According to CCIE exam materials, the *only* time the serial will show down/down is when there is NO serial cable or a bad serial cable connected. So even if you have a misconfigured framing method, you should at least see up/down.....
Mike W. "Bob Timmons" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > I can't say I've ever seen a down/up condition. Up/Down perhaps. > > I'm sure there are exceptions, but it's my belief that the router doesn't > care about encoding, but rather a layer-1 connection to the dce/dte device. > If the router can 'talk' to the device on the other end of the cable, you > should get an up/x condition, where x would depend on the csu/dsu condition > of the line. > > I don't have a csu handy, otherwise I'd check that right now. I can do that > tomorrow morning (10:30 pm est here), but you may have an answer prior to > that... > > > > Hi Priscilla, > > > > I have actually had this scenario (multiple times), but due to the Telco's > > misconfiguration. > > Specifically we were expecting b8zs/esf. Unfortunately I can't confirm > > which was configured incorrectly, but I can confirm that going through > > all of the different combinations available at the router you will > > get all combinations on the serial interface (up/up, down/up and > down/down). > > > > I can also confirm, you will not establish connectivity, regardless. I > > believe > > either b8zs/esf or sf/ami are the only valid combinations. At least that > is > > all I've > > ever worked with. > > > > Hope this helps, > > -TV > > > > > > ""Priscilla Oppenheimer"" wrote in message > > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > > Hi Group Study, > > > > > > While writing some questions for a practice test, I found myself > > > questioning what I thought was the right answer. Here's the scenario: > > > > > > A Cisco router serial interface is correctly connected with a good V.35 > > > cable to the data port on the DSU side of a CSU/DSU. The CSU/DSU has > been > > > misconfigured for the framing method (SF instead of ESF). The framing > > > doesn't match what the provider is using. (The question refers to a > > CSU/DSU > > > that is external to the router, not one that is built into the router.) > > > > > > Will the Cisco router serial interface be down/down or up/down? > > > > > > And, would the answer be any different if the question has to do with > > > misconfiguring the encoding (AMI versus B8ZS)? > > > > > > If you have real-world experience with this, that would help. I have > read > > > the Cisco documentation and the troubleshooting charts, etc. > > > > > > Thanks > > > > > > Priscilla > > > > > > ________________________ > > > > > > Priscilla Oppenheimer > > > http://www.priscilla.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=47111&t=47101 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
