iSCSI Boot with VMware ESXi on Cisco UCS

This is a follow up post to the iSCSI Boot From SAN post that shows how the virtual networking and Storage Adapter configuration of ESXi looks post install.


Note:  At the time that I posted this, only ESXi 4 is supported by Cisco for iSCSI Boot From SAN on Cisco UCS but ESXi 5 is what I had on hand to test the iSCSI Boot From SAN configuration.


  Once the networking configuration for the host has been completed, connect to the host with the vSphere Client.  The first iSCSI enabled vNIC for the Service Profile is automatically added to a vSwitch and a vmkernel port is configured with the IP address that was configured in the Boot Parameters for the 1^st iSCSI vNIC in the server’s Service Profile referenced from my post here.

iSCSI Boot from SAN on Cisco UCS

Last week Cisco released the new 2.0 code for Cisco UCS.  I had some time to play with the update and tried out the new iSCSI Boot from SAN support feature to see how it works.  Here are some of the steps I used to get a VMware ESXi 5.0 host up and running via iSCSI storage on UCS.

Service Profile and vNIC Configuration

1)      In the UCSM, create a Service Profile.  This profile will be created as usual(except for vHBAs) but make sure that you create 2 vNICs that will be reserved for iSCSI traffic.  UCS will use these vNICs as “Overlay NICs” that will provide the VLAN connectivity details for the iSCSI vNICs in the Service Profile.

2)      Configure the VLANs on the Overlay vNICs by selecting the vNIC and clicking the Modify VLANs link in the working pane. 

3)      In the Modify VLANs window, Select your VLAN for iSCSI and select the “Native VLAN” radial button for the VLAN.  Making this the native VLAN for the Overlay vNICs will pass the frames for the iSCSI VLAN untagged and ease the configuration and installation of the OS.  Click OK, and then click the Save Changes button in the working pane for the vNIC.  Repeat these steps for the 2^nd vNIC that will be used as an Overlay vNIC for iSCSI.

Activating UCS System and Fabric Interconnect Firmware from CLI

Activating UCS System and Fabric Interconnect Firmware from CLI

I recently had to update the firmware on 2 UCS 6120XPs FIs that were on different firmware versions at the UCS Manager(USCM, also called system) level of the interconnects.  

My first step was to erase the configs on each interconnect and setup was rerun to configure the FIs in "stand-alone" mode.  Also the firmware packages were already loaded to the servers via the GUI(Please refer to the CLI documentation for steps on erasing the configuration and uploading firmware images).  To update the firmware via the CLI I used the following steps:

Direct Attached FC Storage with UCS

Cisco has released the new code release (1.4.1j). I had the chance of setting up one of the newest features included in this code release which is configuring direct attached storage from an EMC storage array directly to UCS 6120XP fabric interconnects. The process was not that difficult but there were some configurations that had to be played with to make this work properly for Boot from SAN connectivity that I have not dealt with for previous configurations with Storage connected via a fabric switch. Here are the steps we used to make this work:

UCS configuration:

1. Connect the FC storage to the FC expansion modules on the UCS 6120xp
2. In the UCS Manager, select a interconnect and in the general tab in the right pane select “Set FC Switching Mode”. Note: This will cause the Fabric Interconnects to reboot.
3. Once the UCS Manager is back online, select one of the Fabric Interconnects, then on the General tab in the right window, right click the desired FC ports of FC Expansion module and select “Configure as FC Storage Port” in the drop down
4. On the default VSAN, select “Enable Default Zoning. This allows the 6100 to communicate with the storage and vice versa for sharing the WWPN of devices.
5. Next, configure the boot policy for the host.