sniderman42
asked on
cannot run successful BERT on cisco router with loopback plug on good T1 port
I'm trying to run BERT on a Cisco on a line that I know is good (so I expect good BERT result). But even with a T1 loopback plug (shorted pins 1to4, 2to5) directly in the Cisco T1 port, I get 0 syncs (port shows carrier detect). The equipment at the other end of the line seemed to successfully receive the loopback command and place itself into loopback mode.
I am new to BERT, so I am not confident that I've set everything up properly. I am confident that I am using the correct port (I have 4 T1s in an MLFR configuration, which works well). I started by changing encapsulation of the serial interface 0/1:0 to hdlc, and sending remote loopback command from controller 0/1 (I have two dual T1 controllers - VWIC-2MFT-T1).
Here are my results running the test with a loopback plug:
Router7008#bert controller t1 0/1 channel-group 0 pattern qrss interval 1
Router7008#show controller t1 0/1 bert
T1 0/1 is up. (Far End Line Loopback with ESF BOC)
BERT is in progress on channel-group 0. The result of last time is
DSX1 BERT status : no sync
DSX1 BERT pattern : QRSS
DSX1 BERT sync count : 0
DSX1 BERT interval : 1 min
DSX1 BERT time remain : 0 min 48 sec
DSX1 BERT total errs : 1415275113
DSX1 BERT total k bits: 921553
DSX1 BERT errors (last): 0
DSX1 BERT k bits (last): 0
Router7008#show controller t1 0/1 bert
T1 0/1 is up. (Far End Line Loopback with ESF BOC)
BERT is in progress on channel-group 0. The result of last time is
DSX1 BERT status : no sync
DSX1 BERT pattern : QRSS
DSX1 BERT sync count : 0
DSX1 BERT interval : 1 min
DSX1 BERT time remain : 0 min 34 sec
DSX1 BERT total errs : 557404520
DSX1 BERT total k bits: 3159612
DSX1 BERT errors (last): 0
DSX1 BERT k bits (last): 0
Router7008#show controller t1 0/1 bert
T1 0/1 is up. (Far End Line Loopback with ESF BOC)
BERT is done on channel-group 0. The result of last time is
DSX1 BERT status : done
DSX1 BERT pattern : QRSS
DSX1 BERT sync count : 0
DSX1 BERT interval : 1 min
DSX1 BERT time remain : 0 min 0 sec
DSX1 BERT total errs : 4147541425
DSX1 BERT total k bits: 8293982
DSX1 BERT errors (last): 0
DSX1 BERT k bits (last): 0
Router7008#
and here is my running-config:
Current configuration : 3136 bytes
!
! Last configuration change at 16:23:32 PST Thu Jan 28 2010
!
version 12.3
service timestamps debug datetime msec
service timestamps log datetime msec localtime
no service password-encryption
!
hostname Router7008
!
boot-start-marker
boot-end-marker
!
!
clock timezone PST -8
no network-clock-participate slot 1
no network-clock-participate wic 0
no aaa new-model
ip subnet-zero
ip cef
!
!
ip dhcp excluded-address 10.10.45.1 10.10.45.150
ip dhcp excluded-address 10.10.46.1 10.10.46.150
!
ip dhcp pool T1
network 10.10.45.0 255.255.255.0
default-router 10.10.45.1
dns-server 12.127.17.72 12.127.16.68
!
ip dhcp pool T1_2
network 10.10.46.0 255.255.255.0
default-router 10.10.46.1
dns-server 12.127.17.72 12.127.16.68
!
ip audit po max-events 100
multilink bundle-name both
frame-relay switching
!
!
!
!
!
!
!
!
!
!
!
!
!
!
controller T1 0/0
framing esf
fdl both
clock source internal
linecode b8zs
cablelength short 133
channel-group 0 timeslots 1-24 speed 64
!
controller T1 0/1
framing esf
fdl both
clock source internal
linecode b8zs
cablelength short 133
channel-group 0 timeslots 1-24 speed 64
loopback remote esf line
!
controller T1 0/2
framing esf
fdl both
clock source internal
linecode b8zs
cablelength short 133
channel-group 0 timeslots 1-24 speed 64
!
controller T1 0/3
framing esf
fdl both
clock source internal
linecode b8zs
cablelength short 133
channel-group 0 timeslots 1-24 speed 64
!
!
!
!
!
interface MFR0
mtu 9172
no ip address
encapsulation frame-relay IETF
frame-relay multilink output-threshold 512
frame-relay lmi-type ansi
frame-relay intf-type dce
!
interface MFR0.16 point-to-point
ip address 10.10.45.1 255.255.255.0
no cdp enable
frame-relay interface-dlci 16
!
interface FastEthernet0/0
ip address 10.10.30.103 255.255.255.0
duplex auto
speed auto
no cdp enable
!
interface Serial0/0:0
mtu 9180
no ip address
encapsulation frame-relay MFR0
load-interval 30
no arp frame-relay
!
interface FastEthernet0/1
ip address 192.168.1.1 255.255.255.0
shutdown
duplex auto
speed auto
no cdp enable
!
interface Serial0/1:0
mtu 9180
no ip address
load-interval 30
!
interface Serial0/2:0
mtu 9180
no ip address
encapsulation frame-relay MFR0
load-interval 30
no arp frame-relay
!
interface Serial0/3:0
mtu 9180
no ip address
encapsulation frame-relay MFR0
load-interval 30
no arp frame-relay
!
interface Virtual-Template45
ip address 10.10.45.10 255.255.255.0
peer default ip address dhcp-pool T1
ppp authentication chap pap
ppp multilink
!
interface Virtual-Template46
ip address 10.10.46.10 255.255.255.0
peer default ip address dhcp-pool T1_2
ppp authentication chap pap
ppp multilink
!
ip http server
no ip http secure-server
ip classless
ip route 0.0.0.0 0.0.0.0 10.10.30.1
ip route 10.1.1.0 255.255.255.0 10.10.45.100
ip route 10.10.30.0 255.255.255.0 FastEthernet0/0
!
!
access-list 100 deny icmp any any echo
!
!
!
!
!
!
line con 0
line aux 0
line vty 0 4
login
!
ntp clock-period 17179716
ntp server 192.43.244.18
!
end
I am new to BERT, so I am not confident that I've set everything up properly. I am confident that I am using the correct port (I have 4 T1s in an MLFR configuration, which works well). I started by changing encapsulation of the serial interface 0/1:0 to hdlc, and sending remote loopback command from controller 0/1 (I have two dual T1 controllers - VWIC-2MFT-T1).
Here are my results running the test with a loopback plug:
Router7008#bert controller t1 0/1 channel-group 0 pattern qrss interval 1
Router7008#show controller t1 0/1 bert
T1 0/1 is up. (Far End Line Loopback with ESF BOC)
BERT is in progress on channel-group 0. The result of last time is
DSX1 BERT status : no sync
DSX1 BERT pattern : QRSS
DSX1 BERT sync count : 0
DSX1 BERT interval : 1 min
DSX1 BERT time remain : 0 min 48 sec
DSX1 BERT total errs : 1415275113
DSX1 BERT total k bits: 921553
DSX1 BERT errors (last): 0
DSX1 BERT k bits (last): 0
Router7008#show controller t1 0/1 bert
T1 0/1 is up. (Far End Line Loopback with ESF BOC)
BERT is in progress on channel-group 0. The result of last time is
DSX1 BERT status : no sync
DSX1 BERT pattern : QRSS
DSX1 BERT sync count : 0
DSX1 BERT interval : 1 min
DSX1 BERT time remain : 0 min 34 sec
DSX1 BERT total errs : 557404520
DSX1 BERT total k bits: 3159612
DSX1 BERT errors (last): 0
DSX1 BERT k bits (last): 0
Router7008#show controller t1 0/1 bert
T1 0/1 is up. (Far End Line Loopback with ESF BOC)
BERT is done on channel-group 0. The result of last time is
DSX1 BERT status : done
DSX1 BERT pattern : QRSS
DSX1 BERT sync count : 0
DSX1 BERT interval : 1 min
DSX1 BERT time remain : 0 min 0 sec
DSX1 BERT total errs : 4147541425
DSX1 BERT total k bits: 8293982
DSX1 BERT errors (last): 0
DSX1 BERT k bits (last): 0
Router7008#
and here is my running-config:
Current configuration : 3136 bytes
!
! Last configuration change at 16:23:32 PST Thu Jan 28 2010
!
version 12.3
service timestamps debug datetime msec
service timestamps log datetime msec localtime
no service password-encryption
!
hostname Router7008
!
boot-start-marker
boot-end-marker
!
!
clock timezone PST -8
no network-clock-participate slot 1
no network-clock-participate wic 0
no aaa new-model
ip subnet-zero
ip cef
!
!
ip dhcp excluded-address 10.10.45.1 10.10.45.150
ip dhcp excluded-address 10.10.46.1 10.10.46.150
!
ip dhcp pool T1
network 10.10.45.0 255.255.255.0
default-router 10.10.45.1
dns-server 12.127.17.72 12.127.16.68
!
ip dhcp pool T1_2
network 10.10.46.0 255.255.255.0
default-router 10.10.46.1
dns-server 12.127.17.72 12.127.16.68
!
ip audit po max-events 100
multilink bundle-name both
frame-relay switching
!
!
!
!
!
!
!
!
!
!
!
!
!
!
controller T1 0/0
framing esf
fdl both
clock source internal
linecode b8zs
cablelength short 133
channel-group 0 timeslots 1-24 speed 64
!
controller T1 0/1
framing esf
fdl both
clock source internal
linecode b8zs
cablelength short 133
channel-group 0 timeslots 1-24 speed 64
loopback remote esf line
!
controller T1 0/2
framing esf
fdl both
clock source internal
linecode b8zs
cablelength short 133
channel-group 0 timeslots 1-24 speed 64
!
controller T1 0/3
framing esf
fdl both
clock source internal
linecode b8zs
cablelength short 133
channel-group 0 timeslots 1-24 speed 64
!
!
!
!
!
interface MFR0
mtu 9172
no ip address
encapsulation frame-relay IETF
frame-relay multilink output-threshold 512
frame-relay lmi-type ansi
frame-relay intf-type dce
!
interface MFR0.16 point-to-point
ip address 10.10.45.1 255.255.255.0
no cdp enable
frame-relay interface-dlci 16
!
interface FastEthernet0/0
ip address 10.10.30.103 255.255.255.0
duplex auto
speed auto
no cdp enable
!
interface Serial0/0:0
mtu 9180
no ip address
encapsulation frame-relay MFR0
load-interval 30
no arp frame-relay
!
interface FastEthernet0/1
ip address 192.168.1.1 255.255.255.0
shutdown
duplex auto
speed auto
no cdp enable
!
interface Serial0/1:0
mtu 9180
no ip address
load-interval 30
!
interface Serial0/2:0
mtu 9180
no ip address
encapsulation frame-relay MFR0
load-interval 30
no arp frame-relay
!
interface Serial0/3:0
mtu 9180
no ip address
encapsulation frame-relay MFR0
load-interval 30
no arp frame-relay
!
interface Virtual-Template45
ip address 10.10.45.10 255.255.255.0
peer default ip address dhcp-pool T1
ppp authentication chap pap
ppp multilink
!
interface Virtual-Template46
ip address 10.10.46.10 255.255.255.0
peer default ip address dhcp-pool T1_2
ppp authentication chap pap
ppp multilink
!
ip http server
no ip http secure-server
ip classless
ip route 0.0.0.0 0.0.0.0 10.10.30.1
ip route 10.1.1.0 255.255.255.0 10.10.45.100
ip route 10.10.30.0 255.255.255.0 FastEthernet0/0
!
!
access-list 100 deny icmp any any echo
!
!
!
!
!
!
line con 0
line aux 0
line vty 0 4
login
!
ntp clock-period 17179716
ntp server 192.43.244.18
!
end
ASKER
no provider - I control both ends of the T1; The cisco is configured as the provider, with a T1 loopback plug in the 0/1 T1 port.
what type of dce device do you use?
ASKER
The only equipment in the test is a Cisco2621XM router with a loopback plug in the T1 (0/1) port; the BERT test is being run from the Cisco. As far as I understand BERT, this should be enough to run a loopback test successfully (the T1 port being used is a known-good port for T1).
interesting, plesae plug loop the remote end and tell us
ASKER
The results listed in the description are from a bert test with loopback in remote end. Test fails.
Hello
If you are testing with a hard loopback plug, you should remove the command loopback remote esf line under your controller T1 0/1 configuration and then start again the bert test.
You do not need to have your controller configure in loopback mode if you are already using a Hard Plug Loopback.
hope it helps
If you are testing with a hard loopback plug, you should remove the command loopback remote esf line under your controller T1 0/1 configuration and then start again the bert test.
You do not need to have your controller configure in loopback mode if you are already using a Hard Plug Loopback.
hope it helps
ASKER
Hard loopback plug test still fails with loopback command removed from under controller T1 0/1.
ASKER
I have also tried same thing on a newer router (also with loopback plug) so it doesn't appear to be a hardware problem.
ASKER CERTIFIED SOLUTION
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ASKER
fwiw - also found that successful bert test followed the card to other routers
If 1-24 please ask a loop from ISP node to nodes to find which node causes BERT