2901 ISR - Cellular 0/0/0 interface flapping continually

[mthomas]

                   I am configuring a 2901 ISR with an EHWIC 4G LTE Verizon module for the first time.  I've followed the configuration instructions but I'm having trouble with the interface changing state to down every 30 seconds or so.  The dialer idle-timout is set to defaults. I'm also using a Verizon private IP address allocated in an IP pool for our enterprise environment. Any help would be greatly appreciated.

See attached configuration output below:

*Dec 10 21:42:03.586: %LINK-3-UPDOWN: Interface Cellular0/0/0, changed state to up

*Dec 10 21:42:04.586: %LINEPROTO-5-UPDOWN: Line protocol on Interface Cellular0/0/0, changed state to up

*Dec 10 21:42:48.106: %LINK-5-CHANGED: Interface Cellular0/0/0, changed state to reset

*Dec 10 21:42:49.106: %LINEPROTO-5-UPDOWN: Line protocol on Interface Cellular0/0/0, changed state to down

*Dec 10 21:42:53.106: %LINK-3-UPDOWN: Interface Cellular0/0/0, changed state to down

*Dec 10 21:43:07.426: %LINK-3-UPDOWN: Interface Cellular0/0/0, changed state to up

*Dec 10 21:43:08.426: %LINEPROTO-5-UPDOWN: Line protocol on Interface Cellular0/0/0, changed state to up

*Dec 10 21:43:18.986: %LINK-5-CHANGED: Interface Cellular0/0/0, changed state to reset

*Dec 10 21:43:19.986: %LINEPROTO-5-UPDOWN: Line protocol on Interface Cellular0/0/0, changed state to down

*Dec 10 21:43:23.986: %LINK-3-UPDOWN: Interface Cellular0/0/0, changed state to down

*Dec 10 21:43:39.338: %LINK-3-UPDOWN: Interface Cellular0/0/0, changed state to up

*Dec 10 21:43:40.338: %LINEPROTO-5-UPDOWN: Line protocol on Interface Cellular0/0/0, changed state to up

chat-script lte "" "AT!CALL" TIMEOUT 60 "OK" 

!

controller Cellular 0/0

!

interface Cellular0/0/0

ip address negotiated

encapsulation slip

dialer in-band

dialer string lte

dialer-group 1

!

!

ip route 0.0.0.0 0.0.0.0 Cellular0/0/0

!

line 0/0/0

script dialer lte

no exec

rxspeed 100000000

txspeed 50000000

dialer-list 1 protocol ip permit
!

line 0/0/0
script dialer lte
no exec
rxspeed 100000000
txspeed 50000000

*****

Thanks in advance for any assistance

[Richard Burts]

I have experienced symptoms similar to what you describe when configuring a router to use a cellular interface. The issue was caused when the provider sees traffic with a source address that is different from the subnet of the address that they assigned for the cellular. Since you show us only the parts of the config very specifically related to the cellular interface I can not be sure if this is your problem or not. But my first guess is that Verizon is seeing traffic with a source address that they do not expect and are resetting the cellular. I would check the address translation (or configure address translation) as a first step in troubleshooting.

HTH

Rick

[bhavinbulsara]

I am having the same issue with the below config, can any one help

Configuration register is 0x2142

------------------ show running-config ------------------

Building configuration...

Current configuration : 5589 bytes
!
! Last configuration change at 12:01:31 Perth Fri Nov 25 2022
version 15.1
no service pad
service tcp-keepalives-in
service tcp-keepalives-out
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname PPT-XXX-RTR-01
!
boot-start-marker
boot-end-marker
!
!
enable secret 4 xxxxxxxxxxxxxxxxxxxxxxxx
!
aaa new-model
aaa local authentication attempts max-fail 5
!
!
aaa authentication login default local
!
!
!
!
!
aaa session-id common
clock timezone Perth 8 0
!
no ipv6 cef
no ip source-route
ip cef
!
!
!
ip multicast-routing
ip dhcp bootp ignore
!
!
no ip bootp server
no ip domain lookup
ip domain name xxx.xxxxxxxx.com.xx
multilink bundle-name authenticated
!
!
chat-script TELSTRA-3G-DIALERSTRING "" "ATDT*98*1#" TIMEOUT 30 CONNECT
crypto pki token default removal timeout 0
!
!
license udi pid CISCO2911/K9 sn FGL162911M9
!
!
username CCCCCCC privilege 15 password 0 <removed>
!
!
controller Cellular 0/2
!
ip tftp source-interface Loopback0
ip ssh authentication-retries 5
ip ssh version 2
!
!
!
!
interface Loopback0
description Management and MSDP Address
ip address 10.54.255.4 255.255.255.255
!
interface Loopback99
description Anycast Multicast RP Address
ip address 10.54.255.254 255.255.255.255
!
interface Tunnel2
ip address 10.54.254.29 255.255.255.248
ip pim sparse-dense-mode
tunnel source Dialer1
tunnel destination 10.54.254.254
!
interface Embedded-Service-Engine0/0
no ip address
shutdown
!
interface GigabitEthernet0/0
description MW To Tilley East
bandwidth 100000
ip address 10.54.254.20 255.255.255.248
ip pim sparse-dense-mode
ip igmp version 3
ip ospf authentication message-digest
ip ospf authentication-key <removed>
ip ospf dead-interval 3
ip ospf hello-interval 1
shutdown
duplex auto
speed auto
!
interface GigabitEthernet0/1
description TELSTRA N9xxxxxR
bandwidth 2000
ip address 10.54.254.249 255.255.255.252
ip pim sparse-dense-mode
ip igmp version 3
shutdown
duplex auto
speed auto
!
interface GigabitEthernet0/2
ip address 10.54.4.1 255.255.255.0
ip pim sparse-dense-mode
ip irdp
ip igmp version 3
shutdown
duplex auto
speed auto
!
interface GigabitEthernet0/1/0
description Tait 9100
no ip address
no cdp enable
spanning-tree portfast
!
interface GigabitEthernet0/1/1
description CXC Controller
no ip address
no cdp enable
spanning-tree portfast
!
interface GigabitEthernet0/1/2
description Sensor Probe
no ip address
no cdp enable
spanning-tree portfast
!
interface GigabitEthernet0/1/3
description VF MUX
no ip address
no cdp enable
spanning-tree portfast
!
interface GigabitEthernet0/1/4
no ip address
no cdp enable
spanning-tree portfast
!
interface GigabitEthernet0/1/5
description Interconnect to Gi0/2
no ip address
no cdp enable
spanning-tree portfast
!
interface GigabitEthernet0/1/6
no ip address
no cdp enable
spanning-tree portfast
!
interface GigabitEthernet0/1/7
no ip address
no cdp enable
spanning-tree portfast
!
interface Cellular0/2/0
description *** Telstra Next-G HWIC ***
no ip address
encapsulation ppp
dialer in-band
dialer pool-member 1
async mode interactive
!
interface Cellular0/2/1
no ip address
encapsulation ppp
!
interface Vlan1
no ip address
ip pim sparse-dense-mode
ip igmp version 3
shutdown
no autostate
!
interface Dialer
description TELSTRA-3G
ip address negotiated
ip virtual-reassembly in
encapsulation ppp
dialer pool 1
dialer idle-timeout 0 inbound
dialer string TELSTRA-3G-DIALERSTRING
dialer persistent
fair-queue
ppp authentication chap callin
ppp chap hostname xxxxxxxxxxx@xx.xxxxxxxxxx.com.xx
ppp chap password 0 T3l@@@@@@0xxx$rt
ppp ipcp dns request
no cdp enable
!
router ospf 1
router-id 64.51.3.4
passive-interface default
no passive-interface GigabitEthernet0/0
no passive-interface Tunnel2
network 10.54.0.0 0.0.255.255 area 0
default-information originate
!
ip forward-protocol nd
!
ip pim rp-address 10.54.255.254
ip msdp peer 10.54.255.1 connect-source Loopback0
ip msdp keepalive 10.54.255.1 5 15
ip msdp peer 10.54.255.2 connect-source Loopback0
ip msdp keepalive 10.54.255.2 5 15
ip msdp peer 10.54.255.3 connect-source Loopback0
ip msdp keepalive 10.54.255.3 5 15
ip msdp peer 10.54.255.5 connect-source Loopback0
ip msdp keepalive 10.54.255.5 5 15
ip msdp cache-sa-state
ip msdp originator-id Loopback0
ip msdp timer 5
no ip http server
no ip http secure-server
!
ip route 0.0.0.0 0.0.0.0 Tunnel2
ip route 10.54.254.254 255.255.255.255 Dialer1 200
!
logging source-interface Loopback0
!
route-map PREPEND permit 10
set as-path prepend 64514 64514
!
!
snmp-server community <removed> RO
snmp-server community <removed> RO
snmp-server location (VMR) House
!
!
!
control-plane
!
!
banner exec ^C
*************************************************
* Logged in: KRTRASTS01 (10.54.255.4) House *
*************************************************
^C
banner motd ^C
Tait approved router
^C
!
line con 0
logging synchronous
line aux 0
line 2
no activation-character
no exec
transport preferred none
transport input all
transport output pad telnet rlogin lapb-ta mop udptn v120 ssh
stopbits 1
line 0/2/0
session-timeout 20
exec-timeout 0 0
script dialer TELSTRA-3G-DIALERSTRING
modem InOut
no exec
transport input all
rxspeed 7200000
txspeed 5760000
line 0/2/1
no exec
rxspeed 7200000
txspeed 5760000
line vty 0 4
logging synchronous
transport input all
line vty 5 15
logging synchronous
transport input all
!
scheduler allocate 20000 1000
ntp source Loopback0
ntp server 10.54.1.1
end