How do you troubleshoot Ethernet?

kevin.hu · ‎05-27-2010

Currently we have an OC-12 Packet Over Sonet link from one 6506 to another 6506 across the country. The provider offered us to use GigE access option to their Cisco ONS MSPP to bring down monthly recurring cost .

My question is, how do you do loopback test/troubleshoot Ethernet type of network across SONET? If the provider give you a loop from their network, are you able to see it? Also, can Ethernet OAM be configured on 6506 Sup720 to perform end to end Ethernet montoring in case the provider's network is having problem?

Ganesh Hariharan · ‎06-14-2010

Currently we have an OC-12 Packet Over Sonet link from one 6506 to another 6506 across the country. The provider offered us to use GigE access option to their Cisco ONS MSPP to bring down monthly recurring cost .

My question is, how do you do loopback test/troubleshoot Ethernet type of network across SONET? If the provider give you a loop from their network, are you able to see it? Also, can Ethernet OAM be configured on 6506 Sup720 to perform end to end Ethernet montoring in case the provider's network is having problem?

Hi,

Check out the below link for loopback test in cisco devices

http://www.cisco.com/en/US/tech/tk713/tk628/technologies_tech_note09186a00800a754b.shtml

Hope to Help !!

Ganesh.H

If helpful do rate the post

kevin.hu · ‎06-14-2010

No, this link is for serial loopback. I am talking about Ethernet service. How do you do Ethernet loopback from my building or from provider's network?

judebryant · ‎07-19-2010

First of all you cannot loopback ethernet. Its connectionless oriented. The service provider can loop the TDM part but thats it.

You might try IP Sla's between your two devices. With this you can measure jitter, delay, and latency. Im not sure if the boxes you are using witll support CFM, you might look into that.

Regards

Jude Bryant

Network Engineer

Pioneer Telephone

kevin.hu · ‎07-19-2010

Jude,

Since then I have found my answer. Actually there are two end-to-end Ethernet OAM standards, IEEE 802.1ag and 802.1ah. However, I am not sure if it is already incorporated in 12.4T code or not.

In addition to 802.1ag or 802.1ah, I can also use Bidirectional Forwarding Detection (BFD) to detect end-to-end failure as BFD is layer 2 independent.

Kevin

judebryant · ‎07-19-2010

Kevin,

Yes the 802.1ag falls under the CFM. however 802.1ah PBB is for VPLS. This is the MacINMac standard. Not sure you can do this with the equipment you have.

The Bidirectional Forwarding Detection seems like a great options. I am not familiar with it, however just read some information on it, and will be configuring this in my test lab for additional familiarity.

Regards

Jude

reevesfernandes · ‎03-10-2011

Hi there,

Once the link is reported down by you to the ISP they perform certain checks

ISP will -

1)Check the BGP status, the output will show them that the link is down and which end it is down.

2)If fault still existing with no known alarms in their network the only option is "End to End” test. This refers to a process where sets of field engineers are sent to two different locations, usually end or demarcation points on a network, to physically attach testers to prove section of it 100% clean.

On Ethernet services there is no BERT or loop pinging ability.