UCS C-Series ESXi Install

Installing ESXi on a Cisco UCS C-Series is pretty much as straightforward as you can get. Pretty similar to any standard data center server out on the market today. But with a USB install, no supported software RAID and no optical drive there can be a few ‘gotchas’ getting everything set up permanently. This step by step install should get you up an running quickly on an external mounted USB drive. This guide also applies to installs on the Cisco Flexible Flash Card.

Cisco Integrated Management Console

Cisco UCS C-Series servers are standalone rack-mounted servers. These servers can be incorporated into management with Cisco Fabric Interconnects but require special planning. Fortunately like many datacenter ready servers, Cisco UCS C-Series servers include their own out-of-band management called CIMC or Cisco Integrated Management Console. CIMC is similar to HP’s iLO and IBM’s IMM. These features allow an administrator to manage a server through the network by remote control regardless if the server is on or if it has an OS. Similar to a directly connected KVM.

The CIMC gives you the ability to see the servers status as well as controls its server state. It also allows you to attach media such as an ISO directly to the machine via a virtual CD/DVD or even a floppy disk. Because of this feature most Cisco UCS C-Series servers do not come with an optical drive. Without an optical drive we must first launch and configure CIMC to install our ESXi hypervisor. Lets go!

(click images for full size – settings are highlighted in yellow)

1.  After first booting the UCS server you will receive a status screen. Press key F8 on your keyboard to tell the server to enter CIMC. The server will continue to initilize and run checks. The screen may change but the server will eventually enter the CIMC Configuration Utility


2.  Depending on server build and NIC setup, you will receive different options in this menu. Fill in the IP information for your CIMC access. If you plan on only using one NIC for CIMC management then you will need to make changes to two areas in order to achieve connectivity:

  1. Change NIC redundancy to: None
  2. Change NIC mode to: Dedicated

This allows the physical management port to be used solo and the other NIC’s to be used for ESXi purposes. Note: this does lose redundancy to the CIMC. Use F10 to save the configuration and then ESX to exit and continue booting the CIMC


3.  Slight pause before we continue on. If you need to change these settings in the future, you don’t need to reboot your server. You can access the CIMC Admin > Network Settings to change the settings in the step above.


4.  Once you have exited CIMC keep an eye out duirng the boot process – you may see raid and arrays spinning up. If you have not yet configured your RAID settings, hit CTRL + H during this process. This will enter the WebBIOS configuration tool.


5.  Select RAID Adapter – may be multiple choices depending on  how ordered


6.  You should now be at the WebBIOS selection menu. You will notice groups of ‘virtual drives’ and ‘physical drives’ Most likely you will not show any virtual drives because you have not yet setup your RAID array. Click on Configuration Wizard to continue


7.  The next few screens will take us through a configuration wizard. The wizard will allow you control over how to create your RAID You can clear out any existing configurations made earlier or if you haven’t



8.  Selected yes, cause you’re ready!


9.  If have special RAID or disk requirements you can choose manual configuration to provision that now. I choose Automatic and Redundancy as our UCS C-Series are ordered for local disks to operate at RAID 6 for all drives. This may vary depending on what purpose you are using local storage. If this is your local storage for Guest Operating Systems, you will probably want to choose the most redundant RAID setup to ensure your VM’s are available in case of a hard disk failure. You can check the difference in suggesting in automatic setup by selecting back and changing the options.


10.  Here, in automatic configuration, this is the suggested configuration. Perfect, RAID 6 with over 1.6 TB in local storage. You can always select back to change settings to see what is recommended. 


11. Just your standard warning confirmation screen.


12.  After completing RAID setup, shutdown the server. Make sure your install medium is inserted before powering up. Cisco Flex Flash installs inside the server. There is also a internal USB slot in the server but I have never been able to get it to work correctly. After POST select F6 for the boot menu. Here you may need to select your install medium – either Cisco Flex Flash or a USB stick in one of the empty USB slots.


13.  Now we return to CIMC via the network (dont select CIMC Config from boot menu. Click the Server tab. Click on Launch KVM Console or they keyboard icon. KVM will launch showing you the UCS. Click on the VM tab.

  1. Click on Add Image button
  2. Locate the ESXi ISO you want to install
  3. Select the Mapped checkbox


14.  You may need to restart the server if it has stalled looking for media. Once ready, ESXi will load and then prompt you to install to a location you select.


15.  After install, you may now access your ESXi host via the vSphere Client. Select Configuration tab and then the Storage link under Hardware group. Finally click the add


16.  When the add storage window appears click Disk/LUN. Next.


17.  Select the local disk group we set up earlier (depending on your disk arrangement you may have multiple groups here).


18.  Just a quick review here. Important thing to notice is that ESXi knows this disk is blank. Good sanity check there!


19.  Enter the name for your datastore – localdisk/lun one/iso storage etc.


20.  And done! You should see you UCS C-Series local storage available. Browse the datastore, upload some ISO’s and get to building!