How to Debug Trunk Interfaces - Revision history

Luc Morissette: Added T1/E1 errors

2020-11-12T21:05:19Z

Added T1/E1 errors

Nicole Tan: NT: Added note about the Cable Type for ISDN User or Network

2020-06-30T18:39:39Z

NT: Added note about the Cable Type for ISDN User or Network

Luc Morissette at 07:29, 15 June 2011

2011-06-15T07:29:03Z

Luc Morissette at 07:25, 15 June 2011

2011-06-15T07:25:19Z

Luc Morissette at 13:11, 11 May 2011

2011-05-11T13:11:44Z

Lucas Trottier at 19:56, 8 December 2010

2010-12-08T19:56:23Z

Luc Morissette: RFC -> RFC2495

2010-03-05T14:49:14Z

RFC -> RFC2495

Luc Morissette: Added "How to Debug Trunk Interfaces"

2010-02-10T21:07:26Z

Added "How to Debug Trunk Interfaces"

New page

Connecting a trunk interface should be easy - right? Well it is more complicated than it seems because many conditions have some effect on the final installation.

Here are some examples: 

#Cables 
#Port used on Tmedia units 
#Port used on remote device 
#Framing 
#Line encoding 

In general, cabling makes all the difference when connecting a trunk interface. In most cases, after the local and remote trunk Ports are carefully selected and default configuration is used, cabling is the last thing that can cause a problem. 

To check the status of the trunk on the web portal go here: 

Status -> TDM lines -> click on the trunk -> Click on extended status -> Refresh now 

Most of these parameters are defined in RFC2495 ([http://www.faqs.org/rfcs/rfc2495.html www.faqs.org/rfcs/rfc2495.html]), but here is a guideline for different errors encountered:

1. If you have LOS (Loss of Signal) -> Check cabling 

2. If you have LOF/OOF (Loss of Frame) -> Check framing and type of trunk (E1 vs T1) 

3. If you have RAI/RRA (Remote Alarm Indication) -> Check cabling 

4. If you have RSP/RSN (Receive Slip) -> Clocking is not set correctly 

5. Other errors, like FEC (Forward Error Correction)  and CVC (Code violations) are usually not critical, but should be verified -> Check cabling

 

You can also reset the status to get fresh information: 

Click on Reset status -> Refresh now -> Unclick on Reset status  -> Refresh now (again) 

 

'''Possibles causes of bad cabling:''' 

1. Straight vs Crossover 

Depending on the installation, the cable required can be a straight one or a crossover. Make sure the right one is used in the installation. This is detected with a LOS signal on the line. 

*Straight E1 cable (same for T1 and J1): pairs 1-2 and 4-5 must be the twisted pairs. This is different than a ethernet cable. It does not affect the system over short distances. 
*Crossover E1 cable: pairs 1-2 and 4-5 must be crossed. 

2. Only half way is working

This is easy to detect as the RAI/RRA alarm will be set on one end (1) and LOS on the other end (2). This means the path from (1) to (2) is down and path from (2) to (1) is up.

3. Quality of the cable 

If the cable is not perfect, it may causes various errors like Code Violations. In general this will not affect the status of the line, but will generate static on the line and may prevent data communication, like HDLC processing for ISDN and SS7. Reference to other status parameters can be found in RFC

3. 75 ohms E1 connections 

E1 75 ohms/120 ohms conversion requires an external Balun module 

 

'''Default parameters:''' 

E1 

*Line encoding is HDB3 
*Framing is AUTO, which supports both MFRAME (multiframe, or with CRC) and STD (doubleframe without CRC) 
*Line length is SHORT 

T1/J1 

*Line encoding is B8ZS 
*Framing is ESF (extended Super Frame)
*Line length is SHORT

 

Note: Trunk ports on Tmedia 16 E1 and Tmedia 64E1 with patch panels are not in the same order of connection. Please verify in the respective installation guides.

@@ Line 81: / Line 81: @@
 Note: Trunk ports on Tmedia 16 E1 and Tmedia 64E1 with patch panels are not in the same order of connection. Please verify in the respective installation guides.<br>
 == References  ==
 [http://www.cisco.com/en/US/tech/tk713/tk628/technologies_tech_note09186a00801069ff.shtml T1 Alarm Troubleshooting]

@@ Line 47: / Line 47: @@
 *Straight E1 cable (same for T1 and J1):&nbsp;pairs 1-2 and 4-5 must be the twisted pairs. This is different than a ethernet cable. It does not affect the system over short distances.<br>
 *Crossover E1 cable:&nbsp;pairs 1-2 and 4-5 must be crossed.<br>
 . Only half way is working

@@ Line 15: / Line 15: @@
 On the web portal&nbsp;: <br>
 <pre>Status -&gt; TDM lines -&gt; click on the trunk -&gt; Click on extended status -&gt; Refresh now
 </pre>
 Most of these parameters are defined in RFC2495 ([http://www.faqs.org/rfcs/rfc2495.html www.faqs.org/rfcs/rfc2495.html]), but here is a guideline for different errors encountered:
@@ Line 32: / Line 32: @@
 You can also reset the status to get fresh information:<br>
 <pre>Click on Reset status -&gt; Refresh now -&gt; Unclick on Reset status  -&gt; Refresh now (again)
 </pre>
 <br>
-You can also test with Trunk Loopbacks. Here is the procedure [[Parameter:_Loopback|how to use Loopback]].
+You can also test with Trunk Loopbacks. Here is the procedure [[Parameter: Loopback|how to use Loopback]].
-−
 '''Possibles causes of bad cabling:'''<br>
@@ Line 78: / Line 78: @@
 <br>
 Note: Trunk ports on Tmedia 16 E1 and Tmedia 64E1 with patch panels are not in the same order of connection. Please verify in the respective installation guides.<br>
 == References  ==
-[http://www.cisco.com/en/US/tech/tk713/tk628/technologies_tech_note09186a00801069ff.shtml| T1 Alarm Troubleshooting]

← Older revision		Revision as of 07:25, 15 June 2011
Line 79:		Line 79:

	Note: Trunk ports on Tmedia 16 E1 and Tmedia 64E1 with patch panels are not in the same order of connection. Please verify in the respective installation guides.<br>		Note: Trunk ports on Tmedia 16 E1 and Tmedia 64E1 with patch panels are not in the same order of connection. Please verify in the respective installation guides.<br>
		+
		+	== References ==
		+	[http://www.cisco.com/en/US/tech/tk713/tk628/technologies_tech_note09186a00801069ff.shtml\| T1 Alarm Troubleshooting]

@@ Line 1: / Line 1: @@
 Connecting a trunk interface should be easy - right? Well it is more complicated than it seems because many conditions have some effect on the final installation.
 Here are some examples:<br>
 #Cables<br>
 #Port used on Tmedia units<br>
 #Port used on remote device<br>
 #Framing<br>
 #Line encoding<br>
 In general, cabling makes all the difference when connecting a trunk interface. In most cases, after the local and remote trunk Ports are carefully selected and default configuration is used, cabling is the last thing that can cause a problem.<br>
-To check the status of the trunk : [[Toolpack v2.5:Status Menus:TDM Lines]]
+To check the status of the trunk&nbsp;: [[Toolpack v2.5:Status Menus:TDM Lines]]
-On the web portal : <br>
+On the web portal&nbsp;: <br>
-Status -&gt; TDM lines -&gt;&nbsp;click on the trunk -&gt;&nbsp;Click on extended status -&gt;&nbsp;Refresh now<br>
+. If you have LOS (Loss of Signal) -&gt; Check cabling<br>
-Most of these parameters are defined in RFC2495 ([http://www.faqs.org/rfcs/rfc2495.html www.faqs.org/rfcs/rfc2495.html]), but here is a guideline for different errors encountered:
+. If you have LOF/OOF (Loss of Frame) -&gt; Check framing and type of trunk (E1 vs T1)<br>
-. If you have LOS (Loss of Signal) -&gt; Check cabling<br>
+. If you have RAI/RRA (Remote Alarm Indication) -&gt; Check cabling<br>
-. If you have LOF/OOF (Loss of Frame) -&gt; Check framing and type of trunk (E1 vs T1)<br>
+. If you have RSP/RSN (Receive Slip)&nbsp;-&gt; Clocking is not set correctly<br>
-. If you have RAI/RRA (Remote Alarm Indication) -&gt; Check cabling<br>
+. Other errors, like FEC (Forward Error Correction)&nbsp; and CVC (Code violations) are usually not critical, but should be verified -&gt; Check cabling
-. If you have RSP/RSN (Receive Slip)&nbsp;-&gt; Clocking is not set correctly<br>
+<br>
-. Other errors, like FEC (Forward Error Correction)&nbsp; and CVC (Code violations) are usually not critical, but should be verified -&gt; Check cabling
+You can also reset the status to get fresh information:<br>
-<br>
+You can also test with Trunk Loopbacks. Here is the procedure [[Parameter:_Loopback|how to use Loopback]].
-<br>
+'''Possibles causes of bad cabling:'''<br>
-'''Possibles causes of bad cabling:'''<br>
+. Straight vs Crossover<br>
-. Straight vs Crossover<br>
+Depending on the installation, the cable required can be a straight one or a crossover. Make sure the right one is used in the installation. This is detected with a LOS signal on the line.<br>
-Depending on the installation, the cable required can be a straight one or a crossover. Make sure the right one is used in the installation. This is detected with a LOS signal on the line.<br>
+*Straight E1 cable (same for T1 and J1):&nbsp;pairs 1-2 and 4-5 must be the twisted pairs. This is different than a ethernet cable. It does not affect the system over short distances.<br>
-−
 *Straight E1 cable (same for T1 and J1):&nbsp;pairs 1-2 and 4-5 must be the twisted pairs. This is different than a ethernet cable. It does not affect the system over short distances.<br>
 *Crossover E1 cable:&nbsp;pairs 1-2 and 4-5 must be crossed.<br>
 . Only half way is working
 This is easy to detect as the RAI/RRA alarm will be set on one end (1) and LOS on the other end (2). This means the path from (1)&nbsp;to (2) is down and path from (2) to (1) is up.
 . Quality of the cable<br>
 If the cable is not perfect, it may causes various errors like Code Violations. In general this will not affect the status of the line, but will generate static on the line and may prevent data communication, like HDLC processing for ISDN and SS7. Reference to other status parameters can be found in RFC 2495
 . 75 ohms E1 connections<br>
 E1 75 ohms/120 ohms conversion requires an external Balun module<br>
 <br>
 '''Default parameters:'''<br>
 E1<br>
 *Line encoding is HDB3<br>
 *Framing is AUTO, which supports both MFRAME (multiframe, or with CRC) and STD (doubleframe without CRC)<br>
 *Line length is SHORT<br>
 T1/J1<br>
 *Line encoding is B8ZS<br>
 *Framing is ESF (extended Super Frame)
 *Line length is SHORT
 <br>
 Note: Trunk ports on Tmedia 16 E1 and Tmedia 64E1 with patch panels are not in the same order of connection. Please verify in the respective installation guides.<br>