02-20-2007 04:54 AM - edited 03-17-2019 08:57 PM
Hi,
We have 4 sites connected via ATM and pass VoIP across it.
Each site has a break out point for PSTN over E1s.
We are getting calls routed out the network, presumably due to network congestion.
Our ATM is at about 10% utilisation, so I am assuming it is not the problem.
How can I check on the routers / in Callmanager to find out how many calls are being passed over the ATM and at what point they should be sent outside.
Thanks,
Roy
02-20-2007 05:25 AM
One initial approach is to check if you have packet loss on the ATM network. To do that,
issue "clear counters" on all the routers at the same time. I know you can't do exactly do that at the same time, but just try to make it closer as possible, by using multiple terminals or PCs.
Let the network run one day or two, then check output of "show atm pvc". Your in/out counters should match almost exactly on the corresponding router pairs.
This said, one should look at how your router are configured and what could be triggering the CCM to route off-net.
02-20-2007 05:31 AM
We do get the following from Ciscoworks, but my predecessor said he was told to ignore them as it's a Ciscoworks thing not an actual problem ...
Now I'm thinking it's maybe not Ciscoworks !
EVENT ID = 0003S6C
ALERT ID = 000021Z
TIME = Tue 20-Feb-2007 09:48:45 GMT
STATUS = Active
SEVERITY = Critical
MANAGED OBJECT = hostname
MANAGED OBJECT TYPE = Routers
EVENT DESCRIPTION = HighQueueDropRate::Component=IF-hostname/1
[AT1/0] [###Cct Ref
xxxxxxxxxx###];Type=DS3;OutputPacketNoErrorRate=553.2792
PPS;DuplexMode=FULLDUPLEX;InputPacketQueueDropRate=0.0
PPS;InputPacketQueueDropPct=0.0
%;MaxSpeed=34000000;OutputPacketQueueDropPct=1.0182385
%;OutputPacketQueueDropRate=5.6916666
PPS;QueueDropThreshold=1;InputPacketNoErrorRate=522.8125
02-20-2007 06:27 AM
Put Ciscoworks on the side for a moment. Log into the router and check the output of "show interface" and "show atm pvc". This will definitely tell you if there is packet drops.
If there is, you can configure QoS to prioritize traffic.
02-20-2007 06:57 AM
Look OK to me (though that does not count for much !)
4 sites as follows ....
Site 1
VCD / Peak Avg/Min Burst
Interface Name VPI VCI Type Encaps SC Kbps Kbps Cells Sts
1/0.1 ip 1 32 PVC SNAP VBR 23041 23041 1 UP
ATM1/0.1 is up, line protocol is up
Hardware is RS8234 ATM E3
Description: Link to WAN
Interface is unnumbered. Using address of Loopback0 (172.16.32.1)
MTU 4470 bytes, BW 15380 Kbit, DLY 200 usec,
reliability 255/255, txload 27/255, rxload 4/255
Encapsulation ATM
3693063238 packets input, 836279283496 bytes
4234968585 packets output, 2985021406173 bytes
1242098 OAM cells input, 1242059 OAM cells output
AAL5 CRC errors : 2
AAL5 SAR Timeouts : 0
AAL5 Oversized SDUs : 0
AAL5 length violation : 2
AAL5 CPI Error : 0
Last clearing of "show interface" counters never
Site 2
VCD / Peak Avg/Min Burst
Interface Name VPI VCI Type Encaps SC Kbps Kbps Cells Sts
1/0.1 ip 1 32 PVC SNAP VBR 12289 12289 1 UP
ATM1/0.1 is up, line protocol is up
Hardware is RS8234 ATM E3
Description: IPenabled PVC
Interface is unnumbered. Using address of Loopback0 (172.16.96.1)
MTU 4470 bytes, BW 8192 Kbit, DLY 200 usec,
reliability 255/255, txload 6/255, rxload 25/255
Encapsulation ATM
65698888 packets input, 48152269948 bytes
51070492 packets output, 8186070871 bytes
25607 OAM cells input, 25607 OAM cells output
AAL5 CRC errors : 0
AAL5 SAR Timeouts : 0
AAL5 Oversized SDUs : 0
AAL5 length violation : 0
AAL5 CPI Error : 0
Last clearing of "show interface" counters never
Site 3
VCD / Peak Avg/Min Burst
Interface Name VPI VCI Type Encaps SC Kbps Kbps Cells Sts
1/0.1 1 1 32 PVC SNAP VBR 12289 12289 1 UP
ATM1/0.1 is up, line protocol is up
Hardware is RS8234 ATM E3
Description: Link to WAN
Interface is unnumbered. Using address of Loopback0 (172.16.64.1)
MTU 4470 bytes, BW 8192 Kbit, DLY 200 usec,
reliability 255/255, txload 4/255, rxload 8/255
Encapsulation ATM
2461584158 packets input, 1901335110529 bytes
2109706319 packets output, 510523746062 bytes
1416854 OAM cells input, 1416844 OAM cells output
AAL5 CRC errors : 0
AAL5 SAR Timeouts : 0
AAL5 Oversized SDUs : 0
AAL5 length violation : 0
AAL5 CPI Error : 0
Last clearing of "show interface" counters never
Site 4
VCD / Peak Avg/Min Burst
Interface Name VPI VCI Type Encaps SC Kbps Kbps Cells Sts
1/0.1 1 1 32 PVC SNAP VBR 3072 3072 1 UP
CRTC01CO#
ATM1/0.1 is up, line protocol is up
Hardware is RS8234 ATM E3
Description: Link to WAN
Interface is unnumbered. Using address of Loopback0 (172.16.128.1)
MTU 4470 bytes, BW 2048 Kbit, DLY 200 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ATM
852613330 packets input, 214858179060 bytes
862469522 packets output, 226533712205 bytes
5233929 OAM cells input, 5233904 OAM cells output
AAL5 CRC errors : 0
AAL5 SAR Timeouts : 0
AAL5 Oversized SDUs : 0
AAL5 length violation : 0
AAL5 CPI Error : 0
Last clearing of "show interface" counters never
02-20-2007 08:54 AM
Which platform is that? IOS used?
Please check output of show interface for the main interface. Any drop, as well queueing strategy is indicated there.
02-20-2007 12:44 PM
Will do, not in work tomorrow, so will post findings on Thursday.
Thanks,
Roy
02-22-2007 03:51 AM
How's this look to you ?
Total output drops don't look to be a huge percentage .
First two -
sh int atm 1/0
ATM1/0 is up, line protocol is up
Hardware is RS8234 ATM E3
MTU 4470 bytes, sub MTU 4470, BW 34000 Kbit, DLY 200 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ATM, loopback not set
Encapsulation(s): AAL5
1023 maximum active VCs, 1 current VCCs
VC Auto Creation Disabled.
VC idle disconnect time: 300 seconds
Last input 00:00:00, output 00:00:00, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 5657
Queueing strategy: Per VC Queueing
5 minute input rate 36000 bits/sec, 15 packets/sec
5 minute output rate 20000 bits/sec, 14 packets/sec
855333609 packets input, 885989034 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
865260006 packets output, 3580294569 bytes, 0 underruns
0 output errors, 0 collisions, 3 interface resets
0 output buffer failures, 0 output buffers swapped out
sh int atm 1/0
ATM1/0 is up, line protocol is up
Hardware is RS8234 ATM E3
MTU 4470 bytes, sub MTU 4470, BW 34000 Kbit, DLY 200 usec,
reliability 255/255, txload 1/255, rxload 3/255
Encapsulation ATM, loopback not set
Encapsulation(s): AAL5
1023 maximum active VCs, 1 current VCCs
VC Auto Creation Disabled.
VC idle disconnect time: 300 seconds
Last input 00:00:00, output 00:00:00, output hang never
Last clearing of "show interface" counters 23w5d
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 159544
Queueing strategy: Per VC Queueing
5 minute input rate 413000 bits/sec, 150 packets/sec
5 minute output rate 188000 bits/sec, 159 packets/sec
2484602076 packets input, 4076778704 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
2130796755 packets output, 3173954929 bytes, 0 underruns
0 output errors, 0 collisions, 2 interface resets
0 output buffer failures, 0 output buffers swapped out
02-22-2007 03:52 AM
Second two -
sh int atm 1/0
ATM1/0 is up, line protocol is up
Hardware is RS8234 ATM E3
Description: ###Cct Ref xxxxxxx ###
MTU 4470 bytes, sub MTU 4470, BW 34000 Kbit, DLY 200 usec,
reliability 255/255, txload 14/255, rxload 9/255
Encapsulation ATM, loopback not set
Encapsulation(s): AAL5
1023 maximum active VCs, 1 current VCCs
VC Auto Creation Disabled.
VC idle disconnect time: 300 seconds
Last input 00:00:00, output 00:00:00, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 6245796
Queueing strategy: Per VC Queueing
5 minute input rate 1309000 bits/sec, 520 packets/sec
5 minute output rate 1936000 bits/sec, 555 packets/sec
3742088962 packets input, 4139908101 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 1 throttles
0 input errors, 2 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
1939101 packets output, 3830119708 bytes, 0 underruns
0 output errors, 0 collisions, 4 interface resets
0 output buffer failures, 0 output buffers swapped out
sh int atm 1/0
ATM1/0 is up, line protocol is up
Hardware is RS8234 ATM E3
Description: ###Cct Ref IEUK###
MTU 4470 bytes, sub MTU 4470, BW 34000 Kbit, DLY 200 usec,
reliability 255/255, txload 10/255, rxload 11/255
Encapsulation ATM, loopback not set
Encapsulation(s): AAL5
1023 maximum active VCs, 1 current VCCs
VC Auto Creation Disabled.
VC idle disconnect time: 300 seconds
Last input 00:00:10, output 00:00:00, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 2401
Queueing strategy: Per VC Queueing
5 minute input rate 1519000 bits/sec, 448 packets/sec
5 minute output rate 1373000 bits/sec, 424 packets/sec
113135448 packets input, 330360174 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
87565722 packets output, 2195499762 bytes, 0 underruns
0 output errors, 0 collisions, 1 interface resets
0 output buffer failures, 0 output buffers swapped out
02-23-2007 07:38 PM
Right, the drop ratio is not large and beside you have per-VC queuing, supposedly based on LLQ for media traffic, but we haven't seen that piece of your config yet. Probably just a matter of fine tuning to get the best from what is basically sane already.
02-26-2007 12:34 AM
One thing I have noticed in our configs -
3 sites have an interface level bandwidth statment reflecting 34Mb - then the sub-interface reflects the actual speed.
However 1 site has no interface level statment, just the correct speed on the sub-interface.
I do not believe this is a problem, but any thoughts would be appreciated.
Thanks,
Roy
02-26-2007 07:43 AM
Hi Roy,
In cisco IOS the "bandwidth" stetmente is merely informative and does not affect the way router handles traffic. In case of ATM, it's VC traffic parameters and per-VC queuing that counts.
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