[nsp] Traffic issues (ethernet)

[Barry Kiesz]

I've been doing a little research on Cisco's site about this, but really
haven't found the answer I'm looking for. So I thought I'd give this
group a try since everyone here seems pretty knowledgeable when it comes
to 'real-life' networks.

Background info:
My problem is this:  I have a customer who is a wireless ISP (2.4G) and
were experiencing some interesting things.  It all started when I
attempted to install another router (Tasman... Not my decision) and
setup MLPPP over a few T1's.  Once I plugged that router in, certain
customers had trouble getting places, latency shot up, etc..  I traced
that and another issue to a bad NPE300 in my border 7204VXR (My Router).
I replaced my blade and attempted to hook the dual T1's up again.  Same
latency issue.  So I plugged our little 2501 back in.  But now it seems
that wasn't the only problem..

What I'm seeing now:
When I do a 'sh int e0' on the 2501 I'm getting after 18 hours

Ethernet0 is up, line protocol is up 
  Hardware is Lance, address is 0060.7015.91f6 (bia 0060.7015.91f6)
  Internet address is 64.68.166.1/24
  MTU 1500 bytes, BW 10000 Kbit, DLY 1000 usec,
     reliability 255/255, txload 12/255, rxload 6/255
  Encapsulation ARPA, loopback not set, keepalive set (10 sec)
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input 00:00:00, output 00:00:00, output hang never
  Last clearing of "show interface" counters 18:02:34
  Queueing strategy: fifo
  Output queue 0/40, 0 drops; input queue 58/75, 15335 drops
  5 minute input rate 265000 bits/sec, 353 packets/sec
  5 minute output rate 475000 bits/sec, 108 packets/sec
     21146452 packets input, 2189310135 bytes, 0 no buffer
     Received 425827 broadcasts, 0 runts, 0 giants, 15336* throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
     0 input packets with dribble condition detected
     10026909 packets output, 3786075904 bytes, 0 underruns
     0 output errors, 130056 collisions, 1 interface resets
     0 babbles, 0 late collision, 292668 deferred
     0 lost carrier, 0 no carrier
     0 output buffer failures, 0 output buffers swapped out

They also have a small dialup pool using a AS5248.  Here is the e0
output (16 hours):

Ethernet0 is up, line protocol is up 
  Hardware is Lance, address is 0010.7b14.4f58 (bia 0010.7b14.4f58)
  Internet address is 64.68.183.1/24
  MTU 1500 bytes, BW 10000 Kbit, DLY 1000 usec, rely 255/255, load 1/255
  Encapsulation ARPA, loopback not set, keepalive set (10 sec)
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input 00:00:00, output 00:00:00, output hang never
  Last clearing of "show interface" counters never
  Queueing strategy: fifo
  Output queue 0/40, 0 drops; input queue 6/75, 47102 drops
  5 minute input rate 73000 bits/sec, 27 packets/sec
  5 minute output rate 12000 bits/sec, 17 packets/sec
     1727769 packets input, 730101184 bytes, 46719 no buffer
     Received 590341 broadcasts, 0 runts, 0 giants, 47102 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
     0 input packets with dribble condition detected
     1373974 packets output, 189040619 bytes, 0 underruns
     0 output errors, 407 collisions, 94209 interface resets
     0 babbles, 0 late collision, 2874 deferred
     0 lost carrier, 0 no carrier
     0 output buffer failures, 0 output buffers swapped out

Here's a diagram of how it's setup:

Bridge system (all customers use 2501's GW address)
Wireless Radios are 10Mb connections
About 200 wireless subscribers

---------------   ---------------   ---------------  ---------------
-------- 
|WirelessRadio|   |Wireless Radio|  |Wireless Radio| |Wireless Radio|
|AS5248|
---------------   ---------------   ---------------- ---------------
--------
      |                  |                 |                |
|
      |                  |                 |                |
|
------------------------------------------------------------------------
--------
|                      100Mb Switch
|
|-----------------------------------------------------------------------
--------
                                      |
                                      |
                                      |
                                ------------------------
                                |NetEnforcer BW Manager|
                                ------------------------
                                      |
                                      |
                                      |
                                 -------------
                                 |Cisco 2501 |
                                 -------------

Possible solution:

Would physically segmenting the network help with this issue (reduce the
broadcasts to the 2501 and 5248)?
I was thinking about putting 2 wireless radios per switch, then
uplinking to a 3rd switch which has the 5248 on it. Then uplinking that
to the NetEnforcer, then to the 2501.


Any help or guidance would be appreciated as this is starting to be an
issue and my customer is getting frustrated, as so am I.

Thanks,

Barry