Brocade Fibre Channel Networking Community

Expand all | Collapse all

Fabric OS v.6.4.3b: long distance: why should I turn off DLS?

  • 1.  Fabric OS v.6.4.3b: long distance: why should I turn off DLS?

    Posted 09-08-2014 04:40 AM

    Dear all,

     

    at the moment we're founding a new department of our company in a different location that is 5 to 10 km away from the main location. We connected the new fc switches (Fabric OS v7.1.0c) with our old fabric (v6.4.3b) over DWDM. The new fc switches joined the common fabric and everything is working smoothly, except we are having a decreased performance issue, probably due to the latency. That's why I wanted to increase the buffers by setting the long distance parameter for the particular port.

     

    On the new switch no alert is shown (DLS is activated). But on the old switches the software advices me to deactivate DLS. What is the reason for this? Should I activate the long distance parameter anyway, leaving DLS activated?

     

    Thanks in advance for your help,

     

    Michael


    #BrocadeFibreChannelNetworkingCommunity


  • 2.  Re: Fabric OS v.6.4.3b: long distance: why should I turn off DLS?

    Posted 09-08-2014 04:30 PM

    You shouldn't turn it off. I assume you use Exchange based routing which in that can on FOS 7 you cannot turn off DLS. On FOS 6 you had the option but in effect you should leave this on.

     

    I've written a piece on it here: http://erwinvanlonden.net/2014/01/dynamic-load-sharing-dls-and-in-order-delivery-iod/

     

    Hope this helps.

     

    Regards,

    Erwin


    #BrocadeFibreChannelNetworkingCommunity


  • 3.  Re: Fabric OS v.6.4.3b: long distance: why should I turn off DLS?

    Posted 09-08-2014 11:45 PM

    Hi Michael,

     

    please perform on both switches the command aptpolicy.

     

    I think you have exchanged based routing active on the V7.1.0c switch and port based on the V6.4.3b switch.

    When you have exchanged base routing you can not switch off DLS (both, V6 and V7), only when you have port based routing policy.

     

    Best practise is to have exchanged base routing active on all switches.

     

     


    #BrocadeFibreChannelNetworkingCommunity