Slow network access

apakamachikezie · ‎02-07-2007

Hi,

I have 8 cisco 2950 switches connected in a star topology to another 2950 switch(B) which links the network to the 6509 swtch that we use as the core switch. Users are complaining of slow network response, but I have checked the switch for errors, duplex mismatches, etc and there is none. But I have pvst spanning-tree and portfast configured on all the ports that connect to the switches and users alike. Could this be the cause of the problem?

nyr.hakeem-habeeb · ‎02-07-2007

Hi,

can you paste the output of the "show interface" for the link between 2950(B) and the 6509?

Thanks.

HH

apakamachikezie · ‎02-07-2007

Hi,

Pls kindly find below the output for the 'show interface' for the link btw the 2950(B) and the 6509VRF switch.

2950(B)# sh int f0/24

FastEthernet0/24 is up, line protocol is up (connected)

Hardware is Fast Ethernet, address is 0013.1a2d.1058 (bia 0013.1a2d.1058)

Description: "6509VRF"

MTU 1500 bytes, BW 100000 Kbit, DLY 1000 usec,

reliability 255/255, txload 1/255, rxload 4/255

Encapsulation ARPA, loopback not set

Keepalive set (10 sec)

Full-duplex, 100Mb/s

input flow-control is off, output flow-control is off

ARP type: ARPA, ARP Timeout 04:00:00

Last input 00:00:26, output 00:00:01, output hang never

Last clearing of "show interface" counters 2w1d

Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0

Queueing strategy: fifo

Output queue: 0/40 (size/max)

5 minute input rate 1795000 bits/sec, 485 packets/sec

5 minute output rate 720000 bits/sec, 411 packets/sec

413006992 packets input, 4207145332 bytes, 0 no buffer

Received 1035741 broadcasts (0 multicast)

0 runts, 0 giants, 0 throttles

0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored

0 watchdog, 333929 multicast, 0 pause input

0 input packets with dribble condition detected

271035757 packets output, 839632979 bytes, 0 underruns

0 output errors, 0 collisions, 0 interface resets

0 babbles, 0 late collision, 0 deferred

0 lost carrier, 0 no carrier, 0 PAUSE output

0 output buffer failures, 0 output buffers swapped out

6509VRF#sh int f3/3

FastEthernet3/3 is up, line protocol is up (connected)

Hardware is C6k 100Mb 802.3, address is 0016.c885.0e3a (bia 0016.c885.0e3a)

Description: "2950(B)"

MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,

reliability 255/255, txload 9/255, rxload 4/255

Encapsulation ARPA, loopback not set

Keepalive set (10 sec)

Full-duplex, 100Mb/s

input flow-control is off, output flow-control is unsupported

ARP type: ARPA, ARP Timeout 04:00:00

Last input 00:00:55, output 00:00:54, output hang never

Last clearing of "show interface" counters never

Input queue: 0/2000/4175/0 (size/max/drops/flushes); Total output drops: 30212

2

Queueing strategy: fifo

Output queue: 0/40 (size/max)

5 minute input rate 1574000 bits/sec, 596 packets/sec

5 minute output rate 3703000 bits/sec, 821 packets/sec

1155768140 packets input, 263305008353 bytes, 0 no buffer

Received 12702138 broadcasts (7139310 multicasts)

0 runts, 0 giants, 0 throttles

0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored

0 watchdog, 0 multicast, 0 pause input

0 input packets with dribble condition detected

1785058839 packets output, 1075119494370 bytes, 0 underruns

0 output errors, 0 collisions, 3 interface resets

0 babbles, 0 late collision, 0 deferred

0 lost carrier, 0 no carrier, 0 PAUSE output

0 output buffer failures, 0 output buffers swapped out

6509VRF#

Many Thanks,

C

andreas.larsen · ‎02-07-2007

Is the slow "network" really the network to blame ? What is slow on the network ? Is the WINS servers responding properly, DNS servers ? If you could attach a diagram of your current network it would be valuable.

glen.grant · ‎02-07-2007

You should never have portfast on any attached "network" devices , should be used on client ports.

Danilo Dy · ‎02-07-2007

I think you did your assignment for errors, duplex, and speed.

In your "show int" output the load is not that high or you may have took the sample during non-peak hour? Do you have any utilities that captures bandwidth utilization of all ports specially the ports that connects Switch(B) and 6509 switch like MRTG? If historical data during the time the user complains slow network response has low bandwidth utilization, you may need to look at the host (or application) that user is accessing as bandwidth throughput is also controlled in the application level. If historical data shows differently (i.e congested) you may need to invest for GE between Switch(B) and 6509 or you can try channeling. Check also the servers and user system for viruses, in most cases this is the culprit.

mworkman · ‎02-07-2007

One thing I noticed you are using 100meg ports connected to your 6500 2950's and the 6500 have gig ports upgrade your connection to gig see if that helps. Also make sure you have good IOS, one other trick I learn with the 2950 they need to be reboot about 3 to 6 months... Good luck!!

apakamachikezie · ‎02-08-2007

Hi,

Users observe slow response assessing applications on the network.

Looking at Solarwinds, I observerd the following data for the last 7 days on the port connected to the 6509VRF switch:

2950(B): Max Rx utilization - 22% Max TX utilization :1.37% No interface errors and discards, for the last 7 days.....

6509VRF Switch: Transmit utilization for the last 7 days on the port linking the 2950(B) switch: 5.89% Rx utilization for the same port: 1.55%

However I noticed some interface deiscards on the 6509VRF switch on a daily basis. Pls see attached images.

Regards,

C.