I've been looking everywhere but can't seem to find the answer.
I am taking my ccna exams in a month's time and I am currently learning about frame-relay.
I have been looking everywhere but how do I know the DLCI that has been assigned to my local router? I know about using several show command e.g. show frame map, show fram lmi, show frame pvc , show run etc. but these only show the DLCI of the REMOTE routers.
I guess my question stems from if there is already a preconfigured and fully operating frame-relay router being used and I as a new engineer wants to know the DLCI that is assigned to it, how do I know. I mean are there some other show commands that I have missed or is it a case of me contacting my service provider to know?
The "sh frame-relay map" will show you what your local dlci is as well as "show frame-relay pvc":
R3#sh frame-relay pvc
PVC Statistics for interface Serial0/0 (Frame Relay DTE)
Active Inactive Deleted Static
Local 1 0 0 0
Switched 0 0 0 0
Unused 0 0 0 0
DLCI = 103, DLCI USAGE = LOCAL, PVC STATUS = ACTIVE, INTERFACE = Serial0/0
input pkts 17 output pkts 27 in bytes 1100
out bytes 1592 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 1 out bcast bytes 34
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
Shaping adapts to BECN
pvc create time 00:10:21, last time pvc status changed 00:10:01
Show frame-relay map:
R3#sh frame-rel map
Serial0/0 (up): ip 172.23.0.2 dlci 103(0x67,0x1870), dynamic,
broadcast,, status defined, active
ip address 172.23.0.3 255.255.255.0
clock rate 64000
frame-relay interface-dlci 103
but I thought this command:
" DLCI = 103, DLCI USAGE = LOCAL, PVC STATUS = ACTIVE, INTERFACE = Serial0/0"
show the DLCI of the a remote router, in other words a router that I have formed a PVC relationship with.
So in this example dlci 103 will be the dlci of a different route. hence, I am able to to create a map if needed?
the DLCI you see here is the DLCI affected to the router by the Frame-relay switch through LMI and it will be used to reach distant prefixes.
It is a common mistake to believe that the DLCI that you see in commands such as show frame-relay pvc is the remote DLCI. But the DLCI shown in the command is in fact the local DLCI.
Hi Cadet Alain,
Thanks once again. I don't want to sound dumb or question your knowledge but according to the photos I have attached below (sorry if not the best quality) it is different to what you are telling me. The photos are from ccna icnd 2 book.
From the first photo we see the network diagram with 4 routers (of course in multipoint). I can see that altanta has dlci 51, charlotte dlci 52, nashville dlci 53 & boston dlci 54.
The second photo shows the output from Atlanta "show frame-relay pvc" command. from this I can see all the dlcis for the other three routers who have now formed a pvc relationship with Atlanta.however, the output does not show atlanta's own personal DLCI.
So what I am really asking is assuming we didnt know from the photos that atlanta is is using dlci51 how will we ever know? and in a real world scenario i might be new to company and need to log into a local router to find its own personal dlci. how can i know?
Thanks for your patience.
It is a shame when books like this make a mistake. But the page that you show is not correct. Does the book include the configuration for that example in addition to the show command output? It might be helpful to see the configuration and if we did it might help to clarify the situation.
Thank you for the additional information. The configuration is quite plain and does clearly show what is going on. The interface command frame-relay interface-dlci n defines the local DLCI. And it makes it quite clear that what is in the drawing does not match what is in the configuration. On Atlanta the DLCIs are 52, 53, and 54. And these are the local DLCI values and not the values on the remote routers as shown in the drawing.
I just checked the brand new book out this year by Wendell Odom, CCNA ICND2 3rd edition and it has the exact same config and diagram as shown above (now Chapter 16).
Could you post how it should be configured.
I would say that there is not any problem with how it is configured, which should work quite well. The problem is with the drawing which seems to show 52, 53, and 54 as part of the remote routers and shows only 51 as associated with Atlanta router. When you look at the configuration and at the output of the show commands it is clear that there are 3 DLCIs on Atlanta and probably only one on the three remote routers. So change the drawing and all would be well.