Personally speaking, I try to stick to it as well. I've noticed more wonky things the more environments diverge from it. Technically speaking, that should not make sense - but this an unqualified opinion of mine.
-- Espi On Fri, Sep 20, 2013 at 11:59 AM, Michael B. Smith <mich...@smithcons.com>wrote: > I still use it.**** > > ** ** > > Violate the rule at your peril. :P**** > > ** ** > > *From:* listsad...@lists.myitforum.com [mailto: > listsad...@lists.myitforum.com] *On Behalf Of *Jonathan Link > *Sent:* Friday, September 20, 2013 2:07 PM > > *To:* ntsysadm@lists.myitforum.com > *Subject:* Re: [NTSysADM] Semi-OT: Network problem**** > > ** ** > > Is this the equivalent of Vader saying "Your powers are weak, old man" to > Obi Wan?**** > > ** ** > > On Fri, Sep 20, 2013 at 1:55 PM, Kurt Buff <kurt.b...@gmail.com> wrote:*** > * > > Sigh. Yes, but... > > "The 5-4-3 rule was created when 10BASE5 and 10BASE2 were the only > types of Ethernet network available. The rule only applies to > shared-access 10 Mbit/s Ethernet backbones. The rule does not apply to > switched Ethernet because each port on a switch constitutes a separate > collision domain." > > :) > > Kurt > > On Fri, Sep 20, 2013 at 10:37 AM, Michael B. Smith > <mich...@smithcons.com> wrote: > > http://en.wikipedia.org/wiki/5-4-3_rule > > > >**** > > > -----Original Message----- > > From: listsad...@lists.myitforum.com [mailto: > listsad...@lists.myitforum.com] On Behalf Of Kurt Buff**** > > > Sent: Friday, September 20, 2013 12:59 PM > > To: NTSysADM@lists.myitforum.com > > Subject: [NTSysADM] Semi-OT: Network problem > > > > All, > > > > In the past couple of weeks, $work has had a problem with network > interruptions - frequent gaps in network connectivity were all contact is > lost with servers for brief periods of time (1-2 minutes, usually). > > > > I could see the gaps in the graphs on my (very new and incomplete - long > story, don't ask) cacti installation. Unfortunately, I've been unable to > get cacti to graph CPU utilization for the switches, because they're > Procurves, and I couldn't find a working XML file or configuration for that. > > > > It's always happened while I've been unavailable, until today. > > > > Just now, I was able to show conclusively that our core layer3 switch > (Procurve 3400cl-48G), which was hit hardest, spikes its CPU to 99% during > these episodes. Volume of traffic is normal - ho huge spikes in that, just > normal variation, AFAICT, from the cacti graphs. I haven't had time to see > if other switches also spike their CPU, but given the gaps in the graphs, I > suspect that's the case. > > > > I suspect someone is doing something stupid to create layer2 loop, as we > have lots of little 5 and 8 port switches on desktops and in our > engineering lab - and in spite of the fact that I've set our core switch as > the root of the spanning tree. > > > > I'm setting up a box to do a tcpdump in a ring buffer with smallish > files so that I can do analysis on them more easily. > > > > I'm not a packet analysis guy, though I've done some looking on occasion. > > > > Anyone have thoughts on what to look for when I start my analysis? > > > > Kurt > > > > > > **** > > ** ** >
