I work at firm that transfers files some being up to 6Gb and growing to a network server that is dedicated to storing the files.

These files are compared after transfer by a comparison software that sits on the source machine. So it must compare the files over the network connection. There can be a few devices writing or reading from the machine not more than 6 simultaneously.

So I will look at what HDDs on the server to see if they are the best. I am guessing that will be the biggest bottle neck, but can I help by putting all my machines on separate VLANs to reduce the size of their broadcast domain or will that give no appreciable increase in performance? The devices are on a Cisco 2970X-TS24, and access the network through through a Cisco ASA 5525-X.

  • What is the uplink to access port bandwidth ratio? If the uplink port speed matches the access port link speed, one device could theoretically monopolize the uplink. You want to look at the bandwidth in the path links to look for bottlenecks before you worry much about the, apparently small, broadcast domain.
    – Ron Maupin
    Nov 15, 2015 at 21:36
  • Ill check that now Ron
    – DavyGravy
    Nov 18, 2015 at 6:44

1 Answer 1


Generally speaking, unless you have a large broadcast domain (hundreds of hosts) with lots of broadcast traffic, simply isolating the traffic to a VLAN won't help you much.

I'm not finding specs for a Cisco 2970X, are you sure it isn't a 2970G or 2960X? Either way, it looks like you're working with 1gbps ports

Things I would look at first:

  1. Are you getting 70-80MB/s transfer rate from your client machines? Yes: Congrats, you've reached optimal transfer rates for your link speed, look into 10gbps or port channels all around for additional throughput. If not, continue:
  2. Are you maxing out the server interface? Yes: Your server interface is the bottle neck, if you have an additional interface on the server look into setting up an LACP bond with two NICs to your switch for 2gbps throughput. If not, continue:
  3. Check your intermediate uplinks between network devices, if you're maxing these out, I'd suggest putting an extra link in there for additional bandwidth, again look into LACP port channels between your 2970 and your ASA. If not:
  4. At this point it doesn't appear to be a congestion issue. Other bottlenecks might be the ASA (if too many rules or filters are applied), or disk IO
  • Super jbain ill try these things
    – DavyGravy
    Nov 18, 2015 at 6:46

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