Can someone improve configurations of T1 routers for performance?

[robertcbyrne]

Hello,

We had the Cisco 1720 routers configured by a third party and have never received good performance on the T1.  Can someone examine the attachments and give feedback on how to improve the configurations.  I have minimal networking skills but understand how to access the devices and type commands.

I have attached a simple network drawing and the configuration files from the two routers.

Appreciate all help,

Bob

[paolo bevilacqua]

Please define "good performances" ?

[robertcbyrne]

The performance measurement is somwhat subjective.   The T1 is used for only 2 purposes.  An application which uses Sybase SQL Anywhere 10 as its base and general internet access from the cwe location.  The performance of the application (according to the provider)  is much slower than at other locations with the same T1 type installation.  I do not know how to test the T1 to gain specific information.

The sql application uses only 4 ports to provide this service. These ports can be modified.  Here is the table used.

Bob

Port #	49152	2638	2639	2439
CWE (Consolidated) 49152/2439	Consolidated server must be able to server out to ALL clients on this port.	X	X	Consolidated Mobilink listener must be   able to send and receive to from All Local   Synch Services(server machine) on this port
CWE (Local) 2638	Local servers should be able to talk to Consolidated on this port	All local clients for CWE need to be able to talk   to the Local CWE database on   this port.	X	CWE local synch service(server machine) needs to be   able to talk to consolidated on   this port.
Downtown (Local) 2639	Local servers should be   able to talk to Consolidated on this port	X	All local clients for   Downtown need to be able to talk to the Downtown Local database on this port	Downtown Local synch service(server machine) needs   to be able to talk to consolidated on this port.

[vmiller]

Some Basics.

For each router, logon  and do a show interface serial0

lets see if there are any layer1 or 2 errors there.

Absent that, I would suspect some tuning on the servers might be in order.

[robertcbyrne]

Here are the two router show interface commands.  Meaningless to me I'm afraid.

Serial0 is up, line protocol is up 
  Hardware is PQUICC with Fractional T1 CSU/DSU
  Description: connected to Cisco1720_2
  Internet address is 192.168.254.1/30
  MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec, 
     reliability 255/255, txload 7/255, rxload 5/255
  Encapsulation HDLC, loopback not set
  Keepalive set (10 sec)
  Last input 00:00:00, output 00:00:01, output hang never
  Last clearing of "show interface" counters never
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 107
  Queueing strategy: weighted fair
  Output queue: 0/1000/64/86 (size/max total/threshold/drops) 
     Conversations  0/21/256 (active/max active/max total)
     Reserved Conversations 0/0 (allocated/max allocated)
     Available Bandwidth 1158 kilobits/sec
  5 minute input rate 34000 bits/sec, 2 packets/sec
  5 minute output rate 46000 bits/sec, 1 packets/sec
     96486796 packets input, 122380769 bytes, 0 no buffer
     Received 1065172 broadcasts, 0 runts, 11 giants, 0 throttles
     16294 input errors, 2608 CRC, 9756 frame, 0 overrun, 0 ignored, 3930 abort
     133213566 packets output, 2504953230 bytes, 0 underruns
     0 output errors, 0 collisions, 133 interface resets
     0 output buffer failures, 0 output buffers swapped out
     51 carrier transitions
     DCD=up  DSR=up  DTR=up  RTS=up  CTS=up

Serial0 is up, line protocol is up 
  Hardware is PQUICC with Fractional T1 CSU/DSU
  Description: connected to Cisco1720_1
  Internet address is 192.168.254.2/30
  MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec, 
     reliability 255/255, txload 5/255, rxload 16/255
  Encapsulation HDLC, 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 never
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 245
  Queueing strategy: weighted fair
  Output queue: 0/1000/64/160 (size/max total/threshold/drops) 
     Conversations  0/97/256 (active/max active/max total)
     Reserved Conversations 0/0 (allocated/max allocated)
  5 minute input rate 99000 bits/sec, 26 packets/sec
  5 minute output rate 36000 bits/sec, 25 packets/sec
     133264370 packets input, 2530474032 bytes, 0 no buffer
     Received 1065563 broadcasts, 0 runts, 7 giants, 0 throttles
     504199 input errors, 80127 CRC, 333126 frame, 0 overrun, 0 ignored, 90941 abort
     96534545 packets output, 129989213 bytes, 0 underruns
     0 output errors, 0 collisions, 133 interface resets
     0 output buffer failures, 0 output buffers swapped out
     67 carrier transitions
     DCD=up  DSR=up  DTR=up  RTS=up  CTS=up

[paolo bevilacqua]

You have way too many errors on the circuit, try a different clocking configure otherwise declare it faulty with telcom, to which they will say it's not, in that case just stop making payments.

[vmiller]

In addition to calling out your provider, pick a time (on the hour) and do a "clear counters" on all affected devices.

the following day at the same time you did the clear, do another show. this will give you a very rough indication of

the rate at which CRC's etc are being incurred.

[robertcbyrne]

Thanks vmiller for your help.  I reset counters, determined that something was continuously broadcasting, then used Wireshark to look at the packets and determined that the every one of the Avaya ip phones were broadcasting a 120byte packet to 239.192.228.123, UDP with source port: blackjack (1025) destination port powerschool (5071), every second or so.   I put a block in the router to stop the traffic from the T1 and performance immediately improved.

Now all I need to do is figure out what's making the phones do thiis.  Anybody seen this?

Thanks for the help,

[vmiller]

Glad to help. note the port names they seem suspicious.

See If avaya has any ideas.