ISDN PRI on Cisco AS5300 problems

nsa.usa@gmail.com · Guest

Hi,

I've got a Layer 2 problem. I have a 'Fractional' E1 (15 lines) that I
need to configure for dial-in to a cisco AS5300.
My telco is very useless as I am in Mozambique. They can't even tell me
the switch-type, but can only say it is 'the european type'. So I
assume it's 'primary-net5'.
Anyway, I got 'Layer 1' ACTIVE....hooray.
Layer 2 says either TEI_ASSIGNED or AWAITING ESTABLISHEMENT.

A debug isdn q921 gives me this (I know, the date is wrong):
**Jan 8 04:08:03.321: ISDN Se0:15 Q921: User TX -> SABMEp sapi=0 tei=0
*Jan 8 04:08:04.321: ISDN Se0:15 Q921: User TX -> SABMEp sapi=0 tei=0
*Jan 8 04:08:10.321: ISDN Se0:15 Q921: User TX -> SABMEp sapi=0 tei=0
*Jan 8 04:08:11.321: ISDN Se0:15 Q921: User TX -> SABMEp sapi=0 tei=0
*Jan 8 04:08:12.321: ISDN Se0:15 Q921: User TX -> SABMEp sapi=0 tei=0

etc.

This is the *only* packet (well, many of this one) that is ever
transmitted (nothing is ever received). I read somewhere that the
router should request a TEI from the telco switch but it doesnt seem
to. How can I get it to do that? doing shutdown/no shutdown on the
interface/controller doesnt help or 'clear interface serial0:15'
doesn't help either.
The telco says they can see the q921 packets and their switch is saying
my router has some problem or something. Somewhere else it said to
issue 'isdn tei-negotiation first-call' but I don't seem to have this
command available.
Now they just told me they use 'signalling number 7' whatever that
means. Should I tell my cisco router this? how?

Please find below various outputs.
Any help is much appreciated. Thanks alot! (sorry about the length of
this message, but I think outputs are necessary.)

Tobias

****************************************
#show controller e1 0
****************************************
E1 0 is up.
Applique type is Channelized E1 - balanced
No alarms detected.
alarm-trigger is not set
Version info of slot 0: HW: 1, PLD Rev: 11
Framer Version: 0x8

Manufacture Cookie Info:
EEPROM Type 0x0001, EEPROM Version 0x01, Board ID 0x49,
Board Hardware Version 2.0, Item Number 800-3883-02,
Board Revision A0, Serial Number 17425312,
PLD/ISP Version 0.1, Manufacture Date 18-Jan-2000.

Framing is CRC4, Line Code is HDB3, Clock Source is Line Primary.
Data in current interval (90 seconds elapsed):
0 Line Code Violations, 0 Path Code Violations
0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins
0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail
Secs
Data in Interval 1:
0 Line Code Violations, 0 Path Code Violations
0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins
0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail
Secs
Data in Interval 2:
0 Line Code Violations, 0 Path Code Violations
0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins
0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail
Secs
Data in Interval 3:
0 Line Code Violations, 0 Path Code Violations
0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins
0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail
Secs
Total Data (last 3 15 minute intervals):
0 Line Code Violations, 0 Path Code Violations,
0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins,
0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail
Secs

****************************************
#show interface serial0:15
****************************************
Serial0:15 is up, line protocol is up (spoofing)
Hardware is DSX1
MTU 1500 bytes, BW 64 Kbit, DLY 20000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation PPP, loopback not set
Keepalive set (10 sec)
Last input never, output never, output hang never
Last clearing of "show interface" counters 00:49:56
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: weighted fair
Output queue: 0/1000/64/0 (size/max total/threshold/drops)
Conversations 0/1/256 (active/max active/max total)
Reserved Conversations 0/0 (allocated/max allocated)
Available Bandwidth 48 kilobits/sec
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
1332 packets output, 3996 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 output buffer failures, 0 output buffers swapped out
0 carrier transitions
Timeslot(s) Used:16, Transmitter delay is 0 flags

****************************************
#show isdn status
****************************************
Global ISDN Switchtype = primary-net5
ISDN Serial0:15 interface
dsl 0, interface ISDN Switchtype = primary-net5
Layer 1 Status:
ACTIVE
Layer 2 Status:
TEI = 0, Ces = 1, SAPI = 0, State = AWAITING_ESTABLISHMENT
Layer 3 Status:
0 Active Layer 3 Call(s)
Active dsl 0 CCBs = 0
The Free Channel Mask: 0x00007FFF
Number of L2 Discards = 0, L2 Session ID = 85

****************************************
#show running-config
****************************************
!
resource-pool disable
!
no aaa new-model
ip subnet-zero
ip name-server aaa.bbb.ccc.ddd (sanitized)
!
async-bootp dns-server 192.168.10.1 192.168.10.2
!
isdn switch-type primary-net5
!
!
controller E1 0
clock source line primary
pri-group timeslots 1-16
!
controller E1 1
clock source line secondary 1
!
controller E1 2
clock source line secondary 2
!
controller E1 3
clock source line secondary 3
!
controller E1 4
!
controller E1 5
!
controller E1 6
!
controller E1 7
!
!
interface Loopback0
ip address 192.168.12.1 255.255.255.0
!
interface Ethernet0
ip address ***sanitized*** 255.255.255.240
shutdown
!
interface Serial0
no ip address
shutdown
clockrate 2015232
no fair-queue
!
interface Serial1
no ip address
shutdown
clockrate 2015232
no fair-queue
!
interface Serial2
no ip address
shutdown
clockrate 2015232
no fair-queue
!
interface Serial3
no ip address
shutdown
clockrate 2015232
no fair-queue
!
interface Serial0:15
no ip address
encapsulation ppp
isdn switch-type primary-net5
isdn incoming-voice modem
!
interface FastEthernet0
ip address 192.168.11.1 255.255.255.0 secondary
ip address 192.168.23.2 255.255.255.0 secondary
ip address 10.5.0.1 255.255.224.0 secondary
ip address ***sanitized*** 255.255.255.240
duplex auto
speed auto
!
interface Group-Async1
ip unnumbered Loopback0
encapsulation ppp
async mode interactive
peer default ip address pool dialin_pool
ppp authentication chap pap
group-range 1 240
!
ip local pool dialin-pool 192.168.12.2 192.168.12.242
ip default-gateway ***sanitized ***
ip classless
ip route 0.0.0.0 0.0.0.0 FastEthernet0 ***sanitized***
ip route 10.5.0.0 255.255.224.0 FastEthernet0 10.5.0.10
ip route 10.5.4.0 255.255.252.0 FastEthernet0 10.5.0.10
ip route 10.5.8.0 255.255.252.0 FastEthernet0 10.5.0.10
ip route 10.5.12.0 255.255.252.0 FastEthernet0 10.5.0.10
ip route 10.5.16.0 255.255.252.0 FastEthernet0 10.5.0.10
ip route 10.5.20.0 255.255.252.0 FastEthernet0 10.5.0.10
ip route 10.5.24.0 255.255.252.0 FastEthernet0 10.5.0.10
ip route 10.5.28.0 255.255.252.0 FastEthernet0 10.5.0.10
ip route 192.168.10.0 255.255.255.0 FastEthernet0 192.168.23.1
no ip http server
!
line con 0
password ***sanitized***
line 1 240
modem InOut
autoselect during-login
autoselect ppp
line aux 0
autoselect during-login
autoselect ppp
line vty 0 4
password ***sanitized***
login
autoselect during-login
autoselect ppp
!
end

Merv · Guest

The outputs are excellent and necessary.

see "E1 PRI Troubleshooting" regarding SABME messages

http://www.cisco.com/en/US/tech/tk713/tk628/technologies_tech_note09186a00800f9e3a.shtml

"Verify that asynchronous balanced mode extended (SABME) messages do
not appear. These messages indicate that Layer 2 is trying to
reinitialize. The messages usually appear when poll requests (RRp) are
transmitted and there is no response from the switch (RRf), or vice
versa. Following are examples of SABME messages:

Mar 20 10:06:21.702: ISDN Se0:15: RX <- SABMEp sapi = 0 tei = 0
Mar 20 10:06:22.494: ISDN Se0:15: TX -> SABMEp sapi = 0 tei = 0
"

try "isdn switch-type primary-ni" and shut/noshut interface

Vladimir Bilik · Guest

Hi,
your configuration seems to be OK.
try to make a call to number assigned to PRA. After this you
should get the status of Layer 2 "MULTIPLE_FRAME_ESTABLISHED"

Check if the TS 16 on the PRA is connected as well as the voice channels.

Regards,
Vladimir

nsa.usa@gmail.com wrote:

nsa.usa@gmail.com · Guest

Hi,
Thanks for quick reply.
I checked the link but had allready seen it before.
I also tried the other switch-type but there is no change.
I'm getting lots of the SABME messages (like 1 every sec), i.e.:
Mar 20 10:06:22.494: ISDN Se0:15: TX -> SABMEp sapi = 0 tei = 0

But only in the TX direction(!) there seems to be no response from the
telco-switch.
Could the wiring be wrong? If so would Layer 1 not be down? I'm
connected with a standard cat.5 network patch-cable (straight thru).
The telco-box has coax-sockets with a 120-ohm adapter to the cat.5.
It's correct to use the patch-cable right?

I'm giving up for today, maybe sleeping on it can help :-)

Regards,
Tobias

nsa.usa@gmail.com · Guest

Hi,

When I call the number, I get a busy signal....
My telco says everything is fine at their side but somehow I don't
think they know what they're doing (and neither do I =:-) )

Thanks.
Regards,
Tobias

Merv · Guest

also try configuring for a full E1 in case the D channel is not on
channel 16

Merv · Guest

forget last as I realized that D channel is always on channel 16 for E1.

Aaron Leonard · Guest

~ I've got a Layer 2 problem. I have a 'Fractional' E1 (15 lines) that I
~ need to configure for dial-in to a cisco AS5300.
~ My telco is very useless as I am in Mozambique. They can't even tell me
~ the switch-type, but can only say it is 'the european type'. So I
~ assume it's 'primary-net5'.
~ Anyway, I got 'Layer 1' ACTIVE....hooray.
~ Layer 2 says either TEI_ASSIGNED or AWAITING ESTABLISHEMENT.
~
~ A debug isdn q921 gives me this (I know, the date is wrong):
~ **Jan 8 04:08:03.321: ISDN Se0:15 Q921: User TX -> SABMEp sapi=0 tei=0

~ This is the *only* packet (well, many of this one) that is ever
~ transmitted (nothing is ever received).

So we are sending Q.921 packets to the switch, on timeslot 15, but the
switch is not responding.

~ I read somewhere that the
~ router should request a TEI from the telco switch but it doesnt seem
~ to.

That's a BRI thing.

~ The telco says they can see the q921 packets and their switch is saying
~ my router has some problem or something.

What do they mean, they can "see" the Q.921 packets. Do they see them
AS Q.921 packets, meaning that our D channel is talking to their D channel?
Or do they see them as some unknown data activity appearing on some random
channel?

Can you find out specifically what the switch is "saying" about how the
router "has some problem or something"? An error message perhaps?

~ Somewhere else it said to
~ issue 'isdn tei-negotiation first-call' but I don't seem to have this
~ command available.

BRI thing.

~ Now they just told me they use 'signalling number 7' whatever that
~ means. Should I tell my cisco router this? how?

Are they saying that they do NOT want to talk ISDN PRI to you, but instead
want to talk SS7 to you?? For a mere 15 trunks?? I am skeptical of that.
SS7 is a signaling protocol that is entirely different from ISDN, and that
uses a separate physical path (a "DS0A") for the call signaling. The AS5300
cannot talk SS7 natively, but would need to use a signaling gateway.

I am inclined to agree with your hypothesis that your contacts at the telco
don't know what they're talking about. Perhaps this 1/2 E1 is actually set up
for R2 signaling rather than for ISDN? Try using the term "R2" and seeing if
it rings a bell with your contacts.

Good luck,

Aaron

Merv · Guest