Issue Description
Basically we want to connect our Huawei router with the Cisco Router over the E1 cable. The Cisco persons want to use the Framed E1 for this purpose. On our Router the default configuration was the unframed E1. This document explain the steps how I configured the framed E1. We are using the “AR 28-31” router with “VRP(R) software, Version 3.40, Release RT-0009”.
Network Diagram :--
The Networking diagram is contained in “Fig 1.rar”. The Networking was pretty straight forward. The E1 from the other end terminates at our serial interface “1/1:0”.
Type of Router :- AR 28-31
Alarm Information
[Quidway]dis int ser1/1:0
Serial1/1:0 current state :UP
Line protocol current state :DOWN
Description : Instaphone E1
The Maximum Transmit Unit is 1500, Hold timer is 10(sec)
Derived from E1 1/1, Unframed mode, baudrate is 2048000 bps
Internet Address is 172.20.250.17/30
Link layer protocol is PPP
The Line protocol was down bcz the other operator was using the framed mode while we were using the unframed mode.
Handling Process
For resolving this problem I undertook the following steps:
1) First of all I used the command “dis curr” and the state of the controller and the interface was like this
controller E1 1/1
using e1
#
interface Serial1/1:0
link-protocol ppp
ip address ppp-negotiate
#
2) Then I used the command “dis int ser1/1:0” and I found the following output
[Quidway]dis int ser1/1:0
Serial1/1:0 current state :UP
Line protocol current state :DOWN
Description : Instaphone E1
The Maximum Transmit Unit is 1500, Hold timer is 10(sec)
Derived from E1 1/1, Unframed mode, baudrate is 2048000 bps
Internet Address is 172.20.250.17/30
Link layer protocol is PPP
3) Since the Cisco side have configured to use the Framed mode I also want to make the same configuration on my side.
4) I go to the serial 1/1:0 and type the “?” to see whether there is some command for using the framed mode.
[Quidway-Serial1/1:0]?
Here I don’t find any command which could change our E1 to framing mode.
5) Then I go to the controller and used “?” I get following information
[Quidway-E1 1/1]?
E1 controller view commands:
cable Set cable type
clock Set E1 clock
code Set the linecode type of the physical link
enable Enable function
idlecode Set idle timeslots code
itfcode Set interframe filling code
loopback Set interface loopback
msdp-tracert MSDP traceroute to source RP
mtracert Trace route to multicast source
nslookup Query Internet name servers
ping Send echo messages
quit Exit from current command view
restart Restart the port
return Exit to User View
using Change the interface mode between CE1 and E1
Here I apprehend that I can make use of the “using” command
6) The controller was previously using the E1 mode which was basically the unframed mode. I used the command “using CE1” to switch to CE1 mode.
7) After switching to CE1 mode, I used the command “dis curr” and I was a bit surprised to know that the serial interface “ser1/1:0” was not shown in the output.
8) This made me a bit worried but I had no option but to stick with the “CE1 mode”. Then I used the command “?” at the controller E1/1 and I found some new commands
[Quidway-E1 1/1]?
E1 controller view commands:
cable Set cable type
cas Configure R2 signaling parameters
channel-set Bind channel timeslot-list
clock Set E1 clock
code Set the linecode type of the physical link
display Display current system information
enable Enable function
frame-format Set the framing type of the physical link
idlecode Set idle timeslots code
itfcode Set interframe filling code
timeslot-set Set ds0-group timeslot
The underlined commands were not present previously when I was using the E1 Mode.
9) I used the command “channel-set 0 timeslot-list 1-31”. Then I used the command “dis int ser1/1:0” and I find the following output
[Quidway-Serial1/1:0]dis int ser1/1:0
Serial1/1:0 current state :UP
Line protocol current state :DOWN
Description : Serial1/1:0 Interface
The Maximum Transmit Unit is 1500, Hold timer is 10(sec)
Derived from E1 1/1, Timeslot(s) Used: 1-31, baudrate is 1984000 bps
Internet Address is 172.20.250.17/30
Link layer protocol is PPP
and the output of “dis curr” is as following
controller E1 1/1
channel-set 0 timeslot-list 1-31
#
interface Serial1/1:0
link-protocol ppp
description Instaphone E1
ip address 172.20.250.17 255.255.255.252
#
Root Cause
I was trying to configure the framed E1 using the E1 mode for the controller but it was not successful. Basically for the configuration of framed E1 we have to use the CE1 mode for the contoller.
Suggestions
If we encounter some fishy problem we should remain consistent and keep on trying different things to figure out the solution.