According to Cisco Systems the error “socket SO_UDPCHECKSUM option setting failed error” has no negative impact on the Cisco Catalyst 6500 series Switch. The work around is to remove IP SLA configuration or upgrade the IOS version.

This error appeared for the first time in the IOS version 12.2(33)SXI1 and this bug is fixed in following IOS versions

12.2(32.8.11)SX291
12.2(32.8.11)XJC273.11
12.2(33.2.4)SXI
12.2(32.8.1)YCA273.15
12.2(33)SXI3
12.2(32.8.15)YCA273.10
12.2(33)SXI4
15.0(1)SY

So if you happen to see the following error in your Cisco Catalyst 6500 Series switch don’t panic, the bug has least impact on device the only work around is either to remove the IP SLA or to upgrade the IOS of the device.

It’s a new innovation from Cisco Systems which happens to the industry’s first 60-watt Power over Ethernet technology which Cisco called Universal Power over Ethernet (UPOE).

Cisco Universal Power over Ethernet (UPOE) can offer twice the power per port of products from competing switch vendors – providing both power and network access to a greater range of devices through a single standard Ethernet cable. This can surely help to lower the total cost of IT operations. By using Cisco’s new UPOE line card and UPOE splitter, any device requiring up to 60-watt power can now be powered by Cisco’s Catalyst 4500E Switches. This includes Cisco IP phones, personal telepresence systems, compact switches and Cisco wireless access points.

[kml_flashembed movie="http://www.youtube.com/v/RASdhbNdFQU" width="425" height="350" wmode="transparent" /]

Currently Cisco is working with IEEE and third-party device manufacturers to standardize UPOE in next-generation, network-enabled devices. Which for sure may lead to new PoE standard from IEEE?

Currently  Samsung zero client desktop virtualization devices and BT IP turrets have integrated Cisco UPOE technology into their devices to allow customers the immediate advantage of using their existing Cisco network to power these solutions. This is good sign for this emerging technology. Cisco also tested many devices using UPOE technology like Oracle Sun ray clients.

Currently the Cisco Universal Power over Ethernet is available with a new line card on the Cisco Catalyst 4500E switch. The Single Cisco Catalyst Switch 4500E chassis can support up to 120 UPOE ports. The OPOE is utilizes the existing UTP Cabling standard Cat 5e or higher and RJ 45 connectors for deployment. This helps the customers to make use of their existing cabling infrastructure.

Look at its popularity it was a right move by Cisco Systems to introduce the Cisco CCT Telepresence Certification, which focuses on the on the skills required for onsite support and maintenance of Cisco TelePresence Systems. Technicians in this area must be able to identify Cisco TelePresence models, accessories, cabling, and interfaces; understand the Cisco TelePresence operating modes and identify commonly found software; and be able to use the Cisco Command Line Interface (CLI) to connect and service products and make basic Cisco TelePresence system adjustments.

The only prerequisite for Cisco CCT Telepresence Certification is Cisco CCT Routing and Switching.

For further details do check the Cisco Learning Network Website

Personally I welcome the introduction of Cisco CCT Data Center certification, especially after Cisco announced their Nexus 7000, Nexus 5000, and Nexus 2000 Series Switches which are specially designed for Data Centers. Certainly this move by Cisco System empowers the Data Center operators or Technicians to demonstrate the knowledge and ability required for the onsite support and Maintenance of Cisco Data Center Products.

The Cisco CCT Data Center Certification ensures that the certified individual have knowledge of the Cisco Nexus 7000, Nexus 5000, Nexus 2000 and MSD 9000 (SAN Switches) product line along with the basic knowledge of the NX-OS and simple commands required to perform tasks such as password recovery.

In order to be  Cisco CCT Data Center Certified the only prerequisite is to have valid Cisco CCT Routing and Switching Certification.

For further details do check the Cisco Learning Network Website

Currently Cisco Systems are offering three Cisco Certified Technician (CCT) Certifications.

1)      Cisco CCT Routing & Switching certification

2)      Cisco CCT Data Center certification

3)      Cisco CCT TelePresence certification.

The Cisco CCT Routing & Switching certification which certifies that an onsite technician has the required skills and knowledge to work with Cisco Routers and Switches performing task such as troubleshooting, repairs, hot-swap of specific components, and create TAC tickets as required. The Cisco CCT Routing and Switching certification serves as a prerequisite for the Cisco CCT Data Center certification and the Cisco CCT TelePresence certification.

Exams & Recommended Training for Cisco CCT Routing & Switching certification are as follows

In my next post I will talk about Cisco CCT Data Center certification and the Cisco CCT TelePresence certification. It’s a good move from Cisco and for sure this certification is very handy and provides a solid foundation to all those technicians who are aim the sky (CCIE)

In my previous post I was talking about the problem we were facing with connectivity between Cisco 6500 Series switch and Cisco Nexus 7010 Switch. While troubleshooting we figured out there were no issues either with configuration of physical media (Fiber optic cable), the problem turned out to with 10GBASE X2 modules. Though the distance between these two locations is hardly 250 meters and there was a multimode fiber optic cable (supports 10G) running between these two locations. Initially a Cisco X2-10 GB-LX4 module was installed at Cisco 6500 Series Switch and at the Nexus 7010 we had a SFP SR Module.

Table 1. X2 Port Cabling Specifications

Intially everything looked good but after three months the problems aroused and the link start disconnecting, with the following errors

2011 Jun 12 09:05:03 VDC-Admin-CO01-MB-1256-001 %ETHPORT-5-IF_UP: Interface Ethernet1/17 is up in Layer3

2011 Jun 12 09:05:04 VDC-Admin-CO01-MB-1256-001 %ETHPORT-5-IF_DOWN_LINK_FAILURE: Interface Ethernet1/17 is down (Link failure)

2011 Jun 12 09:05:49 VDC-Admin-CO01-MB-1256-001 %ETHPORT-5-SPEED: Interface Ethernet1/17, operational speed changed to 10 Gbps

We figured out the multimode fiber optic cable used is of 62.5/125 microns. As per the Cisco X2 port cabling specifications we were supposed to use either Cisco X2-10GB-SR or Cisco X2-10GB-LX4 module at Cisco 6500 Series Switch and a SFP SR Module at Nexus 7010 Switch.

Seems like the problem occurred with the wavelength of fiber, once we replaced the Cisco X2-10GB-LX4 module with the Cisco X2-10GB-SR Module the problem was solved.

Upon looking at the log in Nexus 7010 Core Switch we found the following entries.

2011 Jun 12 09:05:03 VDC-Admin-CO01-MB-1256-001 %ETHPORT-5-IF_UP: Interface Ethernet1/17 is up in Layer3

2011 Jun 12 09:05:04 VDC-Admin-CO01-MB-1256-001 %ETHPORT-5-IF_DOWN_LINK_FAILURE: Interface Ethernet1/17 is down (Link failure)

2011 Jun 12 09:05:49 VDC-Admin-CO01-MB-1256-001 %ETHPORT-5-SPEED: Interface Ethernet1/17, operational speed changed to 10 Gbps

2011 Jun 12 09:05:49 VDC-Admin-CO01-MB-1256-001 %ETHPORT-5-IF_DUPLEX: Interface Ethernet1/17, operational duplex mode changed to Full

2011 Jun 12 09:05:49 VDC-Admin-CO01-MB-1256-001 %ETHPORT-5-IF_RX_FLOW_CONTROL: Interface Ethernet1/17, operational Receive Flow Contol state changed to off

2011 Jun 12 09:05:49 VDC-Admin-CO01-MB-1256-001 %ETHPORT-5-IF_TX_FLOW_CONTROL: Interface Ethernet1/17, operational Transmit Flow Contol state changed to off

2011 Jun 12 09:05:49 VDC-Admin-CO01-MB-1256-001 %ETHPORT-5-IF_UP: Interface Ethernet1/17 is up in Layer3

2011 Jun 12 09:05:49 VDC-Admin-CO01-MB-1256-001 %ETHPORT-5-IF_DOWN_LINK_FAILURE: Interface Ethernet1/17 is down (Link failure)

2011 Jun 12 09:07:37 VDC-Admin-CO01-MB-1256-001 %ETHPORT-5-SPEED: Interface Ethernet1/17, operational speed changed to 10 Gbps

2011 Jun 12 09:07:37 VDC-Admin-CO01-MB-1256-001 %ETHPORT-5-IF_DUPLEX: Interface Ethernet1/17, operational duplex mode changed to Full

2011 Jun 12 09:07:37 VDC-Admin-CO01-MB-1256-001 %ETHPORT-5-IF_RX_FLOW_CONTROL: Interface Ethernet1/17, operational Receive Flow Contol state changed to off

2011 Jun 12 09:07:37 VDC-Admin-CO01-MB-1256-001 %ETHPORT-5-IF_TX_FLOW_CONTROL: Interface Ethernet1/17, operational Transmit Flow Contol state changed to off

2011 Jun 12 09:07:37 VDC-Admin-CO01-MB-1256-001 %ETHPORT-5-IF_UP: Interface Ethernet1/17 is up in Layer3

2011 Jun 12 09:07:38 VDC-Admin-CO01-MB-1256-001 %ETHPORT-5-IF_DOWN_LINK_FAILURE: Interface Ethernet1/17 is down (Link failure)

2011 Jun 12 09:16:40 VDC-Admin-CO01-MB-1256-001 %ETHPORT-5-IF_HARDWARE: Interface Ethernet1/17, hardware type changed to No-Transceiver

2011 Jun 12 09:16:54 VDC-Admin-CO01-MB-1256-001 %ETHPORT-5-IF_HARDWARE: Interface Ethernet1/17, hardware type changed to 10G

2011 Jun 12 09:17:00 VDC-Admin-CO01-MB-1256-001 %ETHPORT-5-SPEED: Interface Ethernet1/17, operational speed changed to 10 Gbps

2011 Jun 12 09:17:00 VDC-Admin-CO01-MB-1256-001 %ETHPORT-5-IF_DUPLEX: Interface Ethernet1/17, operational duplex mode changed to Full

2011 Jun 12 09:17:00 VDC-Admin-CO01-MB-1256-001 %ETHPORT-5-IF_RX_FLOW_CONTROL: Interface Ethernet1/17, operational Receive Flow Contol state changed to off

2011 Jun 12 09:17:00 VDC-Admin-CO01-MB-1256-001 %ETHPORT-5-IF_TX_FLOW_CONTROL: Interface Ethernet1/17, operational Transmit Flow Contol state changed to off.

We tried to reset the Ethernet Interface in the Nexus 7010 Switch by using Cisco IOS command “shutdown” and “no shutdown”  but it’s of no use. The only way to solve this problem is to manually remove and reconnect the fiber patch cord connected to the Ethernet port in the Nexus 7010 Switch. Currently we are looking for the solution, the moment we find I will update you. Meanwhile if any solutions available make use of comments to help me.

There is a way to reduce the overhead involved in modifying ACL by using the Cisco IOS feature of resequencing.

In the following example in a Cisco router there is an access-list name ITKE

ASW2-02#sho access-lists ITKE

Extended IP access list ITKE

1 permit ip host 192.168.1.1 host 10.1.0.1

2 permit ip host 192.168.1.2 host 10.1.0.2

ASW2-02#

From the example if we need to add one more deny statement for the host 192.168.1, it’s not possible to add a statement without deleting the current access list and create a new one. But the power of resequence allows you to assign a new set of sequence numbers to current access list as demonstrated below using the IOS command “ip access-list resequence”

ASW2-02#configure t

ASW2-02(config)#ip access-list resequence ITKE ?

<1-2147483647>  Starting Sequence Number

ASW2-02(config)#ip access-list resequence ITKE 10 10

This starts the first entry with a sequence number of 10 and increments all new lines by 10. The result is as shown below

ASW2-02#sho ip access-lists ITKE

Extended IP access list ITKE

10 permit ip host 192.168.1.1 host 10.1.0.1

20 permit ip host 192.168.1.2 host 10.1.0.2

ASW2-02#

By resequencing the ACL now it’s easy to inserts a new ACL with a sequence number of 15 which would fall between the existing entries in the ITKE access list.

 The Cisco IOS IP Service Level Agreement better known as IPSLA is a feature which was introduced in the IOS version 11.2 under the name of Response Time Responder (RTR). Later on Cisco sensed RTR is creating some sort of confusion as some of reference texts referred RTR as Real time responder; hence they renamed RTR as Service Assurance Agent (SAA). Even SAA didn’t stick for long time and now it’s known as IP SLA.  IP SLA is truly excellent for built-in network testing. In fact, it is a key ingredient for sophisticated implementations of Performance Routing (PfR).

 At its introduction in IOS 11.2 version under the name of RTR it had very limited offerings  

• ICMP Ping
• ICMP Echo Path
• IBM SNANativeEcho

The Cisco IOS IP Service Level Agreement (IP SLA) feature can be used to gather realistic information about how specific types of traffic are being handled end-to-end across a network. To do this, an IP SLA device runs a preconfigured test and generates traffic that is destined for a far end device. As the far end responds with packets that are received back at the source, IP SLA gathers data about what happened along the way.

IP SLA is capable of running following tests in Cisco Switches and routers

When we are configuring Cisco Switches and Cisco routers, sometimes we need to set the interface to default settings. Using the “default interface” configuration command we can achieve the result. This command is very handy and can be used on any Cisco Router or a Cisco Switch.

In the following example I want the default configuration for the interface fast Ethernet 0/10 in the Cisco Catalyst 3500 Series Switch. By using the “default interface fast Ethernet 0/10″ I removed all the configuration of the interface

Very useful command especially when we need to remove the complete configuration of the interface only.