I purchased a new Cisco 1721 router in order to replace the old NILE router for FR connection. I found some examples of Cisco 2620 router as below:
EDISON-FR(config)#interfac
EDISON-FR(config-if)#ip address 204.117.5.9 255.255.255.192
EDISON-FR(config-if)#desc Serial0 to FR external CSU/DSU
EDISON-FR(config-if)#no shutdown
EDISON-FR(config-if)#encap
EDISON-FR(config)#interfac
EDISON-FR(config-subif)#de
EDISON-FR(config-subif)#ip
EDISON-FR(config-subif)#fr
EDISON-FR(config)#interfac
EDISON-FR(config-subif)#de
EDISON-FR(config-subif)#ip
EDISON-FR(config-subif)#fr
EDISON-FR(config)#interfac
EDISON-FR(config-subif)#de
EDISON-FR(config-subif)#ip
EDISON-FR(config-subif)#fr
Later another article told me a different example as below:
EDISON-FR(config)#int s0
EDISON-FR(config-if)#encap
EDISON-FR(config-if)#encap
EDISON-FR(config-if)#frame
EDISON-FR(config-if)#frame
EDISON-FR(config-if)#frame
EDISON-FR(config-if)#frame
The major difference is the first example is to assign IP address on serial port and sub-ports and the second example is to map IP address on serial port. Please advise, which one is correct or they are all right but for different router models?
Thanks in advance.
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Most typically, frame-relay is point-to-point and therefore the most appropo config is to use a separate point-to-point sub-interface for each DLCI as depicted in your first example.
If both ends of the frame-relay PVC are Cisco routers, you don't need the IETF at all
You might also want to bring the interface "up"
router(config)#interface serial 0
router(config-if)#no shut
Nice to get response from you, I know you are a top expert here.
I did by the first example but it did not work, then I called CISCO and was told that I should not assign IP address on serial port and sub-ports but should map IP address on serial port by the second example. When I asked him why, I could not get a good answer. I read several articles that use the first example to set up FR, thus I want to understand why I should use the second in this case.
FYI - not all routers use Cisco.
Thanks.
I have done literally thousands of frame-relay deployments and with one single exception, always use the point-to-point sub-interfaces. The single exception was due to replacing an exisiting router that was already set up that way while we moved them to the point-to-point.
First, we have to determine why it did not work.
Assuming that you have a v.35 cable, or a new CSU/DSU to get signal from the telco....
Are these point-to-point PVC's?
Are the remote sites already "live" with working connections?
Here is a typical config for multiple frame-relay sites:
"HQ or Core site"
!
interface serial 0/0
no ip address
no shutdown
encapsulation frame-relay
lmi-type ansi <-- use this ONLY if required by the telco. No entry here means 'autodetect' / default to CISCO
!
interface serial 0/0.30 <-- these sub-if numbers are abitrary. I use the DLCI # for ease
description PVC to SITE2
ip address 192.168.254.1 255.255.255.252
frame-relay interface-dlci 30
!
interface serial 0/0.32
description PCV to SITE3 - Nortel router
ip address 192.168.254.5 255.255.255.252
frame-relay interface-dlci 32 IETF
!
interface serial 0/0.45
description PCV to SITE4
ip address 192.168.254.9 255.255.255.252
frame-relay interface-dlci 45 IETF
!
<etc>
SITE 2 - x all Cisco routers
Interface serial 0/0
no ip address
no shut
encapsulation frame-relay
!
interface serial 0/0.1
description PVC to HQ
ip address 192.168.254.2 255.255.255.252
frame-relay interface-dlci 33
!
SITE4
Interface serial 0/0
no ip address
no shut
encapsulation frame-relay
!
interface serial 0/0.1
description PVC to HQ
ip address 192.168.254.10 255.255.255.252
frame-relay interface-dlci 33
!
Subinterfaces act just like real interfaces. A dropped PVC will drop an interface which is an snmp trap event. Easier to manage. You can do things with subinterfaces that you can't do with maps. You can encrypt on a sub-interface. You can assign access-lists to a subinterface, you can do basically anything that you can do on a 'real' interface. It also makes dynamic routing using EIGRP or OSPF easier because you don't have the split-horizon issues.
I can think of no good reason to use maps vs sub-interfaces.
Some troubleshooting tools include "show interface"
Serial 0/0
Line UP / protocol DOWN = good T1 connection, not getting LMI from the switch
Line UP / protocol UP = good T1 connection, getting LMI from switch
But
Serial 0/0.1 line down/protocol down = wrong DLCI assigned to the subinterface.
'show frame-relay pvc' may show ACTIVE DLCI on serial 0/0, not on the expected Subinterface. If so, change the interface-dlci of that sub-interface to match what you're "seeing" from the switch.
Remember, BOTH sides of the PVC have to be up for the DLCI to become ACTIVE.
First, it is right that I am replacing an existing router. There are four routers with the same configuration. I think it is the point why I still need to use the old way to have FR work.
Second, I need a customized cable to get signal from my ISP after confiming with ISP and CISCO. My cable is customized because a T1 supports both voice and data.
Third, three remote sites still use the old routers to work lively.
Fourth, I read your typical config for multiple frame-relay sites. One question is if I should assign IP address on the serial 0/0 in addition to all sub-serial interfaces.
Thanks.
Easy part first. No, you don't need to assign an IP address to the major serial interface, only to the point-to-point sub-interfaces
For easier migration from old config to new config, setup one sub-interface as point-to-multipoint, example:
interface serial 0/0
encapsulation frame-relay
no ip address
!
interface serial 0/0.22 point-to-multipoint
ip address 204.117.65.69 255.255.255.192
frame-relay map ip 204.117.65.65 30 broadcast IETF
frame-relay map ip 204.117.65.67 32 broadcast
frame-relay map ip 204.117.65.70 45 broadcast IETF
!
interface serial 0/0.33 point-to-point
Description point-to-point to SITE 1
ip address 192.168.222.1 255.255.255.252
frame-relay interface-dlci 33
!
I still don't understand your requirement for a customized cable. If your T1 is bringing in both data and voice, then the DSU is providing the drop-insert functions, splitting data to a v.35 interface and voice to a DsX port. The v.35 - router cable should be standard Cisco issue.
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Answer for Membership
by: slu2003Posted on 2003-11-26 at 07:45:03ID: 9825262
Here are some information for reference:
EDISON-FR#show conf
Using 1902 out of 29688 bytes
!
! Last configuration change at 12:29:56 UTC Tue Nov 25 2003
! NVRAM config last updated at 12:30:03 UTC Tue Nov 25 2003
!
version 12.3
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname EDISON-FR
!
boot system flash
boot system tftp 198.69.18.157 255.255.255.255
logging buffered 52000 debugging
enable secret 5 $1$D1hF$DbXeip35LjNUCpvOVw
enable password xxx
!
username sdm privilege 15 password 0 xxx
ip subnet-zero
!
interface FastEthernet0
description FastEthernet0 to LAN switch
ip address 198.69.18.6 255.255.255.0
speed auto
half-duplex
!
interface Serial0
description Serial0 to FR external CSU/DSU
ip address 204.117.65.69 255.255.255.192
encapsulation frame-relay IETF
no fair-queue
frame-relay map ip 204.117.65.65 30 broadcast
frame-relay map ip 204.117.65.67 32 broadcast
frame-relay map ip 204.117.65.70 45 broadcast
frame-relay interface-dlci 33
!
ip classless
ip route 0.0.0.0 0.0.0.0 198.69.18.4
ip route 10.0.1.0 255.255.255.0 198.69.18.2
ip route 10.0.2.0 255.255.255.0 198.69.18.3
ip route 10.69.19.0 255.255.255.0 204.117.65.70
ip route 10.69.218.0 255.255.255.0 204.117.65.65
ip route 198.69.16.0 255.255.255.0 204.117.65.65
ip route 198.69.17.0 255.255.255.0 204.117.65.65
ip route 198.69.18.0 255.255.255.0 FastEthernet0
ip route 204.117.65.64 255.255.255.192 Serial0
ip route 208.11.156.0 255.255.255.0 204.117.65.65
ip route 208.11.157.0 255.255.255.0 204.117.65.65
ip route 208.11.158.0 255.255.255.0 204.117.65.68
ip route 208.11.159.0 255.255.255.0 204.117.65.65
ip http server
ip http authentication local
!
snmp-server community public RO
snmp-server enable traps tty
banner motd
Welcome to the FR router in NJ ****************
!
line con 0
line aux 0
line vty 0 4
privilege level 15
password cisco
login local
transport input telnet
!
no scheduler allocate
!
end
EDISON-FR#show fr map
Serial0 (down): ip 204.117.65.65 dlci 30(0x1E,0x4E0), static,
broadcast,
IETF, status defined, inactive
Serial0 (down): ip 204.117.65.67 dlci 32(0x20,0x800), static,
broadcast,
IETF, status defined, inactive
Serial0 (down): ip 204.117.65.70 dlci 45(0x2D,0x8D0), static,
broadcast,
IETF, status defined, inactive
EDISON-FR#show fr pvc
PVC Statistics for interface Serial0 (Frame Relay DTE)
Active Inactive Deleted Static
Local 0 4 0 0
Switched 0 0 0 0
Unused 0 0 0 0
DLCI = 30, DLCI USAGE = LOCAL, PVC STATUS = INACTIVE, INTERFACE = Serial0
input pkts 0 output pkts 0 in bytes 0
out bytes 0 dropped pkts 0 in pkts dropped 0
out pkts dropped 0 out bytes dropped 0
in FECN pkts 0 in BECN pkts 0 out FECN pkts 0
out BECN pkts 0 in DE pkts 0 out DE pkts 0
out bcast pkts 0 out bcast bytes 0
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
pvc create time 00:10:50, last time pvc status changed 00:10:50
DLCI = 32, DLCI USAGE = LOCAL, PVC STATUS = INACTIVE, INTERFACE = Serial0
input pkts 0 output pkts 0 in bytes 0
out bytes 0 dropped pkts 0 in pkts dropped 0
out pkts dropped 0 out bytes dropped 0
in FECN pkts 0 in BECN pkts 0 out FECN pkts 0
out BECN pkts 0 in DE pkts 0 out DE pkts 0
out bcast pkts 0 out bcast bytes 0
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
pvc create time 00:11:06, last time pvc status changed 00:11:06
DLCI = 33, DLCI USAGE = LOCAL, PVC STATUS = INACTIVE, INTERFACE = Serial0
input pkts 0 output pkts 0 in bytes 0
out bytes 0 dropped pkts 0 in pkts dropped 0
out pkts dropped 0 out bytes dropped 0
in FECN pkts 0 in BECN pkts 0 out FECN pkts 0
out BECN pkts 0 in DE pkts 0 out DE pkts 0
out bcast pkts 0 out bcast bytes 0
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
pvc create time 00:11:16, last time pvc status changed 00:11:16
DLCI = 45, DLCI USAGE = LOCAL, PVC STATUS = INACTIVE, INTERFACE = Serial0
input pkts 0 output pkts 0 in bytes 0
out bytes 0 dropped pkts 0 in pkts dropped 0
out pkts dropped 0 out bytes dropped 0
in FECN pkts 0 in BECN pkts 0 out FECN pkts 0
out BECN pkts 0 in DE pkts 0 out DE pkts 0
out bcast pkts 0 out bcast bytes 0
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
pvc create time 00:11:26, last time pvc status changed 00:11:26
EDISON-FR#show fr lmi
LMI Statistics for interface Serial0 (Frame Relay DTE) LMI TYPE = CISCO
Invalid Unnumbered info 0 Invalid Prot Disc 0
Invalid dummy Call Ref 0 Invalid Msg Type 0
Invalid Status Message 0 Invalid Lock Shift 0
Invalid Information ID 0 Invalid Report IE Len 0
Invalid Report Request 0 Invalid Keep IE Len 0
Num Status Enq. Sent 0 Num Status msgs Rcvd 0
Num Update Status Rcvd 0 Num Status Timeouts 0
Last Full Status Req never Last Full Status Rcvd never