[cisco-nas] Problems with multilink PPP/ISDN

[Regnar Bang Lyngsø]

Hi,

I am experiencing problems that I can't understand.

I have a Cisco 3600 with an ISDN PRI and I can't get ISDN-2 Multilink PPP
(128K) to work and I really don't know why.

Everything works fine with a single 64K ISDN channel. Also, multilink PPP
with one ISDN channel and an analog modem connection works fine.

Clients are various Windows Workstations with Lasat and Zyxel ISDN modems.

Radius server is MS IAS with the following parameters set:
Framed-Protocol: PPP
Service-type: Framed
Filter-Id: depending on profile

The following is debug output (I would like to know what the "Ignoring bad
ACK!" message means):

00:13:14: %LINK-3-UPDOWN: Interface Serial3/0:0, changed state to up
00:13:15: %LINK-3-UPDOWN: Interface Serial3/0:1, changed state to up
00:13:15: %ISDN-6-CONNECT: Interface Serial3/0:0 is now connected to 443
00:13:17: Se3/0:0 LCP: Ignoring bad ACK!
00:13:19: Se3/0:0 EVT: Packet suspended unexpectedly
00:13:21: %ISDN-6-CONNECT: Interface Serial3/0:1 is now connected to 443
00:13:22: Se3/0:0 LCP: Ignoring bad ACK!
00:13:25: %ISDN-6-DISCONNECT: Interface Serial3/0:1  disconnected from 443
, call lasted 10 seconds
00:13:25: %LINK-3-UPDOWN: Interface Serial3/0:1, changed state to down
00:13:25: %ISDN-6-DISCONNECT: Interface Serial3/0:0  disconnected from 443
071f1c, call lasted 10 seconds
00:13:25: %LINK-3-UPDOWN: Interface Serial3/0:0, changed state to down

Configuration:
!RANCID-CONTENT-TYPE: cisco
!
!Chassis type: 3640 - a 3600 router
!CPU: R4700
!
!Memory: main 93184K/5120K
!Memory: nvram 125K
!Memory: flash partition 24576K
!Memory: flash partition 8192K
!
!Power: Redundant Power System is not present.
!
!Image: Software: C3640-IS-M, 12.2(13)T,  RELEASE SOFTWARE (fc1)
!Image: Compiled: Fri 15-Nov-02 23:41 by ccai
!Image: flash:c3640-is-mz.122-13.T.bin
!
!ROM Bootstrap: Version 11.1(17)AA, EARLY DEPLOYMENT RELEASE SOFTWARE (fc2)
!
!
!Flash: System flash directory, partition 1:
!Flash: File  Length   Name/status
!Flash:   1   16705296  c3640-is-mz.122-13.T.bin
!Flash: [16705360 bytes used, 8460464 available, 25165824 total]
!Flash: 24576K bytes of processor board System flash (Read/Write)
!Flash: System flash directory, partition 2:
!Flash: File  Length   Name/status
!Flash:   1   468529   mica-modem-pw.2.9.4.0.bin
!Flash: [468596 bytes used, 7920012 available, 8388608 total]
!Flash: 8192K bytes of processor board System flash (Read/Write)
!
!Flash: nvram: Directory of nvram:/
!Flash: nvram:   121  -rw-        5503              <no date>
startup-config
!Flash: nvram:   122  ----          27              <no date>
private-config
!Flash: nvram:     1  -rw-           0              <no date>
ifIndex-table
!Flash: nvram: 129016 bytes total (122410 bytes free)
!
!Interface: FastEthernet0/0, AMD Am79c971
!Interface: Ethernet1/0, AMD Unknown
!
!Slot 0: hvers 1.0 rev B0
!Slot 0: part 800-03490-01, serial 7719046
!
!Slot 1: type Combo 1E, 1R, 2W, 4 ports
!Slot 1: hvers 1.0 rev A0
!Slot 1: part 800-01223-02, serial 7858403
!
!Slot 2: type Digital Modems, 12 ports
!Slot 2: hvers 0.2 rev A0
!Slot 2: part 800-02316-03, serial 12886220
!
!Slot 3: type CE1 Balanced, 1 ports
!Slot 3: hvers 1.1 rev A0
!Slot 3: part 800-01234-04, serial 11306628
!
!VTP: VTP Version                     : 2
!VTP: Configuration Revision          : 0
!VTP: Maximum VLANs supported locally : 256
!VTP: Number of existing VLANs        : 5
!VTP: VTP Operating Mode              : Server
!VTP: VTP Domain Name                 :
!VTP: VTP Pruning Mode                : Disabled
!VTP: VTP V2 Mode                     : Disabled
!VTP: VTP Traps Generation            : Disabled
!VTP: MD5 digest                      : 0xBF 0x86 0x94 0x45 0xFC 0xDF 0xB5
0x70
!VTP: Local updater ID is 192.168.1.181 on interface Fa0/0 (first interface
found)
!
!VLAN: % Ambiguous command:  "show vlan"
!
!
config-register 0x101
This command has no effect on this line; use modem AT commands instead

!
config-register 0x101
version 12.2
service timestamps debug uptime
service timestamps log uptime
service password-encryption
!
hostname "ao-srv01-dia01"
!
logging buffered 4096 debugging
enable secret 5 <removed>
!
!username admin password <removed>
!username ao password <removed>
!username dialin password <removed>
modem country mica denmark
aaa new-model
!
!
aaa group server radius AO
!
aaa authentication login NO_AUTHEN local
aaa authentication ppp default group radius
aaa session-id common
ip subnet-zero
!
!
no ip dhcp conflict logging
ip dhcp excluded-address 192.168.187.1
ip dhcp excluded-address 192.168.187.254
!
ip dhcp pool 0
   network 192.168.187.0 255.255.255.0
   domain-name NTDOMAIN1
   dns-server 192.168.1.15
   netbios-name-server 192.168.1.15
   netbios-node-type h-node
   default-router 192.168.187.254
!
ip dhcp-server 192.168.187.254
virtual-profile virtual-template 1
multilink virtual-template 1
isdn switch-type primary-net5
!
!
!
!
!
!
!
!
!
!
!
mta receive maximum-recipients 0
partition flash 2 24 8
!
!
controller E1 3/0
 pri-group timeslots 1-30
!
!
!
!
interface Loopback0
 ip address 192.168.187.254 255.255.255.0
!
interface FastEthernet0/0
 ip address 192.168.1.181 255.255.255.0
 duplex auto
 speed auto
!
interface Ethernet1/0
 no ip address
 shutdown
 half-duplex
 no cdp enable
!
interface TokenRing1/0
 no ip address
 shutdown
 ring-speed 16
 no cdp enable
!
interface Serial3/0:15
 no ip address
 encapsulation ppp
 ip mroute-cache
 dialer rotary-group 1
 dialer-group 1
 autodetect encapsulation ppp v120
 isdn switch-type primary-net5
 isdn incoming-voice modem
 peer default ip address dhcp
 no cdp enable
 ppp authentication ms-chap-v2 chap pap ms-chap
 ppp multilink
!
interface Virtual-Template1
 ip unnumbered Loopback0
 peer default ip address dhcp
 ppp authentication ms-chap-v2 chap pap ms-chap
 ppp multilink
!
interface Group-Async1
 ip unnumbered Loopback0
 encapsulation ppp
 ip tcp header-compression
 async mode dedicated
 peer default ip address dhcp
 no keepalive
 ppp authentication ms-chap-v2 chap pap ms-chap
 ppp multilink
 group-range 65 76
!
interface Dialer1
 ip unnumbered Loopback0
 encapsulation ppp
 dialer in-band
 dialer idle-timeout 3600
 dialer-group 1
 peer default ip address dhcp
 no cdp enable
 ppp authentication ms-chap-v2 chap pap ms-chap
 ppp multilink
!
ip classless
ip route 0.0.0.0 0.0.0.0 192.168.1.250
no ip http server
!
!
!
logging history debugging
logging source-interface Loopback0
logging 192.168.1.18
access-list 101 blah blah
access-list 102 blah blah
access-list 103 blah blah
access-list 104 blah blah
dialer-list 1 protocol ip permit
!
snmp-server community <skipped> RW
snmp-server community <skipped> RO
snmp-server location "AUDK M.P. Bruuns Gade 27, Serverrum 1"
snmp-server contact "Network Administrator @ AUDK +45 87 30 60 00"
snmp-server enable traps tty
radius-server host 192.168.1.26 auth-port 1645 acct-port 1646
!radius-server key <removed>
radius-server authorization permit missing Service-Type
call rsvp-sync
!
!
mgcp profile default
!
!
!
dial-peer cor custom
!
!
!
!
line con 0
 login authentication NO_AUTHEN
line 65 76
 flush-at-activation
 modem InOut
 autoselect during-login
 autoselect ppp
line aux 0
line vty 0 4
! password <removed>
!
!
end


Regards
--
Regnar Bang Lyngsø, Network Administrator
Aarhus United Denmark
M.P. Bruuns Gade 27, DK-8100 Århus C, Denmark
Email: mailto:regnar.lyngso at aarhusunited.com
Phone: +45 87 30 61 65 Mobile: +45 40 45 08 89