[nsp] Maximum Virtual Circuit limit on the NM-4T1-IMA card?

[Scott Lambert]

Hello everyone,

I just inherited admin duties at a small ISP in a rural area which has
been doing DSL service with ATM circuits from two telcos.  We terminate
the PPPoX sessions on a Cisco 3660.

I have just found a problem with provisioning more virtual circuits for
the telco which comes into us via two t1's on a NM-4T1-IMA card.

router(config)#int atm6/ima1
router(config-if)#pvc newvc 1/184
%ATM: Exceeded the VC limit. Max VCs allowed is 255

I'm new to the DSL business in general; so wasn't even aware this could
be a problem when I took over a month ago.  I was hoping I could wade
around in the shallow end of the pool, copy and pasting configs until
I get the rest of the place under control in another month or two.  It
appears that I've been towed out to sea. :-)

I found a data sheet for this adapter at:

http://www.cisco.com/en/US/products/hw/routers/ps259/products_data_sheet09186a00801aa726.html

That data sheet seems to say that I can support 255 VCs per T1 in use
on the IMA adaptor.  I have two T1's hooked into it, but only have VCs
configured on one IMA group, int ATM6/IMA1.  That makes me think that
with just a little configuration magic, I may be able to add another 255
VCs.  I hope.

If anyone has any suggestions, I'd really appreciate the help.

Possibly relevant data from my RANCID repository...

!Chassis type: 3660 - a 3600 router
!CPU: R527x, R527x CPU at 225Mhz, impl 40, Rev 10.0, 2048KB L2 Cache
!
!Memory: main 223232K/38912K
!Memory: nvram 125K
!Memory: pcmcia  Slot0 4096K
!
!Image: Software: C3660-IS-M, 12.2(15)ZJ3, EARLY DEPLOYMENT RELEASE SOFTWARE (fc2)
!Image: Compiled: Thu 25-Sep-03 22:22 by eaarmas
!Image: flash:c3660-is-mz.122-15.ZJ3.bin
!
!Slot 6: type IMA 4 port T1, 4 ports
!Slot 6: hvers 1.0 rev C0
!Slot 6: part 800-03974-03, stripped the serial no.
!
interface ATM6/0
 description "BLAHTELCO 1ST DSL BACKBONE ######"
 no ip address
 no atm ilmi-keepalive
 ima-group 1
 scrambling-payload
!
interface ATM6/1
 description "BLAHTELCO 2ND DSL BACKBONE ######"
 no ip address
 no atm ilmi-keepalive
 ima-group 1
 scrambling-payload
!
interface ATM6/2
 no ip address
 shutdown
 no atm ilmi-keepalive
 no scrambling-payload
!
interface ATM6/3
 no ip address
 shutdown
 no atm ilmi-keepalive
 no scrambling-payload
!
interface ATM6/IMA1
 no ip address
 ip policy route-map pastdue
 no atm ilmi-keepalive
 pvc vc1 1/32 
  class-vc pppoa
 !
 pvc vc2 1/33 
  class-vc ppooe

-- 
Scott Lambert                    KC5MLE                       Unix SysAdmin
lambert at lambertfam.org