use infiniband extensively. It is used in every serious wall street / financial firm in the world like mine, as well as a lot of HPC environments. We don't care about the cost savings. The latency difference (especially due to RDMA) is huge. RDMAoE/iWARP isn't quite there yet...
  7. J

    Network pics thread

    Haven't had the chance to look at it yet -- there's a few demo boxes on my desk. I'll be evaluating it mid-January. If you're interested, I'll shoot you a PM with what I find.
  8. J

    Network pics thread

    Interesting. We recently passed on 100G and the MX routers for the time being. Although not the same, I think bundled 40G MAN links across DWDM give you a lot better bang for your buck. Also, modern L3 ethernet switches seem to be displacing a lot of chassis routers (if you don't need MPLS...
  9. J

    Network pics thread

    Agreed 100% for L3. For L2, the Arista 7050T would be great and much cheaper. That 3560 abomination is 3+ years old -- and assuming cisco marketing math -- runs at 53% line rate with shallow per-port buffers ... disgusting and overpriced compared to other solutions today.
  10. J

    IT people -- am I paid fairly?

    I feel overpaid too, especially for being 26. Not complaining, though. When I walk around NYC and see ballers with their $100 million condos.. they make me feel poor again.
  11. J

    ISP Gave us 2 ranges. Not sure what to do.

    If you care about reliability, you should never use those. All of them are cheaply made crap ... I looked like a hero when I first went to my new job and fixed a lot of circuit issues by taking all media converters and throwing them on the curb for SPs to pick up later. Also, some SPs...
  12. J

    can you get around broadcasting between vlans?

    I'm not too sure. ip helper-address makes the DHCP request the source of the vlan gateway (makes sense right? because the DHCP client has no IP). But this is different because it's forward-protocol. Try both and see what happens. It's going to be one IP or the other. I'm going to guess it...
  13. J

    can you get around broadcasting between vlans?

    Looks right to me. Can't tell from the output there, but make sure your SVI address is the physical address, not HSRP VIP or any of that crap.
  14. J

    can you get around broadcasting between vlans?

    As damacus said, you still need the forward-protocol commands as well. The forward-protocol commands tell the router to map UDP ports to the helper address anytime a broadcast message comes in. The ip directed-broadcast command is completely separate -- the only thing it knows is that it has...
  15. J

    can you get around broadcasting between vlans?

    Yes, that's correct. I've used this once in a lab before. Just be careful with ip directed-broadcast ... that does more than you think. Aside from your helper statement with those ports, any packet destined for 10.128.12.255 sourced from anywhere in your network will be flooded on that vlan...
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