Problem: Delayed server response to client activity

Causes

Possible causes are:

  • a congested LAN

  • improperly sized platforms

Using the netstat command on the client may help troubleshoot network throughput problems. When an Ethernet LAN is highly congested, the actual throughput slows down. This is caused by packets colliding on the LAN as multiple machines begin to transmit at approximately the same time, for example, when multiple GUI or OSS clients are performing tasks simultaneously.

Steps
 
1 

Client GUIs may respond more slowly than normal during resynchronizations of managed devices. Repeat the client GUI action when the resynchronization is complete.

2 

Check for LAN throughput issues.

  1. Open a shell console window.

  2. Enter the following at the console prompt to display local network-interface transmission data over a period of time:

    # netstat -i s ↵

    where s is the time, in seconds, over which you want to collect data. Nokia recommends that you start with 50 s

  3. Review the output. The following is sample netstat output:

    netstat -i 5
 input   le0       output          input  (Total)    output
packets errs  packets errs  colls packets errs  packets errs  colls
6428555 41    541360  80    49998 6454787 41    567592  80    49998
22      0     0       0     0     22      0     0       0     0
71      0     7       0     3     71      0     7       0     3

    This sample displays the number of input and output packets, errors and collisions on the le0 interface. One column displays the totals for all interfaces. This sample only has one interface, so both sets of columns display the same data.

    Calculate the number of collisions as a percentage of the number of output packets. For example, according to the last line of output, there were three collisions and seven output packets resulting in a 42% rate.

    This number is high, but the time in which the sampling was obtained (5 s), was low. Change the sample rate to, for example, 50 s for an accurate sampling of the network throughput.

    When collisions are between 2% and 5%, congestion on the interface is within the normal operating range.

    In a typical network, when collisions are greater than 5%, you may have a serious congestion problem on the interface. Review your LAN topology and design to reduce the number of network bottlenecks.

  4. To stop the command, press Ctrl-C.

3 

Check that the server and client platforms are appropriately sized. See the NSP Planning Guide for more information.

End of steps