03-23-2010 11:58 AM - edited 03-06-2019 10:16 AM
hi,
My name is Serge DIAI and i'm a head manager in technical support in a company in morroco.
One of our activities is based on voip.
In our infrastructure we have our own switch catalyst 2950 and router cisco 1812 managed by the FAI.
On the catalyst we haved switched 2 server IPBX ASTERISK ,A voip gateway (QUINTUM) and the router CISCO.
I want to configure qos of voip at the catalyst interface (F0/23) wich is connected to the router cisco or in general in the catalyst to give preferential treatment to voip traffic to resolve some problem when congestion occurs.
Is that possible?
Can you help me
Thank you for your attention
03-23-2010 12:50 PM
This page should help you get started.
03-23-2010 12:55 PM
To add to Glens post (great link BTW), are you sure there is contention on the link between the router and the switch? I would double check speed and duplex and make sure they match and that there are no errors on the interfaces.
03-24-2010 05:41 AM
Thanks for your response.
To answer to glan, i have already seen the link and read this chapter.
But I don't know for my case what model i have to choose. (voip traffic using SIP, H323 and IAX protocol on my LAN) and I dont use cisco ip phone but softphone such as pangolin, eyebeam.
And to answer to collin., i want to do this because 1st we use the same Link WAN on the router for voip and data.
So sometimes we have some noise or some "hatching" (don't know if it's the good term in english) likes robot voice.
And in this case when I check the catalyst interface connected on the router in general I don't see errors on CRC but bandwich used in input and output is high.
For example:
CATALYST2950#show ip traffic
IP statistics:
Rcvd: 12807967 total, 2622166 local destination
0 format errors, 0 checksum errors, 0 bad hop count
0 unknown protocol, 10185801 not a gateway
0 security failures, 0 bad options, 22986 with options
Opts: 0 end, 0 nop, 0 basic security, 0 loose source route
0 timestamp, 0 extended security, 0 record route
0 stream ID, 0 strict source route, 22986 alert, 0 cipso
0 other
Frags: 0 reassembled, 0 timeouts, 0 couldn't reassemble
0 fragmented, 0 couldn't fragment
Bcast: 2591021 received, 3 sent
Mcast: 0 received, 0 sent
Sent: 111960 generated, 0 forwarded
Drop: 1595 encapsulation failed, 0 unresolved, 0 no adjacency
0 no route, 0 unicast RPF, 0 forced drop
Drop: 0 packets with source IP address zero
ICMP statistics:
Rcvd: 0 format errors, 0 checksum errors, 0 redirects, 1 unreachable
3274 echo, 0 echo reply, 0 mask requests, 0 mask replies, 0 quench
0 parameter, 0 timestamp, 0 info request, 0 other
0 irdp solicitations, 0 irdp advertisements
Sent: 0 redirects, 0 unreachable, 0 echo, 3274 echo reply
0 mask requests, 0 mask replies, 0 quench, 0 timestamp
0 info reply, 0 time exceeded, 0 parameter problem
0 irdp solicitations, 0 irdp advertisements
UDP statistics:
Rcvd: 2591129 total, 0 checksum errors, 2591129 no port
Sent: 82636 total, 0 forwarded broadcasts
TCP statistics:
Rcvd: 27873 total, 0 checksum errors, 0 no port
Sent: 26054 total
ARP statistics:
Rcvd: 13742785 requests, 1975 replies, 0 reverse, 0 other
Sent: 5217 requests, 8860 replies (0 proxy), 0 reverse
CATALYST2950#sh int f0/23
FastEthernet0/23 is up, line protocol is up (connected)
Hardware is Fast Ethernet, address is 0014.6a44.1817 (bia 0014.6a44.1817)
MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,
reliability 255/255, txload 3/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 100Mb/s, media type is 100BaseTX
input flow-control is unsupported output flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:29, 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: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 542000 bits/sec, 864 packets/sec
5 minute output rate 1429000 bits/sec, 1994 packets/sec
892958707 packets input, 426096684 bytes, 0 no buffer
Received 85795 broadcasts (0 multicast)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 84702 multicast, 0 pause input
0 input packets with dribble condition detected
1952507841 packets output, 640219550 bytes, 0 underruns
0 output errors, 0 collisions, 2 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier, 0 PAUSE output
0 output buffer failures, 0 output buffers swapped out
03-24-2010 06:22 AM
I'm pretty sure those are accumulated numbers. Under the interface you can see the load-
txload 3/255, rxload 1/255
poor mans way of calculating-
3/255*100=1.2% utilization
1/255*100=0.4% utilization
To implement QoS, the link that Glen provided should provide a good framework. You may have to mark the traffic as it come into the switch, it depends if your applications already mark their traffic. Another good QoS reference is the SRND-
http://www.cisco.com/en/US/docs/solutions/Enterprise/WAN_and_MAN/QoS_SRND/QoSDesign.html
Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community: