Solved: Timeouts on Multilink?

Mark Lind · ‎11-21-2013

Hello,

I have an older 2811 router running 'c2800nm-advipservicesk9-mz.124-10.bin' in Mexico. Two VWIC2-1MFT-G703 cards are installed for the E1 lines (2Mbt) and combined into a multilink. Getting output drops on the multilink but the serial lines are clean. Odd thing is, I get dropped packets when pinging the multilink. CPU Proc is 7%. QOS is enabled/running.

I have a Cisco TAC case open for the output drops.

Really curious as to how the multilink can fail pings with low proc?

Thanks

John Blakley · ‎11-21-2013

I'm not sure where icmp falls in the mix of your class-maps, so it's hard for me to tell if it's getting classified or dumped into the default queue. I don't see any errors on the interfaces/links at all, so I doubt this is a carrier issue. Are there any other issues that you've noticed outside of losing a packet or two from a ping?

HTH,
John

*** Please rate all useful posts ***

HTH, John *** Please rate all useful posts ***

View solution in original post

John Blakley · ‎11-21-2013

Did this just start? Output drops are normal if you're running qos on the interface:

Multilink1 is up, line protocol is up

Hardware is multilink group interface

MTU 1500 bytes, BW 3072 Kbit/sec, DLY 20000 usec,

reliability 255/255, txload 30/255, rxload 54/255

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 2w6d

Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 35505

Queueing strategy: Class-based queueing

Output queue: 0/1000/0/94660 (size/max total/drops/interleaves)

Can you post the config of the multilink interface and the two serials?

HTH,
John

*** Please rate all useful posts ***

HTH, John *** Please rate all useful posts ***

Mark Lind · ‎11-21-2013

Slowly came to my attention as a Oracle DB app that is time delay sensitive started disconnects and then complaints.

interface Multilink1

bandwidth 4098

ip address 10.19.191.65 255.255.255.252

no cdp enable

ppp multilink

ppp multilink links minimum 1

ppp multilink group 1

max-reserved-bandwidth 100

service-policy output EGRESS_QUEUING_TO_

interface Serial0/0/0:0
bandwidth 2048
no ip address
no ip redirects
no ip unreachables
no ip proxy-arp
encapsulation ppp
ppp multilink
ppp multilink group 1
max-reserved-bandwidth 100

interface Serial0/1/0:0
bandwidth 2048
no ip address
no ip redirects
no ip unreachables
no ip proxy-arp
encapsulation ppp
ppp multilink
ppp multilink group 1
max-reserved-bandwidth 100

sh int mu1

Multilink1 is up, line protocol is up

Hardware is multilink group interface

Internet address is 10.19.191.65/30

MTU 1500 bytes, BW 4098 Kbit, DLY 100000 usec,

reliability 255/255, txload 12/255, rxload 17/255

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 01:35:47

Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 1608

Queueing strategy: Class-based queueing

Output queue: 1/1000/64/1608 (size/max total/threshold/drops)

Conversations 1/3/256 (active/max active/max total)

Reserved Conversations 4/4 (allocated/max allocated)

Available Bandwidth 3482 kilobits/sec

5 minute input rate 275000 bits/sec, 52 packets/sec

5 minute output rate 195000 bits/sec, 48 packets/sec

632772 packets input, 487272157 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

519285 packets output, 181449630 bytes, 0 underruns

0 output errors, 0 collisions, 2 interface resets

0 output buffer failures, 0 output buffers swapped out

0 carrier transitions

ping 10.19.191.65 rep 1000 siz 1000

Type escape sequence to abort.
Sending 1000, 1000-byte ICMP Echos to 10.19.191.65, timeout is 2 seconds:
!!!!!!!!!!!!!!!!!!!!!!!.!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!.!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!
Success rate is 99 percent (998/1000), round-trip min/avg/max = 24/26/136 ms

sh int mu1

John Blakley · ‎11-21-2013

Can you also post "show int s0/0/0:0" and "show int s0/1/0:0"?

HTH,
John

*** Please rate all useful posts ***

HTH, John *** Please rate all useful posts ***

Mark Lind · ‎11-21-2013

sh int Serial0/0/0:0

Serial0/0/0:0 is up, line protocol is up

Hardware is GT96K Serial

MTU 1500 bytes, BW 2048 Kbit, DLY 20000 usec,

reliability 255/255, txload 12/255, rxload 33/255

Encapsulation PPP, LCP Open, multilink Open

Link is a member of Multilink bundle Multilink1, loopback not set

Keepalive set (10 sec)

Last input 00:00:00, output 00:00:00, output hang never

Last clearing of "show interface" counters 01:48:58

Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0

Queueing strategy: weighted fair [suspended, using FIFO]

FIFO output queue 0/40, 0 drops

5 minute input rate 268000 bits/sec, 43 packets/sec

5 minute output rate 99000 bits/sec, 49 packets/sec

351267 packets input, 266818227 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

385063 packets output, 102263244 bytes, 0 underruns

0 output errors, 0 collisions, 1 interface resets

0 output buffer failures, 0 output buffers swapped out

0 carrier transitions

Timeslot(s) Used: UNFRAMED, SCC: 0, Transmitter delay is 0 flags

sh int Serial0/1/0:0

Serial0/1/0:0 is up, line protocol is up

Hardware is GT96K Serial

MTU 1500 bytes, BW 2048 Kbit, DLY 20000 usec,

reliability 255/255, txload 12/255, rxload 32/255

Encapsulation PPP, LCP Open, multilink Open

Link is a member of Multilink bundle Multilink1, loopback not set

Keepalive set (10 sec)

Last input 00:00:00, output 00:00:00, output hang never

Last clearing of "show interface" counters 01:49:03

Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0

Queueing strategy: weighted fair [suspended, using FIFO]

FIFO output queue 0/40, 0 drops

5 minute input rate 262000 bits/sec, 42 packets/sec

5 minute output rate 97000 bits/sec, 48 packets/sec

350977 packets input, 267035026 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

380241 packets output, 101338105 bytes, 0 underruns

0 output errors, 0 collisions, 1 interface resets

0 output buffer failures, 0 output buffers swapped out

0 carrier transitions

Timeslot(s) Used: UNFRAMED, SCC: 0, Transmitter delay is 0 flags

John Blakley · ‎11-21-2013

I don't see any problems with the interfaces. Can you post "show controllers e1"?

Actually, can you post your policy-map for QoS? Have you tried taking this policy off to see if it's causing a problem? Are there other problems other than pinging your local interface?

HTH,
John

*** Please rate all useful posts ***

HTH, John *** Please rate all useful posts ***

Mark Lind · ‎11-21-2013

sh controller e1

E1 0/0/0 is up.

Applique type is Channelized E1 - unbalanced

No alarms detected.

alarm-trigger is not set

Version info Firmware: 20060711, FPGA: 13, spm_count = 0

Framing is UNFRAMED, Line Code is HDB3, Clock Source is Line.

CRC Threshold is 320. Reported from firmware is 320.

Data in current interval (675 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

Total Data (last 7 15 minute intervals):

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

sh policy-map int mu1
Multilink1

Service-policy output: EGRESS_QUEUING_TO_ATT

    Class-map: NMC (match-any)
      0 packets, 0 bytes
      5 minute offered rate 0 bps, drop rate 0 bps
      Match: access-group 178
        0 packets, 0 bytes
        5 minute rate 0 bps
      Match: access-group 180
        0 packets, 0 bytes
        5 minute rate 0 bps
      Queueing
        Output Queue: Conversation 265
        Bandwidth remaining 2 (%)
        (pkts matched/bytes matched) 0/0
        (depth/total drops/no-buffer drops) 0/0/0
         exponential weight: 9
         mean queue depth: 0

   dscp    Transmitted      Random drop      Tail drop    Minimum Maximum Mark
           pkts/bytes       pkts/bytes       pkts/bytes    thresh thresh prob
   af11       0/0               0/0              0/0           32      40 1/10
   af12       0/0               0/0              0/0           28      40 1/10
   af13       0/0               0/0              0/0           24      40 1/10
   af21       0/0               0/0              0/0          200     300 1/10
   af22       0/0               0/0              0/0           28      40 1/10
   af23       0/0               0/0              0/0           24      40 1/10
   af31       0/0               0/0              0/0           32      40 1/10
   af32       0/0               0/0              0/0           28      40 1/10
   af33       0/0               0/0              0/0           24      40 1/10
   af41       0/0               0/0              0/0           32      40 1/10
   af42       0/0               0/0              0/0           28      40 1/10
   af43       0/0               0/0              0/0           24      40 1/10
    cs1       0/0               0/0              0/0           22      40 1/10
    cs2       0/0               0/0              0/0           24      40 1/10
    cs3       0/0               0/0              0/0           26      40 1/10
    cs4       0/0               0/0              0/0           28      40 1/10
    cs5       0/0               0/0              0/0           30      40 1/10
    cs6       0/0               0/0              0/0          200     300 1/10
    cs7       0/0               0/0              0/0           34      40 1/10
     ef       0/0               0/0              0/0           36      40 1/10
   rsvp       0/0               0/0              0/0           36      40 1/10
default       0/0               0/0              0/0           20      40 1/10

Service-policy : NMC_CLASSIFICATION

        Class-map: NMC_RP (match-all)
          0 packets, 0 bytes
          5 minute offered rate 0 bps, drop rate 0 bps
          Match: access-group 178
          police:
              cir 16000 bps, bc 8000 bytes
            conformed 0 packets, 0 bytes; actions:
              set-dscp-transmit cs6
            exceeded 0 packets, 0 bytes; actions:
              set-dscp-transmit cs6
            conformed 0 bps, exceed 0 bps

        Class-map: NMC_SNMP (match-all)
          0 packets, 0 bytes
          5 minute offered rate 0 bps, drop rate 0 bps
          Match: access-group 180
          police:
              cir 16000 bps, bc 8000 bytes
            conformed 0 packets, 0 bytes; actions:
              set-dscp-transmit af21
            exceeded 0 packets, 0 bytes; actions:
              set-dscp-transmit af21
            conformed 0 bps, exceed 0 bps

        Class-map: class-default (match-any)
          0 packets, 0 bytes
          5 minute offered rate 0 bps, drop rate 0 bps
          Match: any

    Class-map: COS1 (match-any)
      0 packets, 0 bytes
      5 minute offered rate 0 bps, drop rate 0 bps
      Match: class-map match-all COS1_SAA
        0 packets, 0 bytes
        5 minute rate 0 bps
        Match: ip dscp ef (46)
        Match: access-group 179
      Match: class-map match-all COS1_TRAFFIC
        0 packets, 0 bytes
        5 minute rate 0 bps
        Match: access-group name ATT-COS1
      Queueing
        Strict Priority
        Output Queue: Conversation 264
        Bandwidth 616 (kbps) Burst 15400 (Bytes)
        (pkts matched/bytes matched) 0/0
        (total drops/bytes drops) 0/0

Service-policy : COS1_CLASSIFICATION

        Class-map: COS1_TRAFFIC (match-all)
          0 packets, 0 bytes
          5 minute offered rate 0 bps, drop rate 0 bps
          Match: access-group name ATT-COS1
          police:
              cir 616000 bps, bc 77000 bytes
            conformed 0 packets, 0 bytes; actions:
              set-dscp-transmit ef
            exceeded 0 packets, 0 bytes; actions:
              drop
            conformed 0 bps, exceed 0 bps

        Class-map: class-default (match-any)
          0 packets, 0 bytes
          5 minute offered rate 0 bps, drop rate 0 bps
          Match: any

    Class-map: COS2 (match-any)
      9813 packets, 530483 bytes
      5 minute offered rate 0 bps, drop rate 0 bps
      Match: class-map match-all COS2_SAA
        0 packets, 0 bytes
        5 minute rate 0 bps
        Match: ip dscp af31 (26)
        Match: access-group 179
      Match: class-map match-all COS2_TRAFFIC
        9813 packets, 530483 bytes
        5 minute rate 0 bps
        Match: access-group name ATT-COS2
      Queueing
        Output Queue: Conversation 266
        Bandwidth remaining 59 (%)
        (pkts matched/bytes matched) 378/20498
        (depth/total drops/no-buffer drops) 0/0/0
         exponential weight: 1
         mean queue depth: 0

   dscp    Transmitted      Random drop      Tail drop    Minimum Maximum Mark
           pkts/bytes       pkts/bytes       pkts/bytes    thresh thresh prob
   af11       0/0               0/0              0/0           32      40 1/10
   af12       0/0               0/0              0/0           28      40 1/10
   af13       0/0               0/0              0/0           24      40 1/10
   af21       0/0               0/0              0/0           32      40 1/10
   af22       0/0               0/0              0/0           28      40 1/10
   af23       0/0               0/0              0/0           24      40 1/10
   af31    9813/530483          0/0              0/0          200     300 1/10
   af32       0/0               0/0              0/0           28      40 1/10
   af33       0/0               0/0              0/0           24      40 1/10
   af41       0/0               0/0              0/0           32      40 1/10
   af42       0/0               0/0              0/0           28      40 1/10
   af43       0/0               0/0              0/0           24      40 1/10
    cs1       0/0               0/0              0/0           22      40 1/10
    cs2       0/0               0/0              0/0           24      40 1/10
    cs3       0/0               0/0              0/0           26      40 1/10
    cs4       0/0               0/0              0/0           28      40 1/10
    cs5       0/0               0/0              0/0           30      40 1/10
    cs6       0/0               0/0              0/0           32      40 1/10
    cs7       0/0               0/0              0/0           34      40 1/10
     ef       0/0               0/0              0/0           36      40 1/10
   rsvp       0/0               0/0              0/0           36      40 1/10
default       0/0               0/0              0/0           20      40 1/10

Service-policy : COS2_CLASSIFICATION

        Class-map: COS2_TRAFFIC (match-all)
          9813 packets, 530483 bytes
          5 minute offered rate 0 bps, drop rate 0 bps
          Match: access-group name ATT-COS2
          police:
              cir 552000 bps, bc 69000 bytes
            conformed 9813 packets, 530483 bytes; actions:
              set-dscp-transmit af31
            exceeded 0 packets, 0 bytes; actions:
              set-dscp-transmit af32
            conformed 0 bps, exceed 0 bps

        Class-map: class-default (match-any)
          0 packets, 0 bytes
          5 minute offered rate 0 bps, drop rate 0 bps
          Match: any

    Class-map: COS3 (match-any)
      0 packets, 0 bytes
      5 minute offered rate 0 bps, drop rate 0 bps
      Match: class-map match-all COS3_SAA
        0 packets, 0 bytes
        5 minute rate 0 bps
        Match: ip dscp af21 (18)
        Match: access-group 179
      Match: class-map match-all COS3_TRAFFIC
        0 packets, 0 bytes
        5 minute rate 0 bps
        Match: access-group name ATT-COS3
      Queueing
        Output Queue: Conversation 267
        Bandwidth remaining 30 (%)
        (pkts matched/bytes matched) 0/0
        (depth/total drops/no-buffer drops) 0/0/0
         exponential weight: 1
         mean queue depth: 0

   dscp    Transmitted      Random drop      Tail drop    Minimum Maximum Mark
           pkts/bytes       pkts/bytes       pkts/bytes    thresh thresh prob
   af11       0/0               0/0              0/0           32      40 1/10
   af12       0/0               0/0              0/0           28      40 1/10
   af13       0/0               0/0              0/0           24      40 1/10
   af21       0/0               0/0              0/0          200     300 1/10
   af22       0/0               0/0              0/0           28      40 1/10
   af23       0/0               0/0              0/0           24      40 1/10
   af31       0/0               0/0              0/0           32      40 1/10
   af32       0/0               0/0              0/0           28      40 1/10
   af33       0/0               0/0              0/0           24      40 1/10
   af41       0/0               0/0              0/0           32      40 1/10
   af42       0/0               0/0              0/0           28      40 1/10
   af43       0/0               0/0              0/0           24      40 1/10
    cs1       0/0               0/0              0/0           22      40 1/10
    cs2       0/0               0/0              0/0           24      40 1/10
    cs3       0/0               0/0              0/0           26      40 1/10
    cs4       0/0               0/0              0/0           28      40 1/10
    cs5       0/0               0/0              0/0           30      40 1/10
    cs6       0/0               0/0              0/0           32      40 1/10
    cs7       0/0               0/0              0/0           34      40 1/10
     ef       0/0               0/0              0/0           36      40 1/10
   rsvp       0/0               0/0              0/0           36      40 1/10
default       0/0               0/0              0/0           20      40 1/10

Service-policy : COS3_CLASSIFICATION

        Class-map: COS3_TRAFFIC (match-all)
          0 packets, 0 bytes
          5 minute offered rate 0 bps, drop rate 0 bps
          Match: access-group name ATT-COS3
          police:
              cir 280000 bps, bc 35000 bytes
            conformed 0 packets, 0 bytes; actions:
              set-dscp-transmit af21
            exceeded 0 packets, 0 bytes; actions:
              set-dscp-transmit af22
            conformed 0 bps, exceed 0 bps

        Class-map: class-default (match-any)
          0 packets, 0 bytes
          5 minute offered rate 0 bps, drop rate 0 bps
          Match: any

    Class-map: COS4 (match-any)
      604993 packets, 212393151 bytes
      5 minute offered rate 170000 bps, drop rate 0 bps
      Match: class-map match-all COS4_SAA
        0 packets, 0 bytes
        5 minute rate 0 bps
        Match: ip dscp default (0)
        Match: access-group 179
      Match: class-map match-all COS4_TRAFFIC
        604993 packets, 212393151 bytes
        5 minute rate 170000 bps
        Match: access-group name ATT-COS4
      Queueing
        Output Queue: Conversation 268
        Bandwidth remaining 8 (%)
        (pkts matched/bytes matched) 129144/116955885
        (depth/total drops/no-buffer drops) 0/1860/0
         exponential weight: 1
         mean queue depth: 0

   dscp    Transmitted      Random drop      Tail drop    Minimum Maximum Mark
           pkts/bytes       pkts/bytes       pkts/bytes    thresh thresh prob
   af11       0/0               0/0              0/0           32      40 1/10
   af12       0/0               0/0              0/0           28      40 1/10
   af13       0/0               0/0              0/0           24      40 1/10
   af21       0/0               0/0              0/0           32      40 1/10
   af22       0/0               0/0              0/0           28      40 1/10
   af23       0/0               0/0              0/0           24      40 1/10
   af31       0/0               0/0              0/0           32      40 1/10
   af32       0/0               0/0              0/0           28      40 1/10
   af33       0/0               0/0              0/0           24      40 1/10
   af41       0/0               0/0              0/0           32      40 1/10
   af42       0/0               0/0              0/0           28      40 1/10
   af43       0/0               0/0              0/0           24      40 1/10
    cs1       0/0               0/0              0/0           22      40 1/10
    cs2       0/0               0/0              0/0           24      40 1/10
    cs3       0/0               0/0              0/0           26      40 1/10
    cs4       0/0               0/0              0/0           28      40 1/10
    cs5       0/0               0/0              0/0           30      40 1/10
    cs6       0/0               0/0              0/0           32      40 1/10
    cs7       0/0               0/0              0/0           34      40 1/10
     ef       0/0               0/0              0/0           36      40 1/10
   rsvp       0/0               0/0              0/0           36      40 1/10
default 603140/210792251    1843/1600496       17/714         20      40 1/10

Service-policy : COS4_CLASSIFICATION

        Class-map: COS4_TRAFFIC (match-all)
          604993 packets, 212393151 bytes
          5 minute offered rate 170000 bps, drop rate 0 bps
          Match: access-group name ATT-COS4
          police:
              cir 96000 bps, bc 12000 bytes
            conformed 467769 packets, 55669015 bytes; actions:
              set-dscp-transmit default
            exceeded 137231 packets, 156724446 bytes; actions:
              set-dscp-transmit default
            conformed 53000 bps, exceed 124000 bps

        Class-map: class-default (match-any)
          0 packets, 0 bytes
          5 minute offered rate 0 bps, drop rate 0 bps
          Match: any

    Class-map: class-default (match-any)
      746 packets, 4506 bytes
      5 minute offered rate 0 bps, drop rate 0 bps
      Match: any

No I have not. Production location with voip going across as well as Oracle traffic.

John Blakley · ‎11-21-2013

I'm not sure where icmp falls in the mix of your class-maps, so it's hard for me to tell if it's getting classified or dumped into the default queue. I don't see any errors on the interfaces/links at all, so I doubt this is a carrier issue. Are there any other issues that you've noticed outside of losing a packet or two from a ping?

HTH,
John

*** Please rate all useful posts ***

HTH, John *** Please rate all useful posts ***

Mark Lind · ‎11-21-2013

The main problem is the connection back to a Oracle database. Any latency and the connection drops to where end user has to log back into this erp system.

There is a Telnor/Telmex LEC in the middle between us and AT&T providing two CSU/DSUs and, from what I can tell, they are DSL based? They hand off to AT&T then ride our MPLS back.

I might be barking up the wrong tree and these output drops on the MU1 are not even the issue. Just wanted a 3rd pair of eyes on it

I am going to have to review the QOS more in depth.

bbaillie · ‎11-21-2013

Hi Mark,

I see the drops and policing being used in the QOS, without the specifics on where the Oracle traffic resides in the QOS it is hard to locate an issue.

The dropping of pings on the multilink interface is odd, I don't see the use of a password or serial endpoint string on the serial interfaces. You may want to add the unique serial endpoint strings to the serial interfaces themselves, this may stabilize the multilink interface itself. I have had trouble in past with this issue.

The moment I see MPLS I look for MTU issues, some transceivers carriers use do not support jumbs and cause problems, easier to adjust than to locate the dodgy transceiver. Try a few pings with the DF bit set and larger sizes up to the max of 1472 for determining if the MTU is affected by MPLS in the mix. If the MTU is at issue you can use tcp mss adjust, or IP MTU on the multilink interface, set the tcp mss adjust 40 bytes less than the MTU you determine.

Cheers,

Brian