[cisco-nas] Slips
Joseph Mays
jfmays at launchpad.win.net
Thu Oct 11 14:18:33 EDT 2012
This fixed it, thanks so much! We had the T1 controllers set to take clocking from the line on all the IAD2400's, but the interesting revelation is that setting the T1 clocking to line does not, itself, tell the IAD to take the clocking from the line. Not all the IAD's have two t1's, some only had one, they were also getting slips. We went to each of them, set "network clock participate" and "network clock select 0" on all of them, problem solved. No more slips.
----- Original Message -----
From: Aaron Leonard
To: Joseph Mays
Cc: cisco-nas at puck.nether.net
Sent: Wednesday, October 10, 2012 4:30 PM
Subject: Re: [cisco-nas] Slips
OK ... so I've never laid a finger on an IAD2400, but I cheated and looked at an old email from a knowledgeable source, and here's what he says (for the case where the IAD2400 is taking clock from one T1 and providing to another):
network-clock base-rate [56k | 64k ] as appropriate
network-clock-select 1 T1 [0 | 1 ] as appropriate
clock source line on the appropriate controller
clock source internal on the other controller
If the peer devices are providing clocking and accepting clocking as you've set
on the IAD, then you should get no slips.
Does this help?
Aaron
------------------------------------------------------------------------------
On 10/10/2012 12:57 PM, mays at win.net (Joseph Mays) wrote:
I have noticed something that I have not noticed prior to this, which is that all the units that are experiencing slips are IAD2400's All are set to get clocking from the line, but does the IAD2400 behave differently with regard to clocking than most things somehow?
----- Original Message -----
From: Aaron Leonard
To: Joseph Mays
Cc: cisco-nas at puck.nether.net
Sent: Wednesday, October 10, 2012 3:30 PM
Subject: Re: [cisco-nas] Slips
The pri-group config is weird, but I would not think it's relevant.
My theory continues to be, until disproven, that the device that is on the far side of the slipping span is not configured right.
--------------------------------------------------------------------------
On 10/10/2012 12:21 PM, mays at win.net (Joseph Mays) wrote:
Yeah. The DACS is not the problem though, because we have two circuits going through the DACS, in fact they are two circuits that are exactly the same, following the same path from our AS5400 through the telco to the same router (an IAD2400) at the same customer, one is getting slips one is not. Both go through the DACS. The only difference between them is that one has just a channel group for T1 service and the other has both a channel group and a PRI group. The one with just the channel group is plugged into the native T1 port on the IAD2400. The one with both is plugged into a card that will support multilple tdm groups on a card.
On the AS5400....
controller T1 1/0:22
framing esf
channel-group 0 timeslots 1-22 speed 64
description Glass Doctor combo PRI and T1 1
!
controller T1 1/0:23
framing esf
channel-group 0 timeslots 1-22 speed 64
pri-group timeslots 23-24
description Glass Doctor combo PRI and T1 2
The second one, on 1/0:23, gets slips about once every 10 seconds.
----- Original Message -----
From: Aaron Leonard
To: Joe Mays
Cc: cisco-nas at puck.nether.net
Sent: Wednesday, October 10, 2012 2:09 PM
Subject: Re: [cisco-nas] Slips
I suppose it is possible that a DACS could introduce enough jitter into the signal to keep the other system from deriving clock from the line. This is not a problem in the general case though.
----------------------------------------------------------------------
On 10/9/2012 9:31 PM, jfmays at launchpad.win.net (Joe Mays) wrote:
It has been suggested that if those circuits go through a DAX, the clocking signal may not be making it to the other system.
----- Original Message -----
From: Aaron Leonard
To: Joseph Mays
Cc: cisco-nas at puck.nether.net
Sent: Tuesday, October 09, 2012 7:00 PM
Subject: Re: [cisco-nas] Slips
The 5400 has only one clocking domain. So, if you are getting clock from slot 6 port 0, then this is the time source for the whole TDM bus. So, all other T1s on the 5400 will be synchronized to that source, and anything that takes clock from those T1s should be synchronized.
http://www.cisco.com/en/US/tech/tk713/tk628/technologies_tech_note09186a008014f8a6.shtml
That's why I suspect that the system on the other side of T1 6/1 is not actually taking clock from the line. Maybe it's free running or maybe it's taking clock from something else.
Aaron
------------------------------------------------------------------
On 10/9/2012 2:46 PM, mays at win.net (Joseph Mays) wrote:
I would like to change port 6/1 to clocking internal, but I can't find any way change the clocking on an individual t1 port controller to internal. Am I missing something?
----- Original Message -----
From: Joseph Mays
To: Aaron Leonard
Cc: cisco-nas at puck.nether.net
Sent: Tuesday, October 09, 2012 4:48 PM
Subject: Re: [cisco-nas] Slips
Thank you for your response.
Show tdm clocks shows the AS5400 is using the circuit in port 6/0 for primary clocking.
Primary Clock:
--------------
System primary is slot 6 port 0 of priority 1
TDM Bus Master Clock Generator State = NORMAL
Backup clocks for primary:
Source Slot Port DS3-Port Priority Status State
-------------------------------------------------------------
Trunk 1 1 YES 2 Good Configured
Trunk 1 2 YES 3 Good Configured
Trunk 1 3 YES 4 Good Configured
Trunk 1 4 YES 5 Good Configured
Trunk 1 5 YES 6 Good Configured
Trunk 6 1 NO 213 Good Default
Trunk 1 28 YES 202 Good Default
Trunk 1 27 YES 203 Good Default
Trunk cards controllers clock health information
------------------------------------------------
CT3 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
Slot Port Type 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1
1 0 T3 G G G B B G G B B G B G B B B B B B B B B B B G G G G G
We had considered the possibility that the problem might be coming from the mux that everything was passing through. I rewired the pinouts from telco in order to connect them directly to a t1 port on the AS5400 (Controller 6/1), rather than passing them through the mux and coming across a channel on the t3. It works, but the slips are exactly the same.
ArmoryPl-AS5400#show controller t1 6/1
T1 6/1 is up.
Applique type is Channelized T1
Cablelength is long gain36 0db
Description: Leonard Brush MUX Bypass
No alarms detected.
alarm-trigger is not set
Version info of slot 6: HW: 768, PLD Rev: 1
Framer Version: 0x8
Manufacture Cookie Info:
EEPROM Type 0x0001, EEPROM Version 0x01, Board ID 0x02,
Board Hardware Version 3.0, Item Number 73-3996-03,
Board Revision A0, Serial Number JAB044106K3,
PLD/ISP Version <unset>, Manufacture Date 11-Oct-2000.
Framing is ESF, Line Code is B8ZS, Clock Source is Line.
Data in current interval (638 seconds elapsed):
0 Line Code Violations, 0 Path Code Violations
54 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins
54 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail Secs
Right next to it is the trunking circut plugged into 6/0, it runs fine, no slips. I would like to change 6/1 to internal clocking, btw, so that it should be following the clock that is being derived on 6/0, but can't find anyway to change that on the t1 ports. So as it stands right now, both 6/1 and the customer router on the other end of that t1 are set to clock-source line, with no mux between them. And getting slips.
----- Original Message -----
From: "Aaron Leonard" <Aaron at cisco.com>
To: "Joseph Mays" <jfmays at launchpad.win.net>
Cc: <cisco-nas at puck.nether.net>
Sent: Tuesday, October 09, 2012 3:21 PM
Subject: Re: [cisco-nas] Slips
> Joe,
>
> Sounds like, conceptually, you've set things up right. I would
> doublecheck on the customer routers to make sure that they really are
> taking clock from the right T1 line.
>
> On the 5400, you should be using "tdm clock priority" to set the clock
> source, and "show tdm clocks" to validate the clocking.
> http://www.cisco.com/en/US/docs/ios/12_3/dial/command/reference/dia_s6g.html#wp1140246
>
> Aaron
>
> ----
>
> On 10/9/2012 8:43 AM, jfmays at launchpad.win.net (Joseph Mays) wrote:
>> It occurs to me that there is an assumption built into this that is
>> unproven. Does setting the AS5400 to internal clocking on the T3 cause it to
>> provide clocking for the T1's on the T3? We have assumed that it does. If
>> not, how do we tell it to provide an outgoing clock signal for the T1's on
>> the T3?
>>
>> ----- Original Message -----
>> From: "Joe Mays" <mays at win.net>
>> To: "cisco-nsp" <cisco-nsp at puck.nether.net>; <cisco-nas at puck.nether.net>
>> Sent: Tuesday, October 09, 2012 12:57 AM
>> Subject: [cisco-nas] Slips
>>
>>
>>> We have an AS5400 that we are using to provide PRI's to customers. It has
>>> the following circuits coming into it from the Telco (AT&T).
>>>
>>> 5 Trunking circuits that come across T1 ties into a t3 mux, and then are
>>> then delivered to a T3 port on the AS5400. ! trunking circuit that is
>>> connected into a T1 card on the AS5400. Several circuits to customers that
>>> are delivered out of the T3 through the mux to T1 tie pairs through AT&T,
>>> and some of which go through HDSL T1's that we provide.
>>>
>>> We have clocking set up thusly. The T1 port that has the trunk line in it
>>> (Serial6/0) is set to clock source line, to get clocking from AT&T.
>>> The TDM clock priority on AS5400 is set to Serial6/0.
>>> The T3 that has all the other T1's is set to clock source internal, on the
>>> assumption that the internal clock on the AS5400 should now be
>>> synchronizing to the trunk line coming in on 6/0. So all the T1 channels
>>> on the T3 should be following the Cisco clock.
>>> The mux is set to clocking is set on the t3 to clock source line, to get
>>> clocking from the T3 coming from the AS5400.
>>> The customers at the end are all set to clock source line.
>>>
>>> None of the trunks is having slips, but several of the AT&T customers are
>>> showing a slip every 10 seconds or so. The clocking chain we have set up
>>> seems logical to me. Is there something I'm missing? Why would the
>>> customers be having slips.
>>>
>>> We asked AT&T to monitor one of the lines that we are seeing slips on.
>>> They watched it for a bit and said no slips are occurring, though I am
>>> seeing them both on the AS5400 and on the Customer router. They are
>>> performing a more indepth test now.
>>>
>>>
>>> _______________________________________________
>>> cisco-nas mailing list
>>> cisco-nas at puck.nether.net
>>> https://puck.nether.net/mailman/listinfo/cisco-nas
>>
>> _______________________________________________
>> cisco-nas mailing list
>> cisco-nas at puck.nether.net
>> https://puck.nether.net/mailman/listinfo/cisco-nas
>>
> _______________________________________________
> cisco-nas mailing list
> cisco-nas at puck.nether.net
> https://puck.nether.net/mailman/listinfo/cisco-nas
--------------------------------------------------------------
_______________________________________________
cisco-nas mailing list
cisco-nas at puck.nether.net
https://puck.nether.net/mailman/listinfo/cisco-nas
------------------------------------------------------------------
_______________________________________________
cisco-nas mailing list
cisco-nas at puck.nether.net
https://puck.nether.net/mailman/listinfo/cisco-nas
_______________________________________________
cisco-nas mailing list
cisco-nas at puck.nether.net
https://puck.nether.net/mailman/listinfo/cisco-nas
----------------------------------------------------------------------
_______________________________________________
cisco-nas mailing list
cisco-nas at puck.nether.net
https://puck.nether.net/mailman/listinfo/cisco-nas
------------------------------------------------------------------------------
_______________________________________________
cisco-nas mailing list
cisco-nas at puck.nether.net
https://puck.nether.net/mailman/listinfo/cisco-nas
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://puck.nether.net/pipermail/cisco-nas/attachments/20121011/86b86ded/attachment-0001.html>
More information about the cisco-nas
mailing list