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ISDN PRI on Cisco AS5300 problems

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
Reply to
nsa.usa
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The outputs are excellent and necessary.

see "E1 PRI Troubleshooting" regarding SABME messages

formatting link
"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 "

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

Reply to
Merv

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

snipped-for-privacy@gmail.com wrote:

Reply to
Vladimir Bilik

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

Reply to
nsa.usa

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

Reply to
nsa.usa

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

Reply to
Merv

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

Reply to
Merv

~ 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

Reply to
Aaron Leonard

For ISDN PRI TEI is always 0, so router will not request TEI from switch.

The first message the router should sent to initilialize layer 2 is SABME with SAPI = 0 and TEI = 0 which is exactly what is happening.

Switch should respond with a UA frame.

Once it has done that layer 2 status should transition to MULTI_FRAME_ESTABLISHED

Reply to
Merv

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