Someone at Cisco was just telling me about a guy who came in from Korea to take the CCIE lab and during lunch, he called TAC on one of the problems. The TAC tech recognized the problem as a lab problem from his CCIE test, called down to the lab instructors to see if that person was taking the lab, and sure enough he was. He was busted and sent back home. I don't agree with what he did, but I find it amusing none the less.
""Steven A. Ridder"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > Thanks. > > > ""Priscilla Oppenheimer"" wrote in message > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > Yes, it's in IEEE 802.3. It's in Clause 28 of the IEEE 802.3 2000 Edition. > > It might have been in earlier versions too. > > > > Priscilla > > > > At 02:31 PM 12/31/01, Steven A. Ridder wrote: > > >Is there any standardization for autonegotiation like 802.x or something. > I > > >have never heard of anything like it, and maybe that's half the problem? > > > > > > > > >""Priscilla Oppenheimer"" wrote in message > > >[EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > > > Auto-negotiation is infamous for not working as advertised! ;-) It's > not > > > > just Cisco equipment. > > > > > > > > There is definitely a problem when introducing older 10BaseT equipment > > >into > > > > the equation, which it sounds like Ole did. Perhaps one of the more > > > > hardware, physical-layer type engineers remembers more of the details > > than > > > > I do, but from what I understand the 100-Mbps fast link pulses used > for > > > > auto-negotiation produce enough signal in the frequency band of the > > >10-Mbps > > > > link pulses such that the 10-Mbps chip thinks it sees a signal and > > doesn't > > > > re-negotiate or drop or establish link integrity as it should. > > > > > > > > It's definitely strange that STP noticed a problem when other > > applications > > > > didn't. I'll have to ponder that one...... > > > > > > > > Priscilla > > > > > > > > > > > > At 10:26 AM 12/31/01, [EMAIL PROTECTED] wrote: > > > > >It's been more than once when I've encountered > autonegotiation/autosense > > > > >issues between a Cisco router and Cisco switch. I've even seen > problems > > > > >when both interfaces were 10/100 and both hard-coded to 100/full and > the > > > > >link wouldn't come up. This may a chink in the Cisco armor as I > rarely > > > > >encounter issues with autonegotiation/autosense with other equipment > but > > > > >when I install a new Cisco network, one thing I ALWAYS have to do is > go > > > > >through the 10/100 ports of every switch and look for duplex (and > > >sometimes > > > > >speed) mismatches. Crazy... > > > > > > > > > >Rik > > > > > > > > > >-----Original Message----- > > > > >From: Kane, Christopher A. [mailto:[EMAIL PROTECTED]] > > > > >Sent: Saturday, December 29, 2001 11:02 PM > > > > >To: [EMAIL PROTECTED] > > > > >Subject: RE: Autosense this ... (add to your knowledgebase) [7:30446] > > > > > > > > > > > > > > >It's unfortunate that sometimes when things break, they don't perform > in > > > > >expected ways. Rather it truly was an Autosense problem or not, who > > >knows. > > > > >But it brings up a chance to talk about Autosense. I've had it bite > me > > >more > > > > >than once. I've had problems with Autosense that didn't show up until > > >months > > > > >after installation. It doesn't matter if its Cisco to Cisco or Cisco > to > > > > >another vendor, I've had to lock down ports at certain speeds and > modes > > >to > > > > >solve problems on several occasions. Just to pass along some > experience, > > >you > > > > >may always be better off hard setting your options. Nice persistence > Mr. > > > > >Jensen, it's cool to stick with something until you can make it work. > > > > > > > > > >Chris > > > > > > > > > >-----Original Message----- > > > > >From: Chuck Larrieu [mailto:[EMAIL PROTECTED]] > > > > >Sent: Saturday, December 29, 2001 6:14 PM > > > > >To: [EMAIL PROTECTED] > > > > >Subject: Re: Autosense this ... (add to your knowledgebase) [7:30446] > > > > > > > > > > > > > > >An interesting read, particularly since I am reviewing Kennedy > clark's > > >cisco > > > > >Lan Switching book prior to reviewing Cat5K and Cat 3920 > configuration. > > > > > > > > > >I am somewhat surprised at both the phenomenon and the concludion. > > >Spanning > > > > >tree blocks for particular reasons. > > > > > > > > > >when you concluded that your configurations were identical at all > > >offices, > > > > >does that mean that your port negotiations were set to auto > everywhere > > >else? > > > > >both on the routers and on the local switches? if so, I would expect > to > > >see > > > > >similar problems elsewhere. > > > > > > > > > >is it possible that there was a duplicate mac someplace in another > part > > >of > > > > >the bridged network, one that was being picked up by STP and > interpreted > > >as > > > > >a loop? You mention changing macs of interfaces as part of your > > > > >experimentation. Are you certain that this process was not part of > the > > > > >solution? > > > > > > > > > >To be frank, I'm hard pressed to come up with a reason why the FE > port > > on > > > > >the router would go into blocking. I can see that hapening on the > serial > > > > >port for reasons that have been discussed on this group in the past. > I > > >can't > > > > >come up with a rationale as to why hard setting of speed and duplex > > would > > > > >make a difference. I suppose one MIGHT conclude that if the port is > in > > >full > > > > >duplex, the STP process MIGHT see a loop occuring over the two > different > > > > >wire pairs. that's about the only wild rationale I can come up with. > And > > > > >that one is really stretching the point / bug / whatever. > > > > > > > > > >In any case, thanks for the good read. > > > > > > > > > >Chuck > > > > > > > > > > > > > > >""Ole Drews Jensen"" wrote in message > > > > >[EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > > > > > After a fun evening last night, I have decided not to trust the > > > > >autosensing > > > > > > on ethernet interfaces anymore. > > > > > > > > > > > > I was at a branch office where the users could not access the > > > > > > corporate network. The router, a 1720 setup as a bridge with the > same > > > > > > IP address for the FastEthernet as the Serial subinterface, both > > > > > > configured for bridge-group 1. It was connected to a 2620 at the > > > > > > corporate office via a Fractional Frame Relay connection. > > > > > > > > > > > > I changed the switch out with an old spare hub I had lying around, > > and > > > > > > connected only one workstation from the local network. After > starting > > > > > > the router up, I could ping the local workstation, and I could > ping > > > > > > devices on the corporate network, so both my FastEthernet and > Serial > > > > > > interfaces were working fine. However, I could not ping anything > on > > > > > > the corporate network from my workstation, nor could I from a > telnet > > > > > > connection to my corporate router ping the workstation, so traffic > > was > > > > > > not being passed through > > > > >between > > > > > > the interfaces. > > > > > > > > > > > > That looked like a typical routing problem, but the only problem > was > > > > > > that > > > > >I > > > > > > was not routing, I was bridging, so ????? > > > > > > > > > > > > I did a "show bridge 1 group" and saw that the FastEthernet was in > a > > > > > > blocking state by the spanning tree, so something was wrong here. > I > > > > >cleared > > > > > > the arp table on the router and on all other routers and switches. > I > > > > > > tried to assign a different mac address to the FE interface. I > tried > > a > > > > > > different workstation. No matter what I did, it kept being in a > > > > > > blocking state. > > > > > > > > > > > > I went in and did a "bridge-group 1 spanning-disabled" on the > > > > > > interface, > > > > >and > > > > > > it changed to forwarding state, but I could still not pass traffic > > > > >through. > > > > > > > > > > > > This is when I called TAC, but after I guided them through to a > > telnet > > > > > > connection to my routers, they decided after three hours that > > > > > > something weird was going on with the router, and they did an RMA > for > > > > > > a replacement unit. > > > > > > > > > > > > However, I decided to continue my troubleshooting, because I hate > to > > > > > > give up. I reconfigured everything, I tried to create a > bridge-group > > 2 > > > > > > instead, > > > > >I > > > > > > forced it into IP routing, and back off it again, but no matter > what, > > > > > > it kept going into blocking mode (I had removed the > spanning-disabled > > > > > > command again at that time). > > > > > > > > > > > > That's when it hit me to try and force the speed on the interface. > It > > > > > > was > > > > >in > > > > > > AUTO, and my switch had been auto 10/100, but my hub was only 10. > I > > > > >changed > > > > > > it from auto to 10 and power cycled the router. PLING!!! Now it > > > > > > started up and after the listening and learning, it went in > > forwarding > > > > > > state, and I could now ping through my router, and I could connect > my > > > > > > workstation to > > > > >the > > > > > > corporate network. > > > > > > > > > > > > What makes this strange is that I can apparently use my > FastEthernet > > > > > > interface from the router even though the speed is wrong, but the > STP > > > > >see's > > > > > > this and blocks the interface for switched traffic. WEIRD!!!!! > > > > > > > > > > > > Read the entire case study here: > > > > > > > > > > > > http://www.RouterChief.com/CaseStudies/1.htm > > > > > > > > > > > > Ole > > > > > > > > > > > > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > > > > > Ole Drews Jensen > > > > > > Systems Network Manager > > > > > > CCNP, MCSE, MCP+I > > > > > > RWR Enterprises, Inc. > > > > > > [EMAIL PROTECTED] > > > > > > http://www.RouterChief.com ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > > > > > NEED A JOB ??? > > > > > > http://www.oledrews.com/job > > > > > > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > > > > > > > > > > > > > > > > ________________________ > > > > > > > > Priscilla Oppenheimer > > > > http://www.priscilla.com > > ________________________ > > > > Priscilla Oppenheimer > > http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=30663&t=30446 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
