Cisco 2600 series

[datadan]

I have 4 cisco routers in my network with 2 point to point connections to remote offices.

I have noticed over the years that I get quite a bit of collisions when I use the show interfaces command on the ethernet ports.

What tools are available to me within the cisco router to trouble shoot the source of these problems.

Router 1: e/card 1: 10.10.10.10 255.255.0.0
e/card 2: 10.10.12.254 255.255.255.0
Router 2: 10.11.10.10 255.255.0.0
Router 3: 10.10.12.2 255.255.255.0
Router 4: 10.60.40.1 255.255.0.0

Router 3 & 1 are in the same physical location.
Router 4 connects to router 3 via point to point
Router 2 connects to router 1 via point to point

Any feed back will be appreciated.

Thanks,

 

[Andyleates]

check that the speed and duplex settings match on the routers ethernet port and whatever it connects to (switch or whatever) at the other end.

Andy Leates MCSE CCNA MCP+I

 

[mtashiro]

Andyleates is correct, check speed and duplex. If it's a half duplex connection then you will have collisions.

 

[datadan]

I have several settings on my switches:

Auto Negotiation = Enabled (for all switches)
Speed/Duplex = Auto (for all switches)
Full Duplex Flow Control = Auto (for all switches)
Half Duplex Flow Control = Enabled (for all switches)

It seems to me like I need to disable half duplex flow control --or-- change my router config. How can I tell what speed/duplex my routers are configured for?



Thanks

 

[IllegalOperation]

"How can I tell what speed/duplex my routers are configured for?"

show running config
show interfaces
show interface (serial x, ethernet x, etc)

 

[datadan]

Here are some configs --> However it does not tell net whether or not it is full or half duplex, nor what speed it is running (100mbs or 10mbs) -->? Thanks

interface Ethernet0/0
ip address 10.10.10.10 255.255.255.0
ip nat inside
no ip mroute-cache
ipx network BBB100
ipx type-20-propagation
no mop enabled

interface Ethernet0/1
description dmz
ip address 10.10.12.254 255.255.255.0
no ip mroute-cache

interface FastEthernet0/0
ip address 10.10.12.2 255.255.255.0
no ip redirects
no ip directed-broadcast
ip route-cache policy
no ip mroute-cache
ip policy route-map genname
ipx network BBB100
no ipx route-cache
ipx type-20-propagation

 

[mtashiro]

The interfaces that say Ethernet0/0 and Ethernet 0/1 are 10M only. The one that says FastEthernet0/1 can be either 10M or 100M.

Type show interface and it will show you the interfaces and the speed and duplex they are running.

 

[datadan]

Thanks mtashiro

Here is my interface, but I don't see duplex or speed mentioned anywhere? Is the the default then full duplex 10mbs?

My FastEthernet router states 100mbs and full duplex so I will be changing the switch configuration to turn off half duplex flow enabled, but I will leave Speed/Duplex set to Auto and Full Duplex Flow Control to Auto.


Ethernet0/0 is up, line protocol is up
Hardware is AmdP2, address is 0010.7bd3.bb40 (bia 0010.7bd3.bb40)
Internet address is 10.10.10.10/24
MTU 1500 bytes, BW 10000 Kbit, DLY 1000 usec, rely 254/255, load 1/255
Encapsulation ARPA, loopback not set, keepalive set (10 sec)
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:01, output 00:00:00, output hang never
Last clearing of "show interface" counters never
Queueing strategy: fifo
Output queue 0/40, 0 drops; input queue 0/75, 0 drops
5 minute input rate 5000 bits/sec, 11 packets/sec
5 minute output rate 5000 bits/sec, 10 packets/sec
1738483 packets input, 157863599 bytes, 0 no buffer
Received 135332 broadcasts, 0 runts, 0 giants, 0 throttles
164814 input errors, 0 CRC, 0 frame, 0 overrun, 164814 ignored, 0 abort
0 input packets with dribble condition detected
1244647 packets output, 167209333 bytes, 0 underruns
0 output errors, 34401 collisions, 2 interface resets
0 babbles, 0 late collision, 10274 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out



Ethernet0/1 is up, line protocol is up
Hardware is AmdP2, address is 0010.7bd3.bb41 (bia 0010.7bd3.bb41)
Description: dmz
Internet address is 10.10.12.254/24
MTU 1500 bytes, BW 10000 Kbit, DLY 1000 usec, rely 255/255, load 1/255
Encapsulation ARPA, loopback not set, keepalive set (10 sec)
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:00, output 00:00:00, output hang never
Last clearing of "show interface" counters never
Queueing strategy: fifo
Output queue 0/40, 25 drops; input queue 0/75, 0 drops
5 minute input rate 5000 bits/sec, 6 packets/sec
5 minute output rate 3000 bits/sec, 4 packets/sec
937180 packets input, 160609806 bytes, 0 no buffer
Received 143184 broadcasts, 0 runts, 0 giants, 0 throttles
12 input errors, 0 CRC, 0 frame, 0 overrun, 12 ignored, 0 abort
0 input packets with dribble condition detected
1060865 packets output, 85961558 bytes, 0 underruns
0 output errors, 19221 collisions, 2 interface resets
0 babbles, 0 late collision, 2997 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out

 

[mtashiro]

Most likely since it is a 10M interface and you see collisions it's running at half duplex.

You can try changing the duple but not all IOS versions support 10M Full duplex. Change the switch port to.

 

[IllegalOperation]

First off, "show interface" is the same thing as "show interfaces".

Second, is there a full-duplex 10mbps? Never knew that was possible. If those interfaces were full-duplex, you wouldnt be getting so many collisions.

Third, ethernet0/0 is reporting 164,814 input errors...which is not good at all. What are you connecting to that interface? Check the cable, and replace it if possible.

Fourth, if this is an issue regarding the duplex and speed negotiaton of your interfaces - you need to administratively set the parameters for every interface that is involved....regardless of what you think it is currently configured for. In other words, just go to each interface you think is having problems negotiating (or is not matched up correctly), and manually enter the speed and duplex.

 

[IllegalOperation]

Sorry to add again, but this just popped in my head. Do a "show controller ethernet 0/0", and let us know how many multiple collisions and excessive collisions it is reporting on that interface.


It is hard to determine if you have "too many" collisions, because we do not know how long your counters have been running. Clear your counters (AFTER you do the show controller command), and then take another reading five or so minutes later.

 

[datadan]

IllegalOperation -- Thanks,

<snip>
In other words, just go to each interface you think is having problems negotiating (or is not matched up correctly), and manually enter the speed and duplex.
</snip>
to accomplish this would I for each non-Fast Ethernet connection:
config t
int e 0/0
half-duplex
cntl Z
wr mem

Also below the counters were cleared yesterday morning. So this is 24 hours of activity. Both routers plug into the same 3com 3300 12 port switch.

Interface Ethernet0/0
Hardware is AMD Presidio2
ADDR: 80DE92B0, FASTSEND: 80022A28, MCI_INDEX: 0
DIST ROUTE ENABLED: 0
Route Cache Flag: 1
LADRF=0x0000 0x0100 0x0008 0x0000
CSR0 =0x00000072, CSR3 =0x00001044, CSR4 =0x00004B1D, CSR15 =0x80F8743C
CSR80 =0x0000D900, CSR114=0x00000000, CRDA =0x018F6050, CXDA =0x018F6190
HW filtering information:
Promiscuous Mode Disabled, PHY Addr Enabled, Broadcast Addr Enabled
PHY Addr=0010.7BD3.BB40, Multicast Filter=0x0000 0x0100 0x0008 0x0000
amdp2_instance=0x80DEAA60, registers=0x40000000, ib=0x18F5E60
rx ring entries=32, tx ring entries=64
rxring=0x18F5EC0, rxr shadow=0x80DEAC24, rx_head=25, rx_tail=0
txring=0x18F6100, txr shadow=0x80DEACD0, tx_head=9, tx_tail=9, tx_count=0
spurious_idon=0, throttled=0, enabled=0, disabled=0
rx_framing_err=0, rx_overflow_err=0, rx_buffer_err=0
rx_bpe_err=0, rx_soft_overflow_err=0, rx_no_enp=0, rx_discard=0
tx_one_col_err=9468, tx_more_col_err=26294, tx_no_enp=0, tx_deferred_err=10681
tx_underrun_err=0, tx_late_collision_err=0, tx_loss_carrier_err=0
tx_exc_collision_err=0, tx_buff_err=0, fatal_tx_err=0


InnerstepCorporate#show controllers ethernet 0/1
Interface Ethernet0/1
Hardware is AMD Presidio2
ADDR: 80DEC228, FASTSEND: 80022A28, MCI_INDEX: 0
DIST ROUTE ENABLED: 0
Route Cache Flag: 1
LADRF=0x0000 0x0100 0x0008 0x0000
CSR0 =0x00000072, CSR3 =0x00001044, CSR4 =0x0000491D, CSR15 =0x80F8743C
CSR80 =0x0000D900, CSR114=0x00000000, CRDA =0x0191CA10, CXDA =0x0191CF40
HW filtering information:
Promiscuous Mode Disabled, PHY Addr Enabled, Broadcast Addr Enabled
PHY Addr=0010.7BD3.BB41, Multicast Filter=0x0000 0x0100 0x0008 0x0000
amdp2_instance=0x80DED9D8, registers=0x40100000, ib=0x191C980
rx ring entries=32, tx ring entries=64
rxring=0x191C9E0, rxr shadow=0x80DEDB9C, rx_head=3, rx_tail=0
txring=0x191CC20, txr shadow=0x80DEDC48, tx_head=50, tx_tail=50, tx_count=0
spurious_idon=0, throttled=0, enabled=0, disabled=0
rx_framing_err=0, rx_overflow_err=0, rx_buffer_err=0
rx_bpe_err=0, rx_soft_overflow_err=0, rx_no_enp=0, rx_discard=0
tx_one_col_err=10983, tx_more_col_err=8520, tx_no_enp=0, tx_deferred_err=3085
tx_underrun_err=0, tx_late_collision_err=0, tx_loss_carrier_err=0
tx_exc_collision_err=0, tx_buff_err=0, fatal_tx_err=0

 

[IllegalOperation]

Well you dont have to worry about your router interfaces, as they cant do any better than 10/half. On your switch however, configure the interfaces your two routers are connected on to force 10/half....

config t
int F x/x
speed 10
duplex half
cntl Z
wr mem


Also, you are reporting multiple collisions (frames that collide more than once) but no excessive collisions (frames that reached the max amount of collisions allowed). Multiple collisions can be fairly common, but excessive collisions indicate a critical problem (bad NIC cards, overloaded traffic, etc). Collisions are normal occurances in an ethernet environment....and generally multiply as traffic on the medium is increased. This can simply be a matter of high load on your ethernet network. Collisions commonly increase over periods of time, as you add additional devices to the network.

However, your first router's input error rate is excessive. Like I said, replace the cable (if possible) going from your ethernet 0/0 interface on your router to the switch....and make sure both devices are communicating at 10mbps/half duplex. If you are still reporting a high count of input errors, you might have an interface that is going bad....

 

[datadan]

Thanks for all the help. My first router is not a fast ethernet and is not accepting the speed 10 / duplex half. I am therefore assuming that router by defaut runs at speed 10 and duplex half.

I will try the cable. Interestingly, my FastEthernet router has no collisions while my older routers seem to have more.

aside from the following settings on my FastEthernet router:
process-max-time 200
memory-size iomem 10
ip subnet-zero
ip domain-name

the settings appear to be the same.
The IOS version of FasterEthernet = 12.0 while the other routers are at 11.3.

Could any of these difference contribute to the problem?

 

[IllegalOperation]

No. There are no collisions with FastEthernet. Only Ethernet utilizes CSMA/CD.

If you see any collisions on two linking interfaces that are set for 100/full - then you need to go to the Ripley's Believe It Or Not website and post there.

 

[IllegalOperation]

datadan, did replacing the cable have any effect?

 

[datadan]

Switching cable did not appear to help. After switching the cable and restarting the router I am still getting a high amount of collisions and input errors.

Are there any other tools/software I can use that can help me diagnose where these are comming from?

Thanks,


Ethernet0/0 is up, line protocol is up
Hardware is AmdP2, address is 0010.7bd3.bb40 (bia 0010.7bd3.bb40)
Internet address is 10.10.10.10/24
MTU 1500 bytes, BW 10000 Kbit, DLY 1000 usec, rely 252/255, load 1/255
Encapsulation ARPA, loopback not set, keepalive set (10 sec)
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:00, output 00:00:00, output hang never
Last clearing of &quot;show interface&quot; counters never
Queueing strategy: fifo
Output queue 0/40, 0 drops; input queue 0/75, 0 drops
5 minute input rate 11000 bits/sec, 21 packets/sec
5 minute output rate 8000 bits/sec, 14 packets/sec
1054223 packets input, 127774989 bytes, 0 no buffer
Received 308177 broadcasts, 0 runts, 0 giants, 0 throttles
93218 input errors, 0 CRC, 0 frame, 0 overrun, 93218 ignored, 0 abort
0 input packets with dribble condition detected
738737 packets output, 73605608 bytes, 0 underruns
0 output errors, 12750 collisions, 2 interface resets
0 babbles, 0 late collision, 4755 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out

 

[IllegalOperation]

How long is the distance between this router and the switch? The problem could be too much noise (outside interference) on this link. Are you using a standard four-pair ethernet CAT5 cable to connect these two interfaces? Do you see any kinks in the cable or any other physical damage?

Assuming your interfaces are configured correctly, this looks to be a hardware problem. You need to isolate and identify this problem. Are you seeing any of these errors on the switch's interface? If it is possible, try moving your router to a different interface on the switch....or at least swapping interfaces with the other router. Swap out anything that can be either involved or at least a factor with this problem. Make sure your IOS is at the latest version. The final test should be to see what would happen if you replace the router all together (assuming you have a spare or a way of obtaining one). Is this device still under warranty? Ive seen Cisco routers and switches with bad interfaces plenty of times. It could simply be a hardware problem inside the router. I would start looking into your device replacement options.

Take a look at this guide, as it might be of some help...

http://www.cisco.com/en/US/tech/tk389/tk214/technologies_tech_note09186a008009446d.shtml