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User EXEC  Denoted by “ > ” or Router > User EXEC commands allow you to connect to remote devices, change terminal settings on a temporary basis, perform basic tests, and list system information. The EXEC commands available at the user level are a subset of those available at the privileged level. Privileged EXEC Denoted by “ # ” or Router # Privileged EXEC commands set operating parameters. The privileged command set includes those commands contained in user EXEC mode, and also the  configure  command through which you can access the remaining command modes. Privileged EXEC mode also includes high-level testing commands, such as  debug . Global configuration Denoted by “ Config ” or Router (Config)# Global configuration commands apply to features that affect the system as a whole. Interface configuration  Denoted by “ (Config-if) ” or Router (Config-if)# Interface configuration commands modify the operation of an interface such as an Ethernet or ser

How to configure fencing on RedHat or CentOS Linux installed on Cisco Unified Computing System UCS blade Servers. Below is a single command to shut a blade server when configuring fencing on Linux Command to enter on redhat machine #fence_cisco_ucs -a UCS-Domain-VIP -l User-ID -p ******** -z -n org-root/SERVICE-PROFILE-NAME -o status replace above in blue font with the following information UCS-Domain-VIP                 =              UCS manager IP User-ID                                   =              User ID ******                                       =              password of User ID SERVICE-PROFILE-NAME =              replace it with the service profile name of the server Create a new ID in UCS Manager with only power on/off rights, and use that ID to send fencing poweroff command to the UCS Blades from RedHat Linux

After configuring UCS Service profile, installing VMWare ESXi and configuring Nexus 1000v, i found VMWare vmnics were showing 20 gbps per nic. It was little confusing for me as each UCS Server port from blade to Fabric Interconnect should show 10 gbps. I started exploring it and found an interesting design of Cisco UCS VIC Cards 1340/1380 or UCS Port expander. As you can see there is  hardware port channel  between the virtual nics, and the outward ports connected to the IO modules.  As you can see it depends upon different type of connectivity between VIC cards and IO Modules, if you are connecting VIC 1340 without port expander then hardware port-channel see only two 10 gig interfaces connected to it and it presents 20 gig connections to each server Ethernet link, vmnic on ESXi in our case. And if a port expander is connected then the hardware port-channel sees four 10 gig interfaces connected to it so it represents as 40 gig connection for each Ethernet link down the Serv

It is always very easy to install additional hardware components to Cisco UCS blade or Rack servers in non-production environment. If you have to add something to Cisco UCS blade or Rack server in your company’s data center or in customer production environments then you are given a small time window to perform your activity and resume the Server or compute infrastructure in production. In this case you have to put extra efforts and create method of procedure MOP, to avoid any delay and surprises during your Change Request CR window and complete the task before the end of the CR window. Writing this post to save your time if you are going to install additional hardware components e.g Memory RAM/DIMM, Network interface cards, NICs, or VIC, hard drives etc. You got to plan it well, otherwise you may stuck with troubleshooting and run out of time in CR window time. Before installing the new hardware components, make sure the new hardware is compatible with your blade/rack server, sup