What model/mfg. is the CSU/DSU?? Just curious, that's all. :)
Have a great Weekend to all!
Mark
-Original Message-
From: Michael Williams [mailto:[EMAIL PROTECTED]]
Sent: Friday, September 06, 2002 8:28 AM
To: [EMAIL PROTECTED]
Subject: Re: serial interface down/down or up/do
This just happened to me today. We had a point to point T1 circuit go down,
and all I could see on the one end was:
DCD=down DSR=up DTR=up RTS=up CTS=up
So, even though our CSU/DSU was powered up and connected to the routers
serial interface with a good cable, we showed DCD down because the
t have to be treated seperately from the the one involving
a
> >mere serial interface, due to the lack of interaction with an external
> >device for those functions.
> >
> >The two references that dramatically increased my understanding of layer
1
> >operations are the
e 3160 manual and uyless s black's Physical Layer
>Interfaces and Protocols book.
>
>
>- Original Message -----
>From: "Priscilla Oppenheimer"
>To:
>Sent: 21 June 2002 8:02 pm
>Subject: Re: serial interface down/down or up/down [7:47101]
>
>
> &g
ally increased my understanding of layer 1
operations are the paradyne 3160 manual and uyless s black's Physical Layer
Interfaces and Protocols book.
- Original Message -
From: "Priscilla Oppenheimer"
To:
Sent: 21 June 2002 8:02 pm
Subject: Re: serial interface down/down
Hi Everyone, I am new to this group and I just passed my CCIE written and am
looking forward to participating.
I have done a lot of lease line installs the last couple of years, and I
have worked with EIA-530, V.35, G.703, EIA-232 etc...Most of these installs
required me to go through an addition
At 07:17 PM 6/21/02, Chuck wrote:
>""Priscilla Oppenheimer"" wrote in message
>[EMAIL PROTECTED]">news:[EMAIL PROTECTED]...
> > I guess the question is too hard for a practice test if NOBODY can answer
> > it!?
> >
>
>CL: surprise surprise we all THINK we know the answer byt realy we don't ;->
M
iving keepalives...
Talk about a condition to make you scratch your head...
Thanks
Larry
-Original Message-
From: Howard C. Berkowitz [mailto:[EMAIL PROTECTED]]
Sent: Friday, June 21, 2002 10:23 AM
To: [EMAIL PROTECTED]
Subject: Re: serial interface down/down or up/down [7:47101]
I
""Priscilla Oppenheimer"" wrote in message
[EMAIL PROTECTED]">news:[EMAIL PROTECTED]...
> I guess the question is too hard for a practice test if NOBODY can answer
> it!?
>
CL: surprise surprise we all THINK we know the answer byt realy we don't ;->
> Here's the thing: Cisco says that a down/d
I've seen both down/down and up/down in real-world scenarios. The
difference between the two seemed to be the intelligence of the CSU/DSU.
With a recent Adtran unit, it goes down/down - if the CSU is down, it
takes down the DSU. I did not delve into the configuration to see if
this behavior cou
age-
> From: Priscilla Oppenheimer [mailto:[EMAIL PROTECTED]]
> Sent: Friday, June 21, 2002 2:08 PM
> To: [EMAIL PROTECTED]
> Subject: Re: serial interface down/down or up/down [7:47101]
>
>
> At 01:42 AM 6/21/02, John Neiberger wrote:
> >This isn't quite true.
ere 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.
>
>- Original Message -
>From: "Priscilla Oppenheimer"
>Newsgroups: groupstudy.cisco
>Sent: Thu
The interface ends up being down/down if encoding and framing are
misconfigured on the CSU/DSU? Sorry, you weren't clear about that part
which is the part I'm desperately trying to confirm. ;-) Thanks.
Priscilla
At 09:53 PM 6/20/02, itsme wrote:
>Hi Priscilla,
>
>I have actually had this scen
I guess the question is too hard for a practice test if NOBODY can answer
it!?
Here's the thing: Cisco says that a down/down interface means the router
interface is not sensing a Carrier Detect signal (that is, the CD is not
active).
Now, from my studies of V.35 I know that data carrier detect
At 01:42 AM 6/21/02, John Neiberger wrote:
>This isn't quite true.
I agree. I think the materials Michael was looking at overgeneralized.
Words like "only" and "always" just don't come into play with networks
unless you're talking about the speed of light or something. ;-)
Seriously, this much
I have seen down/up, but this was on xGS routers around release 9.x.
In those cases, it meant there was a main processor hardware (or
rarely software) failure.
Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=47139&t=47101
--
FA
EMAIL PROTECTED]
Subject: serial interface down/down or up/down [7:47101]
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 goo
I would add a mismatch encap to that list.
HDLC on one side and PPP on the other with show up/down.
Don
- Original Message -
From: "Tim Potier"
To:
Sent: Friday, June 21, 2002 10:15 AM
Subject: Re: serial interface down/down or up/down [7:47101]
> I have found
I have found a good bit of conflicting information on the causes of
down/down and up/down. All agree that down/down can be caused by:
1. no cable connection
2. CSU/DSU powered down
Some other reasons, although not consistently referenced in the literature
are:
1. Faulty cable (may also cause up/d
Ok, I have a backup frame relay that I can test on. Here's my findings:
I have an Excalibur ISX5311 connected to a 7206VXR. We have a full T to the
frame using ESF framing. The line is up/up. I modified the framing to D4
(there appears to be no SF?), and checked the line. It went down/down.
would somebody just change some settings on an external CSU/DSU and report
the results? Who cares if it's a production network? It's getting towards
midnight, it'll only take a couple of minutes, and the suits are all asleep!
;->
""John Neiberger"" wrote in message
[EMAIL PROTECTED]">news:[EMAI
This isn't quite true. For example, a DCE router interface will be
down/down if DTR is not raised by the DTE device. I see this quite
often at work and faulty cabling is generally not the culprit. It's
almost always bad hardware in the DTE.
John
Michael L. Williams wrote:
> According to CC
At 11:11 PM -0400 6/20/02, Bob Timmons wrote:
>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 th
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]">n
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
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 t
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 be
27 matches
Mail list logo
