RE: OT: When to upgrade bandwidth?

Clear your counters, 14 weeks and 186 interface resets is fairly bad. Your reliability should remain at 255/255 unless there are line troubles.

It's hard to tell by the counters how many of the errors came from normal traffic times vs interface resets. When the interface resets, you'll usually get a couple hundred errors. If after you clear the counters you're still getting incrementing errors, you should have a ticket opened. You could also use some form of historical reporting, both for errors and input / output readings. I would suggest using Cacti to monitor the router via SNMP, should give you a clearer picture of what's happening during complaint times.

-ryan

-----Original Message-----
From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of Haroon
Sent: Wednesday, October 07, 2009 12:39 PM
To: garry baker
Cc: Cisco certification
Subject: Re: OT: When to upgrade bandwidth?

Hi Garry,

Thanks for the reply. Most of the traffic is email (exchange server,
webmail), http, VPN tunnels, microsoft-ds (active dirctory) so all of it is
needed. Slow means the users complain... The connection is fast (t1
connection speeds) when there is little or no traffic. Here is output from
the show interface on serial on a 2821:

Serial0/2/0 is up, line protocol is up
  Hardware is GT96K with integrated T1 CSU/DSU
  Internet address is 12.12.12.12/30
  MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,
   * reliability 255/255, txload 65/255, rxload 183/255
* Encapsulation PPP, LCP Open
  Listen: CDPCP
  Open: IPCP, loopback not set
  Keepalive set (10 sec)
  Last input 00:00:13, output 00:00:09, output hang never
  Last clearing of "show interface" counters 14w2d
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 103131
  Queueing strategy: weighted fair
  Output queue: 0/1000/64/99613 (size/max total/threshold/drops)
     Conversations 0/64/256 (active/max active/max total)
     Reserved Conversations 0/0 (allocated/max allocated)
     Available Bandwidth 1158 kilobits/sec
  5 minute input rate 1111000 bits/sec, 189 packets/sec
  5 minute output rate 394000 bits/sec, 167 packets/sec
     454757217 packets input, 3768278802 bytes, 0 no buffer
     Received 0 broadcasts, 0 runts, 301 giants, 0 throttles
* 280932 input errors, 280932 CRC, 134763 frame, 88871 overrun, 0
ignored, 121798 abort
     428469700 packets output, 315029173 bytes, 0 underruns*
     0 output errors, 0 collisions, 186 interface resets
     0 output buffer failures, 0 output buffers swapped out
     304 carrier transitions
     DCD=up DSR=up DTR=up RTS=up CTS=up

What concerns me is the input and CRC errors... I've had the line tested
couple of times and there are no issues with it so it must be
receiving/sending more traffic than the connection allows? Also, when I
download something from remote sites or even from the internet, the *
reliability* figures spike up, never seen that happening on a T1.

Thanks,

Haroon

On Wed, Oct 7, 2009 at 12:12 PM, garry baker <baker.garry_at_gmail.com> wrote:

> do you have any methods of QoS on these links?
>
> which specific applications are slow? and does slow mean they do not work
> or do users complain?
>
> What traffic is causing these 95th % spikes and for how long are they
> sustained? Can you get rid of this traffic? Or police down so the other
> 'mission critical' traffic can utilize these spikes of bandwidth?
>
> if you have the money to spend why not more bandwidth is never a bad thing,
> but not always the correct answer either...
>
> you say the connection is 'slow' to the Internet, is it fast when your
> monitoring tools say there is no traffic on your T1 or is this a contention
> ratio issue with your ISP to the "Internet"?
>
> HTH,
>
> thanks..
> garry..
>
> On Wed, Oct 7, 2009 at 6:23 PM, Haroon <itguy.pro_at_gmail.com> wrote:
>
>> Hi Experts,
>>
>> Is there a golden rule as to when an organization should do bandwidth
>> upgrade? We have a few T1s that we use for different purposes and on one
>> of
>> them I have seen increased utilization and often the connection is slow
>> (to
>> the internet). I am using netflow, Netflow analyzer Pro to collect the
>> data.
>>
>> How many "Ws" should I see in the graphs consistently before considering
>> bandwidth upgrade or move certain services to another T1? How many spikes
>> into the 95th percentile utilization should there be per day, week, month?
>>
>> We have 4 (maybe more later) site to site VPNs (to a concentrator) for our
>> remote locations, about 100 employees all together.
>>
>> I personally, would like to move the VPNs, etc. to a dedicated T1.
>>
>> Thanks,
>>
>> Haroon
>>
>>
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>>
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>
>
> --
> Garry L. Baker
>
> "There is no 'patch' for stupidity." - www.sqlsecurity.com

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Received on Wed Oct 07 2009 - 13:37:31 ART