Rogers cable Internet w/ Cisco 2611

[dreamaz]

Hi,

i use rogers cable (Motorola DOCSIS modem) ffor internet connected to my E0/1 interface on my 2611. Does anyone know whether my E0/1 should be configured as Full-Duplex or Half?, when i have it as full i get numerous errors, interface resets and slow bandwidth. On half i get better speed, less errors but still not the 7mbps+ i should be getting.

When connected directly from pc to cable modem, i get 8mbps

Thanks,

Sameer

 

[octavian10]

Cable modems communicate at 10mbs Half Duplex, so set your int to half duplex. As for your bandwith the 8 mbs is what it is capable of, this does not mean that you will ever see this speed. Remember that with cable modems you literally share bandwith with TV so during American Idol for example you will not be even close to 8mbs.

"I hear and I forget. I see and I remember. I do and I understand."
- Confucius (551 BC - 479)

 

[Knackster]

Remember that with cable modems you literally share bandwith with TV so during American Idol for example you will not be even close to 8mbs.

THat's not quite correct. Cable modem traffic, in its most simplistic terms, is channelised just as regular tv channels are. The number of TV viewers period have absolutely no bearing on cable modem bandwidth. Remember, just think of a TV channel as broadcast traffic sent to all itnerfaces ( tv set top boxes) It hits the end user regardless if they are watching a particular channel or even have your TV on.

Now, if the cable modem box is docsis 2.0 compliant, I believe that it is a 100 meg full interface. Easiest way to test is to hook your pc straight up and see what it negotiates at.

 

[burtsbees]

I don't think posting a sh int e0/1 and a sh run at this point could hurt...

Burt

 

[dreamaz]

Thanks for the replies..

I understand about cable modem sharing BW etc, its just that when i plug the cable modem directly to my PC i get the 8mbps, when i put my router in tehre i get 1.5mbps. And this problem just started, i was getting 7mbps through this cisco router before.

I've pasted my config below: (i added the buffer config hoping that will help but it didn't)

Current configuration : 2247 bytes
!
version 12.3
service timestamps debug datetime msec
service timestamps log datetime msec
service password-encryption
!
hostname tmn
!
boot-start-marker
boot-end-marker
!
logging buffered 64000 warnings
enable secret 5 ********************
enable password 7 ****************
!
clock timezone EST -5
no aaa new-model
ip subnet-zero
ip cef
!
!
ip audit po max-events 100
!
!
buffers small permanent 150
buffers small max-free 230
buffers small min-free 50
buffers middle permanent 70
buffers middle max-free 120
buffers middle min-free 50
buffers huge permanent 2
!
!
!
interface Ethernet0/0
no ip address
ip nat inside
full-duplex
!
interface Ethernet0/0.1
encapsulation dot1Q 10
ip address 10.1.1.65 255.255.255.192
ip nat inside
no cdp enable
!
interface Ethernet0/0.2
encapsulation dot1Q 11
ip address 10.1.1.129 255.255.255.192
ip nat inside
no cdp enable
!
interface Serial0/0
no ip address
shutdown
!
interface Ethernet0/1
ip address dhcp
ip nat outside
half-duplex
no cdp enable
!
interface Serial0/1
no ip address
shutdown
!
ip nat inside source list NAT interface Ethernet0/1 overload
ip http server
no ip http secure-server
ip classless
!
!
ip access-list extended NAT
permit ip 10.1.1.0 0.0.0.255 any
logging history errors
!
!
!
!
!
!
line con 0
line aux 0
line vty 0 4
password 7 XXXXXXXXXXXXXXXX
login
line vty 5
password 7 XXXXXXXXXXXXXXXX
login
!
!
end

---------------------------------

sh int e0/1
Ethernet0/1 is up, line protocol is up
Hardware is AmdP2, address is 0008.21d1.88c1
Internet address is **.***.***.***/**
MTU 1500 bytes, BW 10000 Kbit, DLY 1000 usec,
reliability 255/255, txload 1/255, rxload 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 00:00:02, output hang never
Last clearing of "show interface" counters 2d23h
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 1000 bits/sec, 1 packets/sec
5 minute output rate 1000 bits/sec, 1 packets/sec
636584 packets input, 322219785 bytes, 0 no buffer
Received 357152 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 input packets with dribble condition detected
254097 packets output, 45156759 bytes, 0 underruns
0 output errors, 607 collisions, 1 interface resets
0 babbles, 0 late collision, 1844 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
=============================
sh contr e0/1
Interface Ethernet0/1
Hardware is AMD Presidio
ADDR: 82C0C758, FASTSEND: 800245B4, MCI_INDEX: 0
DIST ROUTE ENABLED: 0
Route Cache Flag: 11
LADRF=0x0000 0x0000 0x0000 0x0000
CSR0 =0x00000072, CSR3 =0x00001044, CSR4 =0x0000491D, CSR15 =0x00000000
CSR80 =0x0000D900, CSR114=0x00000000, CRDA =0x03D3E1C0, CXDA =0x03D3E3E0
BCR9 =0x00000000 (half-duplex)
HW filtering information:
Promiscuous Mode Disabled, PHY Addr Enabled, Broadcast Addr Enabled
PHY Addr=000E.A6CD.B59A, Multicast Filter=0x0000 0x0000 0x0000 0x0000
amdp2_instance=0x82C0DF00, registers=0x40100000, ib=0x3D3E060
rx ring entries=32, tx ring entries=64
rxring=0x3D3E0C0, rxr shadow=0x82C0E174, rx_head=16, rx_tail=0
txring=0x3D3E300, txr shadow=0x82C0E220, tx_head=14, tx_tail=14, tx_count=0
Software MAC address filter(hash:length/addr/mask/hits):
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=50496, tx_more_col_err=110866, tx_no_enp=0, tx_deferred_err=466525
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
hsrp_conf=0, need_af_check=0
tx_limited=0(64)

==============================

Any help is appreciated.

Thanks

 

[burtsbees]

Have you tried without vlans configured? Also, perhaps try looking at mtu...

Burt

 

[dreamaz]

I removed my 2950 sw connected to e0/0 on the router, used a x-over cable and plugged my pc straight to the router's e0/0 port, no change

u think its a problem with my the e0/0 interface connected to my lan and not the e0/1 int connected to the cable modem?

 

[burtsbees]

I don't think so...I'm kinda stumped like you are. However, I have found that after spending a certain amount of time trying to troubleshoot, I just save the current config and start all over with a very simple config, slowly adding extra non-default parts(like all the buffers) rather than working backwards and removing things out of the config. Start with saving the current config, then console to the router (if you don't already do) and put in a very simple e0/0 ip address and no shut config with nat, and slowly start adding everything else you have that is non-default, like buffers, etc. In the "show int e0/1" output, I see these lines...
5 minute input rate 1000 bits/sec, 1 packets/sec
5 minute output rate 1000 bits/sec, 1 packets/sec
If you choose to start over with a fresh config, please post back and let us know what you find...this I think is the best approach if it has been working for a while, but suddenly stopped working. Seems that something has changed with the cable company, according to what you have posted. I would also put an ip address and nat statements for e0/1, in case it turns out to be the module itself, or the deal that houses both ethernet interfaces. If it has been working before, and it suddenly stops, and nobody has made any configuration changes on the cable company's end or your end, this points to hardware. I would also see if you can't temporarily acquire another router to try and confirm this. Please post back, and may the force be with you, and good luck, and all that...

Burt

 

[yemaya]

Hi.

I got roger cable for more than 2 years, i got the faster opcion they have(6mb) for residential and i never in 2 years got more than 3mb, i live very close to roger building and i'm telling you, was very sad pay around $60 bucks for 6mb and only got 3mb or less and after 5pm to 11 pm got less that 2mb, i'm not telling you that you have the same problem that i had before but could be the problem.

Hope this help.