Hi All, I'm working on a task to add the new modules in Nexus 7K. As far I know initially all physical interfaces belong to the default VDC (VDC 1). we no need to allocate the physical interfaces to default VDC for enabling the interfaces to make configuration.   1- Do we need to allocate the physical interfaces to default VDC to enable the interfaces for configuration?   configuration: vdc id 1 allocate interface Ethernet5/1-48   thanks in advance for your help.         Regards, Thiyagu ... View more

Hello All, I was working on a task to add a new link to the existing link running between Switch B,C and D. There was a an outage of 2 to 3 minutes for all the servers connecting behind the FW which in turn is connecting to the Nexus 5K. While troubleshooting found the Firewall connected switch port went to blocking state during the RSTP re-convergence. log: %STP-6-PORT_RANGE_STATE: new_state=blocking interface=port-channel22 As per my understanding the Switch Ports will go into a blocking state at the time of election process, when a switch receives a BPDU on a port that indicates a better path to the Root Switch Please correct me if I'm wrong with my RSTP understanding? On the configuration perspective to find a solution: The switch port is configured as " switchport mode trunk" . In order to stop receiving the BPDUs we have to configure the command "spanning-tree port type trunk" Would you please help me to know configuring the switch port as "spanning-tree port type trunk" will avoid the switch port to trasistion to blocking state during the next RSTP reconvergence? Will there by any impact to the host when I change the switch port configuration to "spanning-tree port type trunk" from "switchport mode trunk" thanks in advance for your help. Regards, Thiyagu ... View more

Hello All, I'm trying to find the QoS dscp value of the source and destination using the sh ip cache flow output.   Could you please help me to find the DSCP value used by the source/destination from sh ip cache flow output?   Is there any command which will help me to find the DSCP value used by the source/destination?   Regards, Thiyagu ... View more

Hi Team, I'm seeing the below error in Nexus 5K environment. We do not have VPC configured for that interface and when I check the VPC status and I'm seeing "consistency check not performed" message.   I have tried shutting down and unshut the interface and I'm still seeing the interface in the VPC brief output with the same error message.   # sh vpc brief 102423 Eth101/1/24 down*  Not         Consistency Check Not      -                                          Applicable   Performed   sh run int Ethernet101/1/24 interface Ethernet101/1/24   switchport access vlan 9   spanning-tree port type edge   no snmp trap link-status Can you please help me to get away from the status message "Consistency check not formed" or interface status is down? Do I need to reset the interface to fix this issue?   Regards, Thiyagu     ... View more

Hello All, I'm trying to understand the functionality of fabric path and VPC in datacenter Networking. Could you please help me to know the following:   1- What is the difference between fabric path and VPC? 2- What are all the benefits we will get if we enable fabric path insted of VPC? 3- If we want to migrate from fabric path to VPC what are all the challenges we have to address? 4- Do we need a VPC domain and VLANs though we have fabricpath at aggregation layer? 5- Can fabric path load balance the traffic over the uplinks?   Thanks a lot in advance for your reply.   Regards, Thiyagu     ... View more

Hello Guys, I have been working on IP V6 and I'm trying to understand how to use IP V6 for an enterprise Network.   I have used the IP address FD20:8b1E:B255:C003::22/126   How many subnets and address available for the above IP V6?   Could you please help me to know the math to calculate subnets and avaialble address in IP V6?   Thanks a lot in advance.   Regards, Thiyagu ... View more

Hello All, Can anybody help me to know is it possible to use IP SLA for dynamic failure if a specific route is not received from specific neighbor. For example, In a dual homed scenario , if a router is not receiving route for 0.0.0.0 from ISP A and it should failover to ISP B.   Regards, Thiyagu ... View more

Hello All, I'm working in a BGP prefix list configuration and i'm seeing a strange issue.   Issue: As per the cofiguration we have defined the prefix list to filter the incomming subnets. Though a specific subnet is not allowed in the prefix list but the router is allowing the subnet to get in to BGP table from the neighbour.   configuration: ip prefix-list TEST seq 5 permit 10.61.64.0/19 ge 24 le 24   Though the below subnet is not allowed in prefix list but I'm seeing this subnet in BGP table with best path.   10.61.192.0/23   Can you anybody help me to know what could be the issue? any bug? any thing I'm wrong with the configuration?   Thanks, Thiyagu ... View more

Hello All, We are troubleshooting a performance issue in our Network. UDP traffic from a particular application is completely congesting the link. Though we have QoS to throttle the traffic from the application to use only 9% bandwith of the link but that application flodding the traffic around 80% of the link. The traffic from the application is getting categorised as default traffic CS0.   Class class-default       fair-queue       bandwidth remaining 9 (%)   Is there anything we are missing in the configuration of the class-map that is alowing the flodding of the UDP traffic? Regards, Thiyagu             ... View more