[c-nsp] PPP Mulitilink on 3620

[David Simmons - EliteUKServe.Net]

Hi,

We have a link for a service provider and they insisted on shoving in a fibre 
to our building then splitting the fibre into 4 x 2mb tribs. Then from there 
we have 4 x X25 into a 3620 with a NM-4T. Now our other providers give us LES 
circuits etc.. We run BGP.

It has all worked fine untill the traffic started rising to say nearly 4MB on 
this line. Then the CPU usage goes bananas on this router. Packets start 
being lost and we get very high ping times. All this router does is the PPP 
multilink and is then directly connect to a 7200 ... which handles the BGP 
etc.

My question is ... and I will admit to not being extremely cisco knowledgable 
(this was dumped on my desk) ... is is this simply a matter of the router not 
being able to handle whats chucked at it ... or could there be things we are 
doing or not doing right with the multilink?

Hoping you may have some ideas.

Regards,

David SImmons

interface Multilink1
 description ### Multilink (4 Serials) ###
 bandwidth 8192
 ip address xx.xx.xx.xx 255.255.255.252
 ip access-group 151 in
 ip access-group 101 out
 ppp multilink
 multilink-group 1

[cut]

interface Serial1/0
 description ### Trib 1 ###
 bandwidth 2048
 no ip address
 no ip proxy-arp
 encapsulation ppp
 no ip mroute-cache
 serial restart-delay 0
 ppp multilink
 multilink-group 1
!         
interface Serial1/1
 description ### Trib 2 ###
 bandwidth 2048
 no ip address
 no ip proxy-arp
 encapsulation ppp
 no ip mroute-cache
 serial restart-delay 0
 ppp multilink
 multilink-group 1
!         
interface Serial1/2
 description ### Trib 3 ###
 bandwidth 2048
 no ip address
 no ip proxy-arp
 encapsulation ppp
 no ip mroute-cache
 serial restart-delay 0
 ppp multilink
 multilink-group 1
!         
interface Serial1/3
 description ### Trib 4 ###
 bandwidth 2048
 no ip address
 no ip proxy-arp
 encapsulation ppp
 no ip mroute-cache
 serial restart-delay 0
 ppp multilink
 multilink-group 1

[cut]

ip classless
ip route 0.0.0.0 0.0.0.0 Multilink1
ip route xx.xx.xx.0 255.255.240.0 xx.xx.xx.26
ip route xx.xx.xx.1 255.255.255.255 xx.xx.xx.26