Need help!
I have two serial t1's bonded for multilink PPP with Sprint on a 12.4 IOS 2811 (Sprint's PE is a Cisco router as well).
The symptoms we see are download speeds are 1.3Mbit and upload speeds are 3.0Mbit. If I shut one serial interface down and run the same test I get 1.2Mbit down/1.3Mbit up. If I bring that one back up and shut the other one down I get roughly 1.2Mbit down/1.2Mbit up - (during all these speed tests there is a little bit of traffic crossing, but they were all done within minutes of each other so there is no bursty traffic that could be skewing this). When both interfaces are up we regularly are seeing 1.3Mbit down and 2.8-3.0Mbit up. There are no physical layer issues on the T1 controllers (no code violations, slip seconds, errored seconds). There are no input/output errors on the multilink virtual interface, no drops, etc. Sprint verifies seeing similar results on their interfaces.
Has anyone ever seen this before? Any idea what could be causing such an issue.
The config of the serial and multilink interface are: (ip address changed)
interface Multilink1
ip address 1.2.3.4 255.255.255.252
ip nbar protocol-discovery
ip nat outside
load-interval 30
ppp multilink
ppp multilink interleave
ppp multilink group 1
ppp multilink multiclass
max-reserved-bandwidth 100
!
interface Serial0/2/0:0
no ip address
ip nbar protocol-discovery
encapsulation ppp
no fair-queue
ppp multilink
ppp multilink group 1
max-reserved-bandwidth 100
!
interface Serial0/2/1:0
no ip address
ip nbar protocol-discovery
encapsulation ppp
no fair-queue
ppp multilink
ppp multilink group 1
max-reserved-bandwidth 100
show ppp multilink (with the above config):
Multilink1, bundle name is sl-gw14-fw
Endpoint discriminator is sl-gw14-fw
Bundle up for 01:48:10, total bandwidth 3072, load 1/255
Receive buffer limit 24000 bytes, frag timeout 1000 ms
Interleaving disabled
0/0 fragments/bytes in reassembly list
90 lost fragments, 5073 reordered
0/0 discarded fragments/bytes, 0 lost received
0xC0A80 received sequence, 0x882F3 sent sequence
Member links: 2 active, 0 inactive (max not set, min not set)
Se0/2/0:0, since 01:48:10, 5760 weight, 1496 frag size
Se0/2/1:0, since 01:00:08, 5760 weight, 1496 frag size
No inactive multilink interfaces
NOTE: The ppp multilink interleave command was removed and the same symptoms occur, however show ppp multilink shows:
Multilink1, bundle name is sl-gw14-fw
Endpoint discriminator is sl-gw14-fw
Bundle up for 01:49:06, total bandwidth 3072, load 1/255
Receive buffer limit 24000 bytes, frag timeout 1000 ms
0/0 fragments/bytes in reassembly list
90 lost fragments, 5073 reordered
0/0 discarded fragments/bytes, 0 lost received
0xC0D91 received sequence, 0x88632 sent sequence
Member links: 2 active, 0 inactive (max not set, min not set)
Se0/2/0:0, since 01:49:06
Se0/2/1:0, since 01:01:04
No inactive multilink interfaces
also ppp multilink multiclass was removed with the same symptoms
'ppp multilink fragment disable' was added to the config with the same symptoms.
ideas? thanks in advance!
ray
