Re: Show ip ospf statistics - Explanation

Hi,

You may find detailed explanation for the command output here

http://www.cisco.com/en/US/docs/ios/12_3t/ip_route/command/reference/ip2_s4gt.html#wp1167148

In short, Deta T shows how long ago from the current moment has the
particular SPF run started. Not sure about your IOS version number,
but on more recent boxes you will also see time for processing RIB
updates, i.e. time it takes to insert/remove prefixes from RIB after
SPF runs. It is important to realize that in larger networks the time
to update RIB is significantly higher than the time to run SPF/iSPF
algorithm.

As for tuning the throttle timers. Those affect SPF runs caused by
"fast" consequtive events, e.g. link flapping, normally happening
within intervals of seconds of milliseconds. Events of this type
normally generate "R"-type reasons inside area and get dampened
between areas thanks to summarization. The default SPF delay between
two consequtive events is 10 seconds, and you may notice that:

00:11:53 0 0 0 0 0 0 0 X
00:11:43 0 0 0 0 0 0 0 R, X

and

00:14:47 0 0 0 0 0 0 0 R, N
00:14:37 0 0 0 0 0 0 0 R

are most likely the result of SPF throttling.

HTH,

-- 
Petr Lapukhov, petr_at_INE.com
CCIE #16379 (R&S/Security/SP/Voice)
Internetwork Expert, Inc.
http://www.INE.com
Toll Free: 877-224-8987
Outside US: 775-826-4344
2010/2/22  <ccie_ka_at_gmx.de>:
> Hi,
>
> I confused about the output from "show ip statistics" !
>
> ##########################################################################
>
>            OSPF Router with ID (19.19.2.2) (Process ID 1)
>
>  Area 1: SPF algorithm executed 8 times
>
>  Summary OSPF SPF statistic
>
>  SPF calculation time
> Delta T   Intra D-Intra Summ    D-Summ  Ext     D-Ext   Total   Reason
> 00:21:58   0    0       0       0       0       0       0       R, SN
> 00:15:15   0    0       0       0       0       0       0       R
> 00:14:47   0    0       0       0       0       0       0       R, N
> 00:14:37   0    0       0       0       0       0       0       R
> 00:14:01   0    0       0       0       0       0       0       R, N
> 00:12:45   0    0       0       0       0       0       0       X
> 00:12:24   0    0       0       0       0       0       0       X
> 00:11:53   0    0       0       0       0       0       0       X
> 00:11:43   0    0       0       0       0       0       0       R, X
> 00:05:10   0    0       0       0       0       0       0       R
> #########################################################################
>
> Can anyone explane what does it mean with the "Delta T" column ?
> What is exactly 00:21:58 ->
>
> Is there any way to effect this output through the "timers throttle x x x " command ?
>
> Thanks to all..
>
> Regards
>
> Dennis
> --
> NEU: Mit GMX DSL |ber 1000,- ? sparen!
> http://portal.gmx.net/de/go/dsl02
>
>
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