Multilink question

[jduawa]

We set up multilink with 2 T1s from our ISP....when i do show ppp multilink on the router this is what i get
INTERNET#show ppp multilink

Multilink1, bundle name is Dnvr-L3-7206-Edge2
0 lost fragments, 0 reordered, 0 unassigned
0 discarded, 0 lost received, 42/255 load
0x0 received sequence, 0x0 sent sequence
Member links: 1 active, 1 inactive (max not set, min not set)
Serial1/1
Serial1/2 (inactive)
How can we have it so both t1's are active ?
We dont want it so that the second one is active after the first reaches its limit we just want a fat 3.088 Mbps pipe.
thanks

 

[writemem]

I believe in order for this to work as a true multilink your ISP needs to configure it on their access router as well. you must also be sure that both t's are set for encap ppp, ppp-multilink and multilink-group x. where x is the group number. In this case most likely 1. I would lean twords your isp not having these t-1's setup as a multilink on their side. could you include more info ("sh run int s1/1" and "sh run int s1/2" and a "sh run int m1" omitting any sensitive info of course). hope this helps
Mark

 

[jduawa]

The isp should have it setup right seeing as though they told us to use multilink....
INTERNET#sh run int s1/1
Building configuration...

Current configuration:
!
interface Serial1/1
no ip address
encapsulation ppp
no fair-queue
ppp chap hostname ARC-T1
ppp multilink
multilink-group 1
end

INTERNET#sh run int s1/2
Building configuration...

Current configuration:
!
interface Serial1/2
no ip address
encapsulation ppp
no fair-queue
ppp chap hostname ARC-T1
ppp multilink
multilink-group 1
end

Current configuration:
!
interface Multilink1
ip address x.x.x.38 255.255.255.252
priority-group 1
no cdp enable
ppp chap hostname ARC-T1
ppp multilink
multilink load-threshold 3 either
multilink-group 1
end

 

[jduawa]

INTERNET#sh ppp mul

Multilink1, bundle name is Dnvr-L3-7206-Edge2
0 lost fragments, 0 reordered, 0 unassigned
0 discarded, 0 lost received, 61/255 load
0x0 received sequence, 0x0 sent sequence
Member links: 1 active, 1 inactive (max not set, min not set)
Serial1/1
Serial1/2 (inactive)

 

[writemem]

I have a Multilink in service on my network and i don't use the "multilink load-threshold 3 either" command. i took a look at cisco's site and it seems like that tells it to add the multilink after a specific load is reached. by nature of that it won't allow both to be up at all times. this was originally designed for isdn where you only want to add bandwidth when needed because there was a per minute cost. i would try removing that statement i think you'll see the s1/2 come active. also i see the priority-group command there what type of queueing are you doing. and do you want to queue. let me know.
Mark

 

[jduawa]

took it out and still inactive
INTERNET#sho run int m1
Building configuration...

Current configuration:
!
interface Multilink1
ip address 216.241.188.38 255.255.255.252
priority-group 1
no cdp enable
ppp chap hostname ARC-T1
ppp multilink
multilink-group 1
end

INTERNET#sh ppp mul

Multilink1, bundle name is Dnvr-L3-7206-Edge2
0 lost fragments, 0 reordered, 0 unassigned
0 discarded, 0 lost received, 33/255 load
0x0 received sequence, 0x0 sent sequence
Member links: 1 active, 1 inactive (max not set, min not set)
Serial1/1
Serial1/2 (inactive)

 

[writemem]

ok try this
conf t
int m1
multilink min-links 2


i would leave the load threshold command out still. i just don't think it's needed. the above command will force the multilink to make both active. silly question you have verified that s1/2 is up up right?

 

[jduawa]

Yes s1/2 is up

INTERNET#sh int s1/2
Serial1/2 is up, line protocol is down
Hardware is M4T
MTU 1500 bytes, BW 2048 Kbit, DLY 20000 usec,
reliability 129/255, txload 1/255, rxload 1/255
Encapsulation PPP, crc 16, loopback not set
Keepalive set (10 sec)
LCP Listen, multilink Closed
Closed: CDPCP
Last input never, output 00:00:16, output hang never
Last clearing of "show interface" counters 13:23:08
Queueing strategy: fifo
Output queue 0/40, 0 drops; input queue 0/75, 0 drops
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
9912 input errors, 9213 CRC, 0 frame, 242 overrun, 0 ignored, 457 abort
10197 packets output, 275319 bytes, 0 underruns
0 output errors, 0 collisions, 928 interface resets
0 output buffer failures, 0 output buffers swapped out
928 carrier transitions DCD=up DSR=up DTR=up RTS=up CTS=up


INTERNET#show ppp mul

Multilink1, bundle name is Dnvr-L3-7206-Edge2
0 lost fragments, 0 reordered, 0 unassigned
0 discarded, 0 lost received, 39/255 load
0x0 received sequence, 0x0 sent sequence
Member links: 1 active, 1 inactive (max not set, min 2)
Serial1/1
Serial1/2 (inactive)

INTERNET#sh run int m1
Building configuration...

Current configuration:
!
interface Multilink1
ip address x.x.x.38 255.255.255.252
priority-group 1
no cdp enable
ppp chap hostname ARC-T1
ppp multilink
multilink min-links 2
multilink-group 1
end

Thanks for the assistance

 

[writemem]

well there you have it. bring up that second t-1 and your multilink will be 2xt1. sorry i should have checked that first. wow look at all those crc errors. good luck
Mark

 

[jduawa]

Yeah i just noticed that, i saw serial was up and did not look at the line protocol....thanks for the help

 

[jduawa]

Thanks for the help...Turns out we had a bad dsu, which is why serial 2 line protocol was down

 

[writemem]

cool glad i could help. not sure that the multilink min-links 2 command is neccessary at this point but shouldn't hurt. your call if you want to remove it.

Mark