Clock Rate issue 2

[zaradell]

Good afternoon to you all

I´m having a problem setting my DCE router´s clock rate. I have a Cisco 1841 with IOS c1841-ipbase-mz.123-14.T5.bin.

I have another router working as DTE connected to my serial 0/1/0. I´m trying to establish a clock rate of 1,5Mbps (1536000) and for some reason it doesn´t work. I´m able to establish a clock rate of 256000 and 512000 but that´s all.
Any other clock rate value and my serial 0/1/0 goes up/down.

Here´s my interface configuration:

interface Serial0/1/0
ip address 192.168.190.129 255.255.255.248
ip nat inside
encapsulation ppp
load-interval 30
clockrate 256000

Any suggestions?

Thkx

 

[burtsbees]

try clock rate 4000000
It can't go past 1.5 anyway. Also, post sh int s0/1/0

Burt

 

[zaradell]

burtsbees, I´ve tried setting the clock to 4000000 but no luck. Here´s the show int serial 0/1/0:

Serial0/1/0 is up, line protocol is up
Hardware is GT96K Serial
Description: Ligacao serie a router da CMS - SMAS
Internet address is 192.168.190.129/29
MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,
reliability 255/255, txload 19/255, rxload 2/255
Encapsulation PPP, LCP Open
Open: CDPCP, IPCP, loopback not set
Keepalive set (10 sec)
Last input 00:00:11, output 00:00:16, output hang never
Last clearing of "show interface" counters 21:06:21
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 1055
Queueing strategy: weighted fair
Output queue: 1/1000/64/1055 (size/max total/threshold/drops)
Conversations 1/46/256 (active/max active/max total)
Reserved Conversations 0/0 (allocated/max allocated)
Available Bandwidth 1158 kilobits/sec
30 second input rate 18000 bits/sec, 25 packets/sec
30 second output rate 119000 bits/sec, 25 packets/sec
745451 packets input, 52752237 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
759633 packets output, 507045899 bytes, 0 underruns
0 output errors, 0 collisions, 5 interface resets
0 output buffer failures, 0 output buffers swapped out
2 carrier transitions
DCD=up DSR=up DTR=up RTS=up CTS=up

 

[burtsbees]

Available Bandwidth 1158 kilobits/sec
This maybe tells me that this is all this WIC can do...5 interface resets means that it reset because there was too much going at it, and it had to drop what was in the queue buffer (overflow), because it can't handle the load...interesting thing to research...I'll get back later...

Burt

 

[zaradell]

Burt

Any feedback?

 

[Minue]

Hello
Is this a Lab setup?What's the model of the router acting as the DTE?Try to make this router the DCE and use the T1 clock rate or E1 (clock rate 2000000).
Regards

 

[zaradell]

Minue

This is no lab. I´m trying to set up one of our routers with a client´s router. I don´t know the model of it´s equipment.

And unfortunately I cannot set up the client´s router as the DCE since I´m working for the ISP.

 

[burtsbees]

First off, does the line protocol go down immediately when you go above 512000? Have you tried any other values between 512000 and 1536000, like
768000
800000
1000000
1300000
?
What is the other router? Can you post a sh run of the interface of the other router, along with sh int and sh controllers? Please post a sh controllers s0/1/0 of the 1841 as well.

Burt

 

[zaradell]

Burt

As soon as I define a clock rate above 512000 I loose communication: it´s instant.

As for the client´s router, it´s a Cisco 3640 and the serial configuration connected to our router is very simple:

interface Serial3/0
ip address 192.168.190.131 255.255.255.248
encapsulation ppp

I cannot post a show controllers, since I have no access to the client´s router, but I have confirmed with the client that the interfaces are defined has DTE.

 

[Viconsul]

Zaradell

You have stated that the setup is not in a lab, if so, then the telco providing the link will naturally be providing the clockrate, which seems to be set to 1544kbit from the int Serial0/1/0 status you posted. That is effectively the 1.5 Mbps you are paying for.

In a lab environment when you have the routers connected back to back with a cross serial cable, then you would need to set the clock rate on either of the two routers which is designated as the DCE node.

You can however control the bandwidth used on the link with the bandwidth command on the serial interface.

HTH
-Viconsul

 

[burtsbees]

Not only that, but if it is a csu/dsu (T1), the clock may be on the line or internal, not like an asynchronous link, like you are testing...

Burt

 

[zaradell]

The connection is simple: 2 routers, one DCE (with clock rate defined) and the other DTE with the configurarion that I have posted:

interface Serial3/0
ip address 192.168.190.131 255.255.255.248
encapsulation ppp

I´ve tried to set the bandwith command to "bandwidth 1536" but with no luck. I cannot get a clock rate above 512000 and I`m not able to get traffic above 512000 to my client´s router.

Since my ISP bandwith on serial 0/0/0 is 1,5 Mbit, as you might imagine this is not a very good situation.

 

[zaradell]

Here´s the configuration of my router. Maybe you can find something wrong that I´m missing:

Current configuration : 5989 bytes
!
version 12.3
service timestamps debug datetime msec
service timestamps log datetime localtime
service password-encryption
!
hostname XXXDS
!
boot-start-marker
boot-end-marker
!
logging buffered 51200 warnings
!
no aaa new-model
!
resource policy
!
clock timezone GMT 0
clock summer-time GMT recurring last Sun Mar 1:00 last Sun Oct 2:00
mmi polling-interval 60
no mmi auto-configure
no mmi pvc
mmi snmp-timeout 180
ip subnet-zero
ip cef
!
!
no ip dhcp use vrf connected
!
!
no ip domain lookup
no ftp-server write-enable
!
username XXXX privilege 15 secret 5 $1$8c5U$zJ3pP.
username XXXX privilege 10 password 7 1307B72
username XXXX privilege 15 secret 5 $1$Uw8wRjMf1
!
!
!
interface Loopback0
ip address 172.XX.XX.XXX 255.255.255.255
ip rip advertise 10
!
interface Loopback110
ip address 172.XX.XX.XXX 255.255.255.255
!
interface Loopback111
ip address 172.XX.XX.XXX 255.255.255.255
!
interface FastEthernet0/0
no ip address
shutdown
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
shutdown
duplex auto
speed auto
!
interface Serial0/0/0
description connected to MPLS
bandwidth 1536
no ip address
encapsulation frame-relay
logging event subif-link-status
logging event dlci-status-change
load-interval 30
no fair-queue
frame-relay lmi-type cisco
!
interface Serial0/0/0.100 point-to-point
bandwidth 1536
ip address 10.XX.XX.XXX 255.255.255.252
ip nat outside
ip rip advertise 10
frame-relay interface-dlci 100
!
interface Serial0/1/0
description Connected to client
ip address 192.168.190.129 255.255.255.248
ip nat inside
encapsulation ppp
load-interval 30
clockrate 256000
!
router rip
version 2
timers basic 10 15 15 31
redistribute connected
network 10.0.0.0
distribute-list aclrip2mpls out Serial0/0/0.100
no auto-summary
!
ip classless
ip route 134.XX.XX.XXX 255.255.0.0 Serial0/1/0
ip route 135.XX.XX.XXX 255.255.0.0 Serial0/1/0
ip route 136.XX.XX.XXX 255.255.0.0 Serial0/1/0
ip route 137.XX.XX.XXX 255.255.0.0 Serial0/1/0
ip route 138.XX.XX.XXX 255.255.0.0 Serial0/1/0
ip route 139.XX.XX.XXX 255.255.0.0 Serial0/1/0
!
no ip http server
ip nat inside source list 110 interface Loopback110 overload
ip nat inside source static 136.XX.XX.XXX interface Loopback111
!
ip access-list standard aclrip2mpls
deny 0.0.0.0
deny 192.168.190.128 0.0.0.7
permit any
!
ip access-list extended Inter-traffic
permit ip any 172.XX.XX.XXX 0.0.0.31
permit ip any 172.XX.XX.XXX 0.0.0.255
permit ip any 172.XX.XX.XXX 0.0.0.31
permit ip any 10.2XX.XX.XXX 0.0.0.7
permit ip any host 172.XX.XX.XXX
!
logging trap warnings
logging source-interface Loopback0
logging 172.XX.XX.XXX
logging 172.XX.XX.XXX
logging 172.XX.XX.XXX
access-list 16 permit 10.XX.XX.XXX
access-list 16 permit 10.XX.XX.XXX 0.0.0.7
access-list 16 permit 172.XX.XX.XXX 0.0.0.31
access-list 16 permit 172.XX.XX.XXX 0.0.0.31
access-list 16 permit 172.XX.XX.XXX 0.0.0.255
access-list 16 permit 172.XX.XX.XXX 0.0.0.31
access-list 20 permit 10.XX.XX.XXX 0.0.0.31
access-list 20 permit 172.XX.XX.XXX 0.0.0.255
access-list 20 permit 172.XX.XX.XXX 0.0.0.255
access-list 20 permit 172.XX.XX.XXX 0.0.0.31
access-list 20 permit 10.XX.XX.XXX 0.0.255.255
access-list 20 permit 195.XX.XX.XXX 0.0.0.63
access-list 20 permit 195.XX.XX.XXX 0.0.0.127
access-list 20 permit 172.XX.XX.XXX 0.0.255.255
access-list 20 permit 172.XX.XX.XXX 0.0.0.255
access-list 20 permit 10.XX.XX.XXX 0.0.0.15
access-list 110 deny ip host 136.XX.XX.XXX any
access-list 110 permit ip any host 172.XX.XX.XXX
access-list 110 permit ip any host 172.XX.XX.XXX
access-list 110 permit ip any host 172.XX.XX.XXX
access-list 110 permit ip any host 172.XX.XX.XXX
access-list 110 permit ip any 193.XX.XX.XXX 0.0.1.255
access-list 110 permit ip any 193.XX.XX.XXX 0.0.0.255
access-list 110 permit ip any 172.XX.XX.XXX 0.0.0.255
snmp-server community XXXXXXX RO 16
snmp-server trap-source Loopback0
!
control-plane
!
banner motd ^CC
*************************************************************************

ONI TELECOM

*************************************************************************

UNAUTHORISED ACCESS IS PROHIBITED


*************************************************************************
^C
privilege exec level 10 traceroute
privilege exec level 10 ping
privilege exec level 10 show diag
privilege exec level 10 show startup-config
privilege exec level 0 show
!
line con 0
privilege level 15
password 7 045804081C4
login
stopbits 1
line aux 0
line vty 0 4
access-class 20 in
login local
!
ntp clock-period 17179696
ntp update-calendar
ntp server 172.XX.XX.XXX prefer
ntp server 172.XX.XX.XXX prefer
end

 

[burtsbees]

Well, I am still kind of unsure of your setup...any way the client can be DCE and you be the DTE?

Burt

 

[zaradell]

Burt

That´s not a possible option. I work for the ISP, is our job to control and limit the bandwith and clock rate available to the client...as such our equipment has got to take the role of the DCE router: we cannot alow the client to become DCE: he has to be DTE.

I really don´t get why this is happening...the Serial configurations on both routers are very straightforward. I really don´t understand why with higher clock rates I´m not able to communicate with my client´s router.

 

[Minue]

Hello
A lot of us have never seen such a setup.Do you care to explain how this setup is possible.Is the customer router in the same building as Cisco 1841,what kind of cabling are you using.
Most dedicated lines will have 2 DCE's that handles the clocking and the interface conversion.V35,V24 etc. and the normal phone that cross the WAN.Please explain we are all baffled.
Regards

 

[zaradell]

Ok, I´ll try and explain.

I work for the ISP providing MPLS service to the client. However the client itself has a router that connects to it´s lan.

My router simply works as a "bridge" between the client´s router and the MPLS cloud.

So basically it works like this: my 1841 Cisco router connects to the MPLS cloud through my Serial 0/0/0 (with a bandwith of 1,5Mbps), and then it routes all traffic to my client´s router connected through Serial0/1/0. The 1841 and 3640 (client´s router) are back to back, in the same building.

As routing goes, all is well: the traffic is going where needs to be going. The only problem, is that I cannot define a clock rate above 512000 between my router, and the client´s router through Serial0/1/0.

And I know what your next question is going to be: "If you simply have 2 routers connected in the same building, why did you use a Serial Connection instead of a RJ45 LAN Connection?" ...and the answer is, I have no idea why!The transmission team defined that this connection had to be Serial, and now I´m suposed to clean their mess =)

Anyway, I can´t change the structure of the connection, and I have to guarantee the most bandwith available to the client...in this case the 1,5 Mbps of the MPLS service...for that I have to establish a clock rate between the 2 routers of 1536000, and for some reason I cannot establish a clock rate above 512000.

I hope I made this more clear to you.
Does anybody know of any issues configuring clock rates between 1841 and 3640 routers?

 

[Minue]

Hello
Thanks so much for the explanation.Now things are much clearer now.
The next troubleshooting step would be to try a differert IOS release.Also if you have the possibility to access the customer router.Try to shutdown the interface before changing the clock rate.
Regards

 

[zaradell]

My IOS is c1841-ipbase-mz.123-14.T5.bin.

Does anybody know of a more apropriate one?

 

[Minue]

Hello
Try this site and search for a plus or enterprise version.

http://tools.cisco.com/ITDIT/CFN/jsp/index.jsp

Regards