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HELP! Multilink PPP w/3 T1s and a seperate 4th T1

I've got a Cisco 3640 with 128M/32M RAM. There are 2x NM-2FE2W and 4x WIC-1DSU-T1 cards installed. The configurations for the interfaces are below. I have 4 point-to-point T1s coming into this router. 3 T1s are coming from another 3640 at one office (A) and the other T1 is coming from a 2514 at another office (B). I control all 3 routers.

I've been using Multilink PPP to give my users a 3M pipe over 2 of the T1s at office A. I had a 3rd T1 installed in order to bump it up to

4.5M. Office B is serviced by a the single (fourth) T1.

Before the new T1 was installed everything worked fine (2 T1s using MLPPP to office A and 1 T1 to office B). Now, with all 4 lines running, the 3rd MLPPP line won't work (see 'sho int' and 'sho service-module' below) but the original 3 lines work fine.

Now here's where it gets strange. If I remove the card servicing the T1 to office B and boot up the router, all 3 interfaces come up and MLPPP works great, providing a 4.5M pipe. Once I shut down the router and reinsert the card for office B, the 3rd MLPPP lines goes down again. I tried swapping the office B card/cable with the card(s)/cable(s) from the 1st and 2nd MLPPP lines and get the exact same results. Same goes for the card/cable servicing the 3rd MLPPP line.

Am I missing a configuration step? I'm at a loss.

Again, I've swapped WIC cards, NM cards, and cables between all interfaces and they all work. I've also tried different slots for the NMs. No difference.

Help! TIA

Rich

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interface Multilink1 ip address A.B.C.D 255.255.255.252 ip route-cache flow fair-queue 64 16 0 no cdp enable ppp multilink ppp multilink fragment delay 10 ppp multilink interleave ppp multilink group 1 ! interface MFR1 no ip address ! interface FastEthernet0/0 ip address E.F.G.H 255.255.255.240 ip route-cache flow speed 100 full-duplex ! interface Serial0/0 bandwidth 1536 no ip address encapsulation ppp fair-queue ppp multilink ppp multilink group 1 ! interface FastEthernet0/1 ip address I.J.K.L 255.255.255.224 speed 100 full-duplex ! interface Serial0/1 bandwidth 1536 no ip address encapsulation ppp fair-queue ppp multilink ppp multilink group 1 ! interface FastEthernet1/0 no ip address speed 100 full-duplex ! interface Serial1/0 bandwidth 1536 no ip address encapsulation ppp fair-queue ppp multilink ppp multilink group 1 ! interface FastEthernet1/1 ip address M.N.O.P 255.255.255.252 secondary ip address Q.R.S.T 255.255.255.128 secondary ip address U.V.W.X 255.255.255.248 speed 100 full-duplex ! interface Serial1/1 ip address Y.Z.A.B 255.255.255.252 no ip mroute-cache autodetect encapsulation ppp

-------------------------------------------------------------------------------- [with all four lines connected]

abc-rtr0#sho int ser 1/0 Serial1/0 is down, line protocol is down Hardware is DSCC4 with integrated T1 CSU/DSU MTU 1500 bytes, BW 1536 Kbit, DLY 20000 usec, reliability 255/255, txload 1/255, rxload 1/255 Encapsulation PPP, LCP Closed, multilink Closed, loopback not set Keepalive set (10 sec) Last input never, output 00:29:20, output hang never Last clearing of "show interface" counters 05:03:07 Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0 Queueing strategy: weighted fair Output queue: 0/1000/64/0 (size/max total/threshold/drops) Conversations 0/1/256 (active/max active/max total) Reserved Conversations 0/0 (allocated/max allocated) Available Bandwidth 1152 kilobits/sec 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 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort 1640 packets output, 47560 bytes, 0 underruns 0 output errors, 0 collisions, 166 interface resets 0 output buffer failures, 0 output buffers swapped out 2 carrier transitions DCD=down DSR=up DTR=up RTS=up CTS=down

abc-rtr0#sho service-mod ser 1/0 Module type is T1/fractional Hardware revision is 0.96, Software revision is 20050811-0.3, Image checksum is 0x80ACD1B3, Protocol revision is 0.1 Receiver has Remote alarm, Framing is ESF, Line Code is B8ZS, Current clock source is line, Fraction has 24 timeslots (64 Kbits/sec each), Net bandwidth is 1536 Kbits/sec. Last module self-test (done at startup): Passed Last clearing of alarm counters 05:03:26 loss of signal : 0, loss of frame : 0, AIS alarm : 0, Remote alarm : 2, current duration 00:29:19 Module access errors : 0, Total Data (last 20 15 minute intervals): 6742 Line Code Violations, 466 Path Code Violations 0 Slip Secs, 25 Fr Loss Secs, 3 Line Err Secs, 0 Degraded Mins 0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 25 Unavail Secs Data in current interval (173 seconds elapsed): 0 Line Code Violations, 0 Path Code Violations 0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins 0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail Secs

abc-rtr0#sho int multi 1 Multilink1 is up, line protocol is up Hardware is multilink group interface Internet address is 64.70.70.253/30 MTU 1500 bytes, BW 3072 Kbit, DLY 100000 usec, reliability 255/255, txload 21/255, rxload 31/255 Encapsulation PPP, LCP Open, multilink Open Open: IPCP, loopback not set Keepalive set (10 sec) DTR is pulsed for 2 seconds on reset Last input 00:00:00, output never, output hang never Last clearing of "show interface" counters 05:04:08 Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops:

62 Queueing strategy: weighted fair Output queue: 0/1000/64/62/26293 (size/max total/threshold/drops/interleaves) Conversations 0/16/16 (active/max active/max total) Reserved Conversations 0/0 (allocated/max allocated) Available Bandwidth 2304 kilobits/sec 5 minute input rate 384000 bits/sec, 266 packets/sec 5 minute output rate 256000 bits/sec, 244 packets/sec 4997912 packets input, 924185971 bytes, 0 no buffer Received 0 broadcasts, 0 runts, 0 giants, 0 throttles 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort 4675985 packets output, 695093405 bytes, 0 underruns 0 output errors, 0 collisions, 2 interface resets 0 output buffer failures, 0 output buffers swapped out 0 carrier transitions
Reply to
rajuliano
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Could be a bad chassis. Have you tried swapping the router with another one? Could also be an IOS bug, what version are you running?

Scott

Reply to
Thrill5

Do anyone know of any script that tweak the registry to disable the wireless NIC when both the wired and wireless NIC is detected.

Pls advise and thanks.

happy.ppp wrote:

Reply to
brink

Sounds like you have been very thorough.

Is logging enabled? What are you seeing there? Memory allocation failures would be logged.

conf t logg buff 50000 logg buff deb end wr

reload sh log

temp#sh mem Head Total(b) Used(b) Free(b) Lowest(b) Largest(b) Processor 81BA60F4 31406860 15146932 16259928 16044380

15376912 I/O 3999C00 6710272 1073388 5636884 5576744 5636308

The most critical value is the "largest".

Along with the sh controllers then post

sh log sh mem ! first few lines sh buff

sh network-clocks ! may not apply to this platform.

Reply to
Bod43

snipped-for-privacy@gmail.com wrote: [snip: trying to do this:

Please view in a fixed-width font such as Courier.

+----------+ | Site A | | | +-+-+-+----+ | | | | | | | | | Qty 3 T1 in MLPPP | | | | | | ++-+-+---+ +--------+ | | | | | HQ | Qty 1 T1 | | | +------------------| Site B | | | | | +--------+ +--------+

[snip]

You are getting a remote alarm. Is the other side Site-A configured properly? (I realize it works when T1 to B is not connected, but worth checking again)

the other thing to consider is that you may have reached a limit. but then why would you get a remote-alarm.... Interesting.

I would investigate the remote alarm first. Make sure there is no loop on the other end for example that's getting thrown up for some reason. you can try to detect the loopback with 'down-when-loop'

Reply to
Hansang Bae

snipped-for-privacy@gmail.com wrote: [snip]

One other thing to consider. Clock source on the T1's. Perhaps you are at just at the edge of clock drift and adding the one additional T1 is killing it?

See Thrill5's post (quoted here: All voice circuits (i.e. a T1) need a clock, but clock is a misnomer for what is really needed, which is a stable oscillator, or a common source for recovering the "clock" of the circuit. Circuits from the SAME carrier can generally share a clock because the carrier will generally have a single "clock source" for all their circuits. If you have 3 T1 from the same carrier, on one of the T1's you would configure "clock source primary" and the rest could be "clock source internal", because the internal clock would be synced to the "primary" line. You can also configure each interface as "clock source line" which is the default. All T1's need a clock source, either your end or their end, and if this is a carrier circuit, than they provide the clock and you need either "clock source line" or "clock source primary" on one T1, and "clock source internal" on the others. The only time you would provide clock by NOT configuring "clock source line" or "clock source primary" is if you were connecting a to a PBX and it was configure to recover clock for that circuit on that T1, or you were running a T1 over your own copper to another device. Since you have the errors described above, you do a clocking issue, and they should be configured as "clock source line".)

Reply to
Hansang Bae

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